Power Train. Chapter 5

Transcription

1 Chapter Power Train Spefications Test Spefications Repair Spefications Hydraulic Hose, Tube, and Fitting General Instructions O-Ring Installation Hydraulic Hose Installation Hydraulic Service Tools Portable In-Line Filter Digital Hydraulic Tester Hydraulic Flow Meter Digital Pressure Gauge Kit Hydraulic Hose Kit Hydraulic Test Fitting Kit Blocking Disk Set Component Location Theory of Operation and Sub-Circuit Schematics Traction Circuit Neutral Schematic and Theory of Operation Traction Circuit Neutral Schematic Traction Circuit Forward Mow Speed Schematic and Theory of Operation Traction Circuit Forward Mow Speed Schematic Traction Circuit Forward Transport Speed Schematic and Theory of Operation Traction Circuit Forward Transport Speed Schematic Traction Circuit Reverse Schematic and Theory of Operation Traction Circuit Reverse Schematic Troubleshooting Field Test Procedures Preliminary s Traction System Test Instrument Test Procedures Instrument Test Overview Traction System Test Gear Pump 1 Test Control Test Wheel Motors Test Traction Metering Test Rev A -1

2 POWER TRAIN Repair Gear Pump Traction Metering Front Wheel Motor Rev A

3 POWER TRAIN Spefications Test Spefications Spefication Gear Pump 1 Flow gpm (lpm) 8.7 (32.8) at 3400 rpm Gear Pump s 2 Flow gpm (lpm). (21.2) at 3400 rpm Traction Relief Pressure Setting psi (bar) 100 ± 10% (103 ± 10%) Left Reel Relief Pressure Setting psi (bar) 100 ± 10% (103 ± 10%) Hydraulic Leakage Percentage Ranges 0 10% = Good 11 20% = Marginal 21% and Beyond = Bad Repair Spefications Spefication Gear Pump Mounting Screw Torque lb-ft (N m) (23 28) Gear Pump Coupler Set Screw Torque lb-in. (N m) (1 18) Gear Pump Inlet Port Fitting Torque lb-ft (N m) 37 (0) Gear Pump 1 Outlet Port Fitting Torque lb-ft (N m) 2 (70) Gear Pump s 2 Outlet Port Fitting Torque lb-ft (N m) 2 (18) Gear Pump Rear Cover-to-Pump Body Retaining lb-ft (N m) 2 (70) Screw Torque Traction Metering Ports A and C Fitting lb-ft (N m) 30 (41) Torque Traction Metering Port B Fitting Torque lb-ft (N m) 3 (47) Front Wheel Motor Inlet and Outlet Fitting Torque lb-ft (N m) 30 (41) Rev A -3

4 POWER TRAIN Hydraulic Hose, Tube, and Fitting General Instructions O-Ring Installation Always install new O-rings. On hoses with O-ring fittings, make sure O-rings are properly seated before tightening. O-rings should be lubricated with the fluid to be used in the system prior to assembly. Boss Fitting O-Ring Installation 3 TN407 1 Tubing O.D. or Hose I.D. 2 O-Ring 3 Thread Size O-Ring Seal Kits SAE Boss O-Ring Kit Jacobsen PN O-Ring Face Seal (ORS) O-Ring Kit PN Common O-Ring Sizes Kit PN Replacement O-Rings for ORS (Face Seal) Fittings ORS (Face Seal) Tube Size ORS (Face Seal) O-Ring Size Jacobsen Part Number TN4097 Replacement O-Rings for O-Ring Boss Fittings Tubing O.D. or Hose I.D. Thread Size Hydraulic Hose Installation Jacobsen Part Number 1/8 / /1 3/ /4 7/ /1 1/ /8 9/ /2 3/ /8 7/ /4 1-1/ /8 1-3/ / /4 1-/ /2 1-7/ / Hold the fixed portion of the hose coupling with one wrench; use a second wrench to tighten or loosen the hose nut. This will avoid damaging the fitting seal. When tightening a hose, do not permit the hose to twist; hold the hose in a normal straight position. When installing hoses, place fittings at angles to avoid contact with fixed parts when turning. Make sure hoses are assembled to proper A and B ports on components. Hydraulic Hose and Tube Torque Values Size lb-ft N m Dash Fractional Min Max Min Max -4 1/ / / / / / / Rev A

5 POWER TRAIN Hydraulic Service Tools NOTE The hydraulic service tools listed here can be obtained from K-Line Industries at Digital Hydraulic Tester Part Number AT40031 Portable In-Line Filter Part Number JAC097 TN4288 When hydraulic components fail internally, debris from the failed component can spread throughout the hydraulic system and cause additional damage. This situation can be magnified when dealing with a closed-loop traction system, where oil is not filtered. In the event of a traction system component failure, it is recommended that all traction system components be disassembled and cleaned, or filtered using a portable in-line filter available through your Jacobsen Dealer. The portable in-line filter should also be used when testing hydraulic systems or after replang a failed component. IMPORTANT TN428 Always install the in-line filter so oil flows through the filter before entering a component. Once filtering has begun, never reverse the flow of oil, or debris will re-enter the system. Features Flow up to 100 gpm (379 lpm) Pressure up to 000 psi (414 bar) Temperature up to 20 F (120 C) Digital display for flow and temperature Analog display for pressure Flow accuracy 1% of full scale Hydraulic Flow Meter Part Number AT40002 TN4287 Features Glycerin filled pressure gauge Presion needle-type load valve 4 40 gpm (1 1 lpm) flow range Pressure up to 000 psi (34 bar) -12 port size Rev A -

6 POWER TRAIN Digital Pressure Gauge Kit Part Number JAC10 Hydraulic Test Fitting Kit Part Number JAC001A Features Quick disconnect fittings Pressure up to 000 psi (34 bar) Includes one ft (12 cm) hose Hydraulic Hose Kit Part Number JAC001H NOTE This hydraulic hose kit is intended to be used with the JAC001A Hydraulic Test Fitting Kit. Contents TN4290 Two 8 ft (244 cm) 12 ORFS (F) x 10 ORFS (F) hoses Four 8 ft (244 cm) 10 ORFS (F) x 10 ORFS (F) hoses Two 8 ft (244 cm) 8 ORFS (F) x 10 ORFS (F) hoses NOTE For detailed component descriptions and sizes, please see the K-Line Industries website at Contents Twenty ORFS tee fittings in five sizes Eight ORFS 90 elbow fittings in four sizes Forty ORFS caps in five sizes Forty ORFS plugs in five sizes Six ORS reducer adapters in three sizes Sixteen ORS adapters in four sizes Eight blocking disks in four sizes Three JIC tee fittings in three sizes Three 4 in. (102 mm) jumper hoses in three sizes One ORS/male NPTF adapter One vented bushing One copper tube assembly Blocking Disk Set Part Number JAC001-1 TN4289 NOTE This blocking disk set is part of the JAC001A Hydraulic Test Fitting Kit. Contents Two - blocking disks Two -8 blocking disks Two -10 blocking disks Two -12 blocking disks Two -1 blocking disks Rev A

7 POWER TRAIN Component Location See Figures -1 and Control 2 Load Control Figure -1: Component Location Left Side TN3242, TN333, TN Rev A -7

8 POWER TRAIN Hydraulic Oil Tank 3 Traction Metering Gear Pump 2 Right Front Wheel Motor 4 Left Front Wheel Motor Figure -2: Component Location Right Side TN Rev A

9 POWER TRAIN Page Intentionally Blank Rev A -9

10 POWER TRAIN Theory of Operation and Sub-Circuit Schematics Traction Circuit Neutral Schematic and Theory of Operation System Conditions: Engine running Park brake released Traction lever in the neutral position Oil Supply to the Traction The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 1 of the gear pump is routed to port P1 of the control valve, and operating pressure oil from section 4 of the gear pump is routed to port P2 of the control valve. Traction Neutral Circuit Operating pressure oil supplied from section 1 of the gear pump enters the control valve at port P1, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, against the check valve, through the traction valve, and exits the control valve at port A. With the traction valve in the neutral position, oil also flows across the open center of the traction valve and flows through the control valve, to the hydraulic filter, and then to the hydraulic tank. Oil exiting port A is routed to the wheel motors in parallel, through the traction metering valve, through port B of the control valve, and to the traction valve. Since pressure is equal on both sides of the wheel motors, no movement occurs. Operating pressure oil supplied from section 4 of the gear pump enters the control valve at port P2, flows against the 100 psi (103 bar) relief valve, through the left reel valve, through the traction valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank Rev A

11 POWER TRAIN Traction Circuit Neutral Schematic See Figure -3. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Relief Relief 100 psi 100 psi Left Reel Center Reel Center Reel Relief 100 psi Lower Relief 1200 psi Right Reel Lift/Lower Raise/Right Reel Relief 1700 psi A B A B A B A B A B Traction Metering Backlap Backlap Backlap Front Cylinder 0.09 in. Standard (See Note) Load Control in. P V Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Inlet or Drain Oil Figure -3 Return Oil TN Rev A -11

12 POWER TRAIN Traction Circuit Forward Mow Speed Schematic and Theory of Operation System Conditions: Engine running Park brake released Traction lever in the mow position Oil Supply to the Traction The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 1 of the gear pump is routed to port P1 of the control valve, and operating pressure oil from section 4 of the gear pump is routed to port P2 of the control valve. Traction Drive Circuit Operating pressure oil supplied from section 1 of the gear pump enters the control valve at port P1, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, against the check valve, through the traction valve, and exits the control valve at port A. Oil exiting port A is routed to the wheel motors in parallel and to the traction metering valve. The traction metering valve controls the oil flow from the fixed-displacement gear pump. With oil flow restricted at the traction metering valve, oil flows through the wheel motors, driving the motors. Return oil from the wheel motors is routed through the traction metering valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank. Operating pressure oil supplied from section 4 of the gear pump enters the control valve at port P2, flows against the 100 psi (103 bar) relief valve, through the left reel valve, through the traction valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank. Circuit Relief The forward mow speed rcuit is protected by the 100 psi (103 bar) relief valve. The relief valve will open if the pressure rises to 100 psi (103 bar), allowing oil to dump through the control valve, to the hydraulic filter, and then to the hydraulic tank Rev A

13 POWER TRAIN Traction Circuit Forward Mow Speed Schematic See Figure -4. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Raise/Right Reel Relief 1700 psi A B A B A B A B A B Traction Metering Backlap Backlap Backlap Front Cylinder 0.09 in. Standard (See Note) Load Control in. P V Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Figure -4 Inlet or Drain Oil Return Oil TN Rev A -13

14 POWER TRAIN Traction Circuit Forward Transport Speed Schematic and Theory of Operation System Conditions: Engine running Park brake released Traction lever in the transport position Oil Supply to the Traction The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 1 of the gear pump is routed to port P1 of the control valve, and operating pressure oil from section 4 of the gear pump is routed to port P2 of the control valve. Traction Drive Circuit Operating pressure oil supplied from section 1 of the gear pump enters the control valve at port P1, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, against the check valve, through the traction valve, and exits the control valve at port A. Oil exiting port A is routed to the wheel motors in parallel and to the traction metering valve. The traction metering valve controls the oil flow from the fixed-displacement gear pump. With oil flow restricted at the traction metering valve, oil flows through the wheel motors, driving the motors. Operating pressure oil supplied from section 4 of the gear pump enters the control valve at port P2, flows against the 100 psi (103 bar) relief valve, through the left reel valve, and enters the traction valve, where it joins the oil flow from section 1 of the gear pump to the wheel motors. The combined oil flow from sections 1 and 4 of the gear pump enable faster wheel speed. Return oil from the wheel motors is routed through the traction metering valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank. Circuit Relief The forward transport speed rcuit is protected by the 100 psi (103 bar) relief valve. The relief valve will open if the pressure rises to 100 psi (103 bar), allowing oil to dump through the control valve, to the hydraulic filter, and then to the hydraulic tank Rev A

15 POWER TRAIN Traction Circuit Forward Transport Speed Schematic See Figure -. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Raise/Right Reel Relief 1700 psi A B A B A B A B A B Traction Metering Backlap Backlap Backlap Front Cylinder 0.09 in. Standard (See Note) Load Control in. P V Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Figure - Inlet or Drain Oil Return Oil TN Rev A -1

16 POWER TRAIN Traction Circuit Reverse Schematic and Theory of Operation System Conditions: Engine running Park brake released Traction lever in the reverse position Oil Supply to the Traction The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 1 of the gear pump is routed to port P1 of the control valve, and operating pressure oil from section 4 of the gear pump is routed to port P2 of the control valve. Traction Drive Circuit Operating pressure oil supplied from section 1 of the gear pump enters the control valve at port P1, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, against the check valve, through the traction valve, and exits the control valve at port B. Oil exiting port B is routed through the traction metering valve to the wheel motors in parallel, driving the motors. Return oil from the wheel motors is routed against the traction metering valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank. Operating pressure oil supplied from section 4 of the gear pump enters the control valve at port P2, flows against the 100 psi (103 bar) relief valve, through the left reel valve, through the traction valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank. Circuit Relief The reverse rcuit is protected by the 100 psi (103 bar) relief valve. The relief valve will open if the pressure rises to 100 psi (103 bar), allowing oil to dump through the control valve, to the hydraulic filter, and then to the hydraulic tank Rev A

17 POWER TRAIN Traction Circuit Reverse Schematic See Figure -. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Raise/Right Reel Relief 1700 psi A B A B A B A B A B Traction Metering Backlap Backlap Backlap Front Cylinder 0.09 in. Standard (See Note) Load Control in. P V Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Figure - Inlet or Drain Oil Return Oil TN Rev A -17

18 POWER TRAIN Troubleshooting Mower Will Not Move Forward or Reverse Probable Cause Hydraulic oil not at correct level in reservoir. Front wheel motor(s) worn or damaged. Pump worn or damaged. Traction metering valve worn or damaged. Remedy Fill reservoir to correct level. (Refer to Parts and Maintenance Manual for correct oil spefications.) Test motor(s). (See Wheel Motors Test on page -2.) Repair or replace motor as needed. (See Front Wheel Motor on page -39.) Test pump. (See Traction System Test on page -21.) Repair or replace pump as needed. (See Gear Pump on page -31.) Test valve. (See Traction Metering on page -38.) Repair or replace valve as needed. (See Traction Metering on page -38.) Mower Will Not Reach Full Speed Probable Cause Hydraulic oil not at correct level in reservoir. Air in hydraulic system (air bubbles in hydraulic oil). Pump worn or damaged. Front wheel motor(s) worn or damaged. Engine RPM low. Traction metering valve not fully stroked. Hydraulic System Operating Hot Remedy Fill reservoir to correct level. (Refer to Parts and Maintenance Manual for correct oil spefications.) suction line for air leaks. Repair as needed. Operate various hydraulic systems until hydraulic system is free of air. Test pump. (See Traction System Test on page -21.) Repair or replace pump as needed. (See Gear Pump on page -31.) Test motor. (See Wheel Motors Test on page -2.) Repair or replace motor as needed. (See Front Wheel Motor on page -39.) Verify and adjust engine RPM. (Refer to engine manufacturer s manual for further instructions.) Adjust traction pedal. (See Traction Pedal Adjustment on page 9-.) Probable Cause Hydraulic oil not at correct level in reservoir. Slippage in pump or motor. Excessive Pump Noise Remedy Fill reservoir to correct level. (Refer to Parts and Maintenance Manual for correct oil spefications.) Perform instrument tests. (See Instrument Test Overview on page -20.) Probable Cause Hydraulic oil not at correct level in reservoir. Hydraulic oil cold. Air in hydraulic system (air bubbles in hydraulic oil). Pump worn or damaged. Remedy Fill reservoir to correct level. (Refer to Parts and Maintenance Manual for correct oil spefications.) Warm hydraulic oil to operating temperature. suction line for air leaks. Repair as needed. Operate various hydraulic systems until hydraulic system is free of air. Test pump. (See Traction System Test on page -21.) Repair or replace pump as needed. (See Gear Pump on page -31.) Rev A

19 POWER TRAIN Field Test Procedures When a hydraulic system failure occurs, some simple effective tests can be performed prior to using a test instrument. The results of these tests can lead you to the suspected component failure. More extensive test procedures, using test instruments, are presented later in this section. (See Instrument Test Procedures on page -20.) Preliminary s Perform the following checks prior to beginning any tests. 1. the hydraulic oil reservoir for proper fluid level, the presence of air or water, and unusual odor. 2. all hoses, tubes, and fittings for leaks. Tighten as needed. 3. Eliminate all mechanical issues prior to starting hydraulic tests. 3. Release park brake, lower the cutting units, move throttle lever to full throttle, and move traction lever to the mow position. Slowly push the traction pedal forward. Does the engine labor or stall? YES The gear pump is not faulty. NO A fault exists in the traction rcuit, which includes the gear pump, control valve, and wheel motors. Proceed to instrument test. (See Instrument Test Procedures on page -20.) Traction System Test See Figure Operate hydraulic system until oil temperature is at F (49 C). 1 Figure Install wheel restraints (1) to both front wheels. TN Rev A -19

20 POWER TRAIN Instrument Test Procedures Instrument Test Overview The following tests are spefically designed to approach hydraulic testing on a system level. Each component within the system represents a portion of the total system leakage. An internal leakage percentage for each component will be calculated and recorded, enabling the technian to view the system performance issue more completely. The test results will help the technian to dede which repairs will best remedy the performance issue experienced by the operator. The internal leakage percentage ranges are as follows: 0 10% = Good 11 20% = Marginal 21% and Beyond = Bad Example: Traction System Performance Complaint The machine operator reports that the machine struggles to climb hills. The traction system is tested as outlined, and the calculated system leakage is 31%, a result that requires the testing of individual components. This result can also be interpreted as system effiency of 9%. The components in question are as follows: gear pump section 1, control valve section, left wheel motor, and right wheel motor. Following the procedures as outlined, test each individual component, then calculate and record leakage percentages. The results from this test reveal leakage of % in gear pump section 1, 20% in control valve section,.3% in the left wheel motor, 2.8% in the right wheel motor, and 1.4% in the traction metering valve. Although all the components lend to the overall system leakage, only control valve section, which is at the extreme end of the marginal range, would be considered for repair or replacement. Formulas: System and Gear Pump No Load Flow Loaded Flow / No Load Flow x 100 = Leak Percentage Control and Wheel Motors Loaded Flow from previous component Loaded Flow from current component / Loaded Flow from previous component x 100 = Leak Percentage Calculations: Traction System Test No Load Flow = 10 gpm Loaded Flow =.9 gpm 10.9 / 10 x 100 = Total Traction System Leakage 31% Gear Pump 1 Test No Load Flow = 10 gpm Loaded Flow = 9. gpm / 10 x 100 = Gear Pump 1 Leakage % Control Test Loaded Flow from gear pump section 1 test = 9. gpm Loaded Flow from control valve section test = 7. gpm / 9. x 100 = Control Leakage = 20% Left Wheel Motor Test Loaded Flow from control valve section test = 7. gpm Loaded Flow from left wheel motor test = 7.2 gpm / 7. x 100 = Left Wheel Motor Leakage =.3% Right Wheel Motor Test Loaded Flow from control valve section test = 7.2 gpm Loaded Flow from right wheel motor test = 7.0 gpm / 7.2 x 100 = Right Wheel Motor Leakage = 2.8% Traction Metering Test Loaded Flow from control valve section test = 7.2 gpm Loaded Flow from traction metering valve test = 7.1 gpm / 7.2 x 100 = Traction Metering Leakage = 1.4% Rev A

21 POWER TRAIN Traction System Test See Figures -8 through -11. IMPORTANT This test works together with the Gear Pump 1 Test, Control Test, Wheel Motors Test, and Traction Metering Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Wheel Restraints Figure Install tee fitting () to fitting (1). 4. Connect test hose () of flow meter inlet and hose (2) to tee fitting (). NOTE Make sure hose end is under oil level in hydraulic tank to prevent aeration of oil.. Secure flow meter outlet hose (3) to the hydraulic tank fillneck. 3 4 TN Park the mower safely. (See Park Mower Safely on page 1-.) Figure Disconnect hose (2) from fitting (1). TN3393 TN171 Figure -10. Install wheel restraints (7) to both front wheels. 7. Open flow meter valve (4) completely Rev A -21

22 POWER TRAIN Figure -11: Traction System Test Front Wheel Motors Restrained 8. Bypass seat switch. 9. Ensure park brake is engaged. NOTE TN349 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 10. Start engine and run at full throttle (3400 rpm ± 0). 11. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (4) until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 12. Move traction lever to the mow position. 13. Fully engage the traction pedal. 14. Read and record no load flow. 1. Slowly close flow meter valve (4) until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record loaded flow. 1. Open flow meter valve, release traction pedal, return traction lever to the neutral position, and stop engine. 17. Calculate traction system leakage. (Step 14 Step 1 / Step 14 x 100 = Leak Percentage) Is traction system leakage 10% or less? YES Traction system is good. Proceed to step 18. NO Proceed to next question. Is traction system leakage 11% to 20%? YES Traction system is marginal. Additional testing is required. Proceed to Gear Pump 1 Test on page -23. NO Proceed to next question. Is traction system leakage 21% or more? YES Test individual components in traction system for leakage. Proceed to Gear Pump 1 Test on page Remove wheel restraints from front wheels. 19. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 20. Install and connect all components as noted prior to test. 21. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 22. Start engine. hydraulic system for leaks. Repair as necessary Rev A

23 POWER TRAIN Gear Pump 1 Test See Figures -12 through -14. IMPORTANT This test works together with the Traction System Test, Control Test, Wheel Motors Test, and Traction Metering Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Figure Disconnect hydraulic hose (1) from tee fitting (3). Plug hydraulic hose (1) and cap tee fitting (3). 4. Open flow meter valve (2) completely. 3 2 TN133 Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Traction System Test on page -21, leaving flow meter connected as outlined. 1 TN3470 Figure -14: Gear Pump 1 Test Cap and Plug Between Gear Pump 1 and Control Figure -12 TN3393. Bypass seat switch.. Ensure park brake is engaged. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0) Rev A -23

24 POWER TRAIN! CAUTION Do not exceed 100 psi (103 bar) as this test does not utilize system relief, and damage may occur to hydraulic system components. 8. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record gear pump section 1 loaded flow. 10. Open flow meter valve and stop engine. 11. Calculate gear pump section 1 leakage. (Step 14 of previous test Step 9 / Step 14 of previous test x 100 = Leak Percentage) Is gear pump section 1 leakage 10% or less? YES Gear pump section 1 is good. Proceed to step 12. NO Proceed to next question. Is gear pump section 1 leakage 11% to 20%? YES Gear pump section 1 is marginal. Additional testing is required. Proceed to step 12. NO Proceed to next question. Is gear pump section 1 leakage 21% or more? YES Repair or replace gear pump section 1. See Gear Pump on page -31, then proceed to step 12. NO Proceed to step (See Figure -12.) Remove cap and plug and reconnect hydraulic hose (1) to tee fitting (3). 13. Proceed to Control Test on page -24. Control Test See Figures -1 through -17. IMPORTANT This test works together with the Traction System Test, Gear Pump 1 Test, Wheel Motors Test, and Traction Metering Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Flow Meter Tee Fitting Cap Plug Required Tools and Materials 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Traction System Test on page -21, leaving flow meter connected as outlined. 1 2 TN347 Figure Disconnect tube (1) from tee fitting (2). Plug hydraulic tube (1) and cap tee fitting (2) Rev A

25 POWER TRAIN! CAUTION Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. Figure Open flow meter valve (3) completely. 3 TN Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (3) until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record control valve section loaded flow. 11. Open flow meter valve, release traction pedal, return traction lever to neutral position, and stop engine. 12. Calculate control valve section leakage. (Step 9 of previous test Step 10 / Step 9 of previous test x 100 = Leak Percentage) Is control valve section leakage 10% or less? YES Control valve section is good. Proceed to step 13. NO Proceed to next question. Is control valve section leakage 11% to 20%? YES Control valve section is marginal. Additional testing is required. Proceed to step 13. NO Proceed to next question. Is control valve section leakage 21% or more? YES Repair or replace control valve section. See Control on page -9, then proceed to step 13. Figure -17: Control Test Cap and Plug at Wheel Motors. Bypass seat switch.. Ensure park brake is engaged. NOTE TN3471 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0). 8. Move traction lever to the mow position and fully engage the traction pedal.! CAUTION Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. 13. Open flow meter valve completely before starting engine. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 14. Start engine and run at full throttle (3400 rpm ± 0). 1. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached Rev A -2

26 POWER TRAIN 1. Move traction lever to the mow position. 17. Continue to close flow meter valve until zero flow is obtained, and record traction relief valve pressure. Is traction relief pressure 100 ± 10% psi (103 ± 10% bar)? YES Traction relief valve is good. Open flow meter valve, return traction lever to the neutral position, and stop engine. Proceed to step 19. NO Proceed to step Adjust traction relief valve by adding or removing shims as necessary. (See Disassembly, Inspection, and Assembly on page -8.) Close flow meter valve until zero flow is obtained, and record traction relief valve pressure. Can traction relief valve be adjusted to relieve at 100 ± 10% psi (103 ± 10% bar)? YES Traction relief valve is good. Open flow meter valve, return traction lever to the neutral position, and stop engine. Proceed to step 19. NO Replace traction relief valve. See Control on page -9, then proceed to step (See Figure -1.) Remove cap and plug and reconnect hydraulic tube (1) to tee fitting (2). 20. Proceed to Wheel Motors Test on page -2. Wheel Motors Test See Figures -18 through -24. IMPORTANT This test works together with the Traction System Test, Gear Pump 1 Test, Control Test, and Traction Metering Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Caps Plugs Wheel Restraints 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Control Test on page -24, leaving flow meter connected as outlined. 1 Figure Install wheel restraints (1) to both front wheels. TN Rev A

27 POWER TRAIN Left Wheel Motor Test 2 3 Figure -21 TN133 Figure -19 TN Open flow meter valve () completely. 4. Disconnect tube (3) from fitting (2) at the right wheel motor. Plug hydraulic tube (3) and cap fitting (2). 4 TN347 Figure -20. Disconnect tube () from tee fitting (4). Plug hydraulic tube () and cap tee fitting (4).. Bypass seat switch. 7. Ensure park brake is engaged. Figure -22: Left Wheel Motor Test Oil Blocked to Right Wheel Motor and Traction Metering, and Wheel Motors Restrained NOTE TN3472 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 9. Start engine and run at full throttle (3400 rpm ± 0) Rev A -27

28 POWER TRAIN! CAUTION Right Wheel Motor Test Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 11. Move traction lever to the mow position. 12. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record left wheel motor loaded flow. 13. Open flow meter valve, return traction lever to the neutral position, and stop engine. 14. Calculate left wheel motor leakage. (Step 10 of previous test Step 12 / Step 10 of previous test x 100 = Leak Percentage) Is left wheel motor leakage 10% or less? YES Left wheel motor is good. Proceed to step 1. NO Proceed to next question. Is left wheel motor leakage 11% to 20%? YES Left wheel motor is marginal. Additional testing is required. Proceed to step 1. NO Proceed to next question. Is left wheel motor leakage 21% or more? YES Repair or replace left wheel motor. See Front Wheel Motor on page -39, then proceed to step Remove cap and plug and reconnect hydraulic tube (3) to fitting (2). 1. Proceed to Right Wheel Motor Test on page -28. TN347 Figure -23 Disconnect tube (7) from fitting (8) at left wheel motor. Plug hydraulic tube (7) and cap fitting (8). 17. Open flow meter valve completely before starting engine. 8 TN3473 Figure -24: Right Wheel Motor Test Oil Blocked to Left Wheel Motor and Traction Metering, and Wheel Motors Restrained NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 18. Start engine and run at full throttle (3400 rpm ± 0) Rev A

29 POWER TRAIN! CAUTION Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. 19. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 20. Move traction lever to the mow position. 21. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record right wheel motor loaded flow. 22. Open flow meter valve, return traction lever to the neutral position, and stop engine. 23. Calculate right wheel motor leakage. (Step 10 of control valve section test Step 12 / Step 10 of control valve section test x 100 = Leak Percentage) Is right wheel motor leakage 10% or less? YES Right wheel motor is good. Proceed to step 24. NO Proceed to next question. Is right wheel motor leakage 11% to 20%? YES Right wheel motor is marginal. Additional testing is required. Proceed to step 24. NO Proceed to next question. Is right wheel motor leakage 21% or more? YES Repair or replace right wheel motor. See Front Wheel Motor on page -39, then proceed to step Remove plug from hydraulic tube () and cap from fitting (4). 2. Reconnect hydraulic tube () to fitting (4). 2. Proceed to Traction Metering Test on page -29. Traction Metering Test See Figures -2 and -2. IMPORTANT This test works together with the Traction System Test, Gear Pump 1 Test, Control Test, and Wheel Motors Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Caps Plugs Wheel Restraints 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Wheel Motors Test on page -2, leaving flow meter connected and oil blocked to left wheel motor as outlined. 1 2 TN348 Figure Disconnect tube (2) from fitting (1). Plug hydraulic tube (2) and cap fitting (1) Rev A -29

30 POWER TRAIN 4. Open flow meter valve completely before starting engine. 11. Calculate traction metering valve leakage. (Step 10 of control valve section test Step 12 / Step 10 of control valve section test x 100 = Leak Percentage) Figure -2: Traction Metering Test Oil Blocked to Wheel Motors and Wheel Motors Restrained NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results.. Start engine and run at full throttle (3400 rpm ± 0).! CAUTION TN3484 Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. Is traction metering valve leakage 10% or less? YES Traction metering valve is good. Proceed to step 12. NO Proceed to next question. Is traction metering valve leakage 11% to 20%? YES Traction metering valve is marginal. Proceed to step 12. NO Proceed to next question. Is traction metering valve leakage 21% or more? YES Repair or replace traction metering valve. See Traction Metering on page -38, then proceed to step Remove plug from hydraulic tube (2) and cap from fitting (1). 13. Reconnect hydraulic tube (2) to fitting (1). 14. (See Figure -23.) Remove plug from hydraulic tube (7) and cap from fitting (8). 1. Reconnect hydraulic tube (7) to fitting (8). 1. Remove wheel restraints from front wheels. 17. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 18. Install and connect all components as noted prior to test. 19. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 20. Start engine. hydraulic system for leaks. Repair as necessary.. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or 0% of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 7. Move traction lever to the mow position. 8. Fully engage the traction pedal. 9. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record traction metering valve loaded flow. 10. Open flow meter valve, release the traction pedal, return traction lever to the neutral position, and stop engine Rev A

31 POWER TRAIN Repair Gear Pump Removal and Installation Diesel Model See Figure Park the mower safely. (See Park Mower Safely on page 1-.) 2. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) Installation Notes Anti-Seize Compound Loctite 242 (Blue) Required Materials Install gear pump by reversing the order of removal. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Apply anti-seize compound to gear pump shaft. Tighten screws (1) to lb-ft (23 28 N m). Apply Loctite 242 (Blue) to threads of screws (1) prior to assembly. Tighten inlet port fittings () to 37 lb-ft (0 N m). Tighten outlet port fittings (9) to 18 lb-ft (2 N m). Tighten outlet port fitting (10) to 2 lb-ft (70 N m). Pressure filter the traction system. (See Portable In-Line Filter on page -.) Replace hydraulic oil filter. (See Hydraulic Oil Filter on page -4.) Refill hydraulic oil tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. for leaks and repair as necessary. hydraulic oil level and add if necessary. Figure -27 TN348 NOTES Label all hydraulic hoses before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination. 3. Remove hose clamps () and disconnect hydraulic hoses (3 and 4) from fittings (). 4. Disconnect hydraulic hoses (11, 12, 13, 14, and 1).. Support gear pump (8) with suitable lifting device.. Remove two screws (1) and lock washers (2). 7. Remove gear pump (8). 8. Remove key (7) from gear pump shaft. 9. Remove fittings (, 9, and 10) from gear pump (8) Rev A -31

32 POWER TRAIN Gasoline Models See Figure -28. NOTE The -section gear pump is shown, 4-section gear pump is similar. 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) NOTES Label all hydraulic hoses before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination. 3. Remove hose clamps (2) and disconnect hydraulic hoses (1 and 3) from fittings (4). 4. Disconnect hydraulic hoses (12, 13, 14, 1, and 1).. Remove pump adapter cover (7).. Loosen set screw (). 7. Support gear pump (17) with suitable lifting device. 8. Remove two screws (9) and lock washers (8). 9. Remove gear pump (17). 10. Remove key () from gear pump shaft. Figure -28 TN Remove fittings (4, 10, and 11) from gear pump (17) Rev A

33 POWER TRAIN Installation Notes Required Materials Anti-Seize Compound Loctite 242 (Blue) Install gear pump by reversing the order of removal. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Apply anti-seize compound to gear pump shaft. Apply Loctite 242 (blue) to threads of set screw () and tighten set screw to lb-in. (1 18 N m). Tighten screws (10) to lb-ft (23 28 N m). Tighten inlet port fittings (4) to 37 lb-ft (0 N m). Tighten outlet port fittings (10) to 18 lb-ft (2 N m). Tighten outlet port fitting (11) to 2 lb-ft (70 N m). Pressure filter the traction system. (See Portable In-Line Filter on page -.) Replace hydraulic oil filter. (See Hydraulic Oil Filter on page -4.) Refill hydraulic oil tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. for leaks and repair as necessary. hydraulic oil level and add if necessary Rev A -33

34 POWER TRAIN Gear Pump (-) Disassembly, Inspection, and Assembly See Figures -29 and Retaining Ring 7 Key 13 Splined Connecting Shaft 19 Body 2 Washer (8) 2 Shaft Seal 8 Drive Shaft 14 Dowel Pin 20 Driven Gear 2 Retaining Screw (4) 3 Front Cover 9 Body Seal 1 Backup Ring 21 Driven Gear 27 Driven Gear 4 Antiextrusion 10 Dowel Pin 1 Seal 22 Drive Gear Seal 11 Body 17 Thrust Plate 23 Body Thrust Plate 12 Flange 18 Drive Shaft 24 Rear Cover Figure -29 TN Rev A

35 POWER TRAIN Disassembly Notes Do not disassemble pump for repair unless test procedures indicate internal leakage. Never pry components apart. Use a soft-faced hammer, and gently tap housing and shaft to separate pump bodies. Scribe or mark the pump bodies and end covers before disassembly to aid in assembly. Recommended method of marking body sections is to use a fine point metal punch, making one indentation for section 1, two indentations for section 2, etc.. Inspect seal kit components (2, 4,, 9, 1, and 1) for cracks, nicks, burrs, and excessive wear. Inspect surfaces for scoring, galling, and scratches. Replace as necessary. 7. Inspect remaining gear pump components for excessive wear or damage. Replace gear pump if necessary. Assembly Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Figure After removing retaining screws, disassemble pump, one section at a time. Before removing gear set, mark a line across meshing teeth to ensure that gears are reassembled in the same position. 2. Place parts, in assembly order, on a clean work area as they are removed. 3. Discard seals as they are removed. NOTICE TN1384 It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. 4. Clean all parts using clean solvent, and dry using compressed air.. Inspect all parts for cracks, nicks, burrs, and excessive wear. Inspect for scoring, galling, and scratches on surfaces. Damage or excessive wear to gear pump components other than seal kit components (2, 4,, 9, 1, and 1) requires gear pump replacement. Required Materials Seal Kit (Jacobsen PN 4181) Assemble the gear pump by reversing the order of disassembly. Use a new seal kit during assembly. Apply a coat of clean hydraulic oil to all parts to ease assembly. Assemble pump, one section at a time, building up from flange section. Remove alignment mark from gear sets after gears have been installed with teeth in proper mesh. Make sure that bushing sets are correctly installed to properly position the high pressure seals. Rotate drive shaft by hand after assembling each section to make sure there is no binding between parts; do not force. Use extreme care when installing shaft seal. Seal must seat squarely in seal bore. Use caution not to damage seal when installing cover over pump shaft. Install retaining screws (2) finger tight and rotate drive shaft to make sure it turns freely. Tighten retaining screws (2) evenly in steps to a final torque of 2 lb-ft (70 N m) and check rotation of pump drive shaft. Lubricate pump through ports with clean hydraulic oil prior to installing Rev A -3

36 POWER TRAIN Gear Pump (4-) Disassembly, Inspection, and Assembly See Figures -31 and Retaining Ring 7 Key 13 Splined Connecting Shaft 19 Body 2 Washer (8) 2 Shaft Seal 8 Drive Shaft 14 Dowel Pin 20 Driven Gear 2 Retaining Screw (4) 3 Front Cover 9 Body Seal 1 Backup Ring 21 Driven Gear 27 Driven Gear 4 Antiextrusion 10 Dowel Pin 1 Seal 22 Drive Gear Seal 11 Body 17 Thrust Plate 23 Body Thrust Plate 12 Flange 18 Drive Shaft 24 Rear Cover Figure -31 TN Rev A

37 POWER TRAIN Disassembly Notes Do not disassemble pump for repair unless test procedures indicate internal leakage. Never pry components apart. Use a soft-faced hammer, and gently tap housing and shaft to separate pump bodies. Scribe or mark the pump bodies and end covers before disassembly to aid in assembly. Recommended method of marking body sections is to use a fine point metal punch, making one indentation for section 1, two indentations for section 2, etc.. Inspect seal kit components (2, 4,, 9, 1, and 1) for cracks, nicks, burrs, and excessive wear. Inspect surfaces for scoring, galling, and scratches. Replace as necessary. 7. Inspect remaining gear pump components for excessive wear or damage. Replace gear pump if necessary. Assembly Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Figure After removing retaining screws, disassemble pump, one section at a time. Before removing gear set, mark a line across meshing teeth to ensure that gears are reassembled in the same position. 2. Place parts, in assembly order, on a clean work area as they are removed. 3. Discard seals as they are removed. NOTICE TN1384 It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. 4. Clean all parts using clean solvent, and dry using compressed air.. Inspect all parts for cracks, nicks, burrs, and excessive wear. Inspect for scoring, galling, and scratches on surfaces. Damage or excessive wear to gear pump components other than seal kit components (2, 4,, 9, 1, and 1) requires gear pump replacement. Required Materials Seal Kit (Jacobsen PN 4180) Assemble the gear pump by reversing the order of disassembly. Use a new seal kit during assembly. Apply a coat of clean hydraulic oil to all parts to ease assembly. Assemble pump, one section at a time, building up from flange section. Remove alignment mark from gear sets after gears have been installed with teeth in proper mesh. Make sure that bushing sets are correctly installed to properly position the high pressure seals. Rotate drive shaft by hand after assembling each section to make sure there is no binding between parts; do not force. Use extreme care when installing shaft seal. Seal must seat squarely in seal bore. Use caution not to damage seal when installing cover over pump shaft. Install retaining screws (2) finger tight and rotate drive shaft to make sure it turns freely. Tighten retaining screws (2) evenly in steps to a final torque of 2 lb-ft (70 N m) and check rotation of pump drive shaft. Lubricate pump through ports with clean hydraulic oil prior to installing Rev A -37

38 POWER TRAIN Traction Metering Removal and Installation See Figures -33 and Park the mower safely. (See Park Mower Safely on page 1-.) 2. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) Installation Notes Install traction metering valve by reversing the order of removal. NOTE The traction metering valve is located under the floorboard, next to the right wheel motor. 3. Thoroughly clean the valve, espeally the area surrounding hydraulic hoses, tubes, and fittings. NOTES Figure -33 TN3488 Label all hydraulic hoses and tubes before disconnecting to aid in installation. Close all openings with caps or plugs to prevent contamination. 4. Disconnect hydraulic hoses (,, and 8).. Remove port A fitting (4), port B fitting (7), and port C fitting (9) from traction metering valve (3).. Support the traction metering valve (3). 7. Remove two mounting screws (1) and lock washers (2). 8. Remove traction metering valve (3) TN3807 Figure -34 Ensure traction metering valve spool (11) does not contact frame (10). Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Tighten port A fitting (4) and port C fitting (9) to 30 lb-ft (41 N m). Tighten port B fitting (7) to 3 lb-ft (47 N m). Replace hydraulic oil filter. (See Hydraulic Oil Filter on page -4.) Refill hydraulic oil tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary. Adjust traction pedal. (See Traction Pedal Adjustment on page 9-.) Rev A

39 POWER TRAIN Front Wheel Motor Removal and Installation See Figure Park the mower safely. (See Park Mower Safely on page 1-.) 2. Remove front wheel. (See Front Wheel on page 9-18.) 3. Remove brake and front wheel hub. (See Brake and Front Wheel Hub on page 9-19.) Installation Notes Install front wheel motor by reversing the order of removal. Tighten inlet and outlet fittings ( and 7) to 30 lb-ft (41 N m). Pressure filter the traction system upon start-up if metal debris is found in system oil or motor. (See Portable In-Line Filter on page -.) hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) Figure -3 TN3489 NOTES Label all hydraulic hoses before disconnecting to ensure correct installation. Plug hydraulic hoses after disconnecting to prevent the loss of hydraulic oil. 4. Disconnect hoses (1 and 8).. Support front wheel motor () and remove four mounting screws (2), lock washers (3), and nuts (4).. Remove front wheel motor (). 7. Remove, inspect, and replace inlet and outlet fittings ( and 7) as necessary Rev A -39

40 POWER TRAIN Disassembly, Inspection, and Assembly See Figure Seal Thrust Washer 11 Seal Ring 1 Manifold 2 Bearing 7 Thrust Bearing 12 Drive Link 17 Wear Plate 3 Housing Assembly 8 Bearing 13 Speal Bolt 18 Rotor Assembly 4 Backup Ring 9 Coupling Shaft 14 End Cover 19 Commutator Shaft Seal 10 Thrust Bearing 1 Commutator Ring 20 Bonded Ring Figure -3 TN3490 NOTES Do not remove thrust washer (), thrust bearing (7), or bearing (8) unless they are damaged and will be replaced. Use care to keep rotor assembly (18) components together during disassembly and assembly. 1. Disassemble front wheel motor as shown. 2. Place parts, in assembly order, on a clean work area as they are removed Rev A

41 POWER TRAIN NOTICE It is important that motor parts are marked and placed in assembly order to aid in assembly. It is important that all motor parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Inspection Notes Keeping parts in assembly order, clean and air dry each item for inspection. Inspect for worn or defective parts. Look for metal chips or slivers during cleaning (an indication of damage to pump or other hydraulic component). Inspect all parts for cracks, nicks, burrs, and excessive wear. Inspect for scoring, galling, and scratches on surfaces. Replace parts as necessary. Assembly Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Required Materials Seal Kit (Jacobsen PN 473) Assemble the front wheel motor by reversing the order of disassembly. Use new seal kit during assembly. Lubricate all seal rings prior to assembly. Position bonded ring (20) into commutator (19) as shown in Figure -3. Pressure filter the traction system upon start-up if metal debris is found in system oil or motor. (See Portable In-Line Filter on page -.) Rev A -41

42 POWER TRAIN Rev A

43 Chapter Hydraulics Spefications Test Spefications Repair Spefications Hydraulic Hose, Tube, and Fitting General Instructions O-Ring Installation Hydraulic Hose Installation Hydraulic Service Tools Portable In-Line Filter Digital Hydraulic Tester Hydraulic Flowmeter Digital Pressure Gauge Kit Hydraulic Hose Kit Hydraulic Test Fitting Kit Blocking Disk Set Component Location Hydraulic Schematic Greens King IV Plus Hydraulic Schematic Greens King IV Theory of Operation and Diagnostic Information Steering Circuit Schematic and Theory of Operation Steering Circuit Schematic Raise Circuit Schematic and Theory of Operation Raise Circuit Schematic Lower Circuit Schematic and Theory of Operation Lower Circuit Schematic Mow Circuit Schematic and Theory of Operation Mow Circuit Schematic Backlap Circuit Schematic and Theory of Operation Backlap Circuit Schematic Field Test Procedures Preliminary s Lift Cylinder Leakage Test Steering Leakage Test Reel Motor Tests Rev A -1

44 Instrument Test Procedures Instrument Test Overview Left Cutting Unit Circuit Test Gear Pump 4 Test Control Test Left Reel Motor Test Center Cutting Unit Circuit Test Gear Pump 3 Test Control 4 Test Center Reel Motor Test Right Cutting Unit Circuit Test Gear Pump 2 Test Control 3 Test Right Reel Motor Test Control 2 Test Gear Pump Test Steering Relief Pressure Test Steering Relief Adjustment Repair Hydraulic Oil Tank Drain Procedure Hydraulic Oil Filter Hydraulic Oil Tank Backlap Load Control Control Rear Lift Cylinder Front Lift Cylinder Rev A

45 Spefications Test Spefications Spefications Gear Pump 1 Flow gpm (lpm) 8.7 (32.8) at 3400 rpm Gear Pump s 2 Flow gpm (lpm). (21.2) at 3400 rpm Steering Relief Pressure Setting psi (bar) 921 ± 10% (4 ± 10%) Left Reel Relief Pressure Setting psi (bar) 100 ± 10% (103 ± 10%) Center Reel Relief Pressure Setting psi (bar) 100 ± 10% (103 ± 10%) Raise/Right Reel Relief Pressure Setting psi (bar) 1700 ± 10% (117 ± 10%) Lower Relief Pressure Setting psi (bar) 1200 ± 10% (83 ± 10%) Hydraulic Leakage Percentage Ranges 0 10% = Good 11 20% = Marginal 21% and Beyond = Bad Repair Spefications Spefications Backlap Fitting Torque lb-ft (N m) 2 (34) Load Control Fitting Torque lb-ft (N m) 17 (23) Control Ports A and B Fitting lb-ft (N m) 90 (122) Torque Control Port P1 Fitting Torque lb-ft (N m) (7) Control Port P2 Fitting Torque lb-ft (N m) 2 (34) Control 4 Port P3 Fitting Torque lb-ft (N m) 2 (34) Control s 3 Ports A and B Fitting lb-ft (N m) 48 () Torque Control 2 Ports A and B Fitting lb-ft (N m) 2 (34) Torque Control 1 Port P4 Fitting Torque lb-ft (N m) 2 (34) Control Port T1 Fitting Torque lb-ft (N m) 33 (4) Rear Lift Cylinder Hose and Fitting Torque lb-ft (N m) 2 (34) Front Lift Cylinder Hose and Fitting Torque lb-ft (N m) 2 (34) Rev A -3

46 Hydraulic Hose, Tube, and Fitting General Instructions O-Ring Installation Always install new O-rings. On hoses with O-ring fittings, make sure O-rings are properly seated before tightening. O-rings should be lubricated with the fluid to be used in the system prior to assembly. Boss Fitting O-Ring Installation 3 TN407 1 Tubing O.D. or Hose I.D. 2 O-Ring 3 Thread Size O-Ring Seal Kits SAE Boss O-Ring Kit Jacobsen PN O-Ring Face Seal (ORS) O-Ring Kit PN Common O-Ring Sizes Kit PN Replacement O-Rings for ORS (Face Seal) Fittings ORS (Face Seal) Tube Size ORS (Face Seal) O-Ring Size Jacobsen Part Number TN4097 Replacement O-Rings for O-Ring Boss Fittings Tubing O.D. or Hose I.D. Thread Size Hydraulic Hose Installation Jacobsen Part Number 1/8 / /1 3/ /4 7/ /1 1/ /8 9/ /2 3/ /8 7/ /4 1-1/ /8 1-3/ / /4 1-/ /2 1-7/ / Hold the fixed portion of the hose coupling with one wrench; use a second wrench to tighten or loosen the hose nut. This will avoid damaging the fitting seal. When tightening a hose, do not permit the hose to twist; hold the hose in a normal straight position. When installing hoses, place fittings at angles to avoid contact with fixed parts when turning. Make sure hoses are assembled to proper A and B ports on components. Hydraulic Hose and Tube Torque Values Size lb-ft N m Dash Fractional Min Max Min Max -4 1/ / / / / / / Rev A

47 Hydraulic Service Tools NOTE The hydraulic service tools listed here can be obtained from K-Line Industries at Digital Hydraulic Tester Part Number AT40031 Portable In-Line Filter Part Number JAC097 TN4288 When hydraulic components fail internally, debris from the failed component can spread throughout the hydraulic system and cause additional damage. This situation can be magnified when dealing with a closed-loop traction system, where oil is not filtered. In the event of a traction system component failure, it is recommended that all traction system components be disassembled and cleaned, or filtered using a portable in-line filter available through your Jacobsen Dealer. The portable in-line filter should also be used when testing hydraulic systems or after replang a failed component. IMPORTANT TN428 Always install the in-line filter so oil flows through the filter before entering a component. Once filtering has begun, never reverse the flow of oil, or debris will re-enter the system. Features Flow up to 100 gpm (379 lpm) Pressure up to 000 psi (414 bar) Temperature up to 20 F (120 C) Digital display for flow and temperature Analog display for pressure Flow accuracy 1% of full scale Hydraulic Flow Meter Part Number AT40002 TN4287 Features Glycerin filled pressure gauge Presion needle-type load valve 4 40 gpm (1 1 lpm) flow range Pressure up to 000 psi (34 bar) -12 port size Rev A -

48 Digital Pressure Gauge Kit Part Number JAC10 Hydraulic Test Fitting Kit Part Number JAC001A Features Quick disconnect fittings Pressure up to 000 psi (34 bar) Includes one ft (12 cm) hose Hydraulic Hose Kit Part Number JAC001H NOTE This hydraulic hose kit is intended to be used with the JAC001A Hydraulic Test Fitting Kit. Contents TN4290 Two 8 ft (244 cm) 12 ORFS (F) x 10 ORFS (F) hoses Four 8 ft (244 cm) 10 ORFS (F) x 10 ORFS (F) hoses Two 8 ft (244 cm) 8 ORFS (F) x 10 ORFS (F) hoses NOTE For detailed component descriptions and sizes, please see the K-Line Industries website at Contents Twenty ORFS tee fittings in five sizes Eight ORFS 90 elbow fittings in four sizes Forty ORFS caps in five sizes Forty ORFS plugs in five sizes Six ORS reducer adapters in three sizes Sixteen ORS adapters in four sizes Eight blocking disks in four sizes Three JIC tee fittings in three sizes Three 4 in. (102 mm) jumper hoses in three sizes One ORS/male NPTF adapter One vented bushing One copper tube assembly Blocking Disk Set Part Number JAC001-1 TN4289 NOTE This blocking disk set is part of the JAC001A Hydraulic Test Fitting Kit. Contents Two - blocking disks Two -8 blocking disks Two -10 blocking disks Two -12 blocking disks Two -1 blocking disks Rev A

49 Page Intentionally Blank Rev A -7

50 Component Location See Figures -1 and TN340, TN3380, TN3242, TN340 1 Front Lift Cylinder 3 Hydraulic Oil Filter Rear Lift Cylinder 7 Center Backlap 2 Load Control 4 Center Backlap Left Backlap Figure -1: Component Location Left Side Rev A

51 Control 2 Hydraulic Oil Tank 3 Gear Pump Figure -2: Component Location Right Side TN333, TN Rev A -9

52 Hydraulic Schematic Greens King IV Plus See Figure -3. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Relief 100 psi Left Reel Relief 100 psi Center Reel Relief 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Traction Metering 0. Backlap 0. 4 A B A B A B A B A B Backlap 0. 3 Backlap Front Cylinder in in. Standard (See Note) P Raise/Right Reel Relief 1700 psi 1 V Load Control Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Figure -3 TN Rev A

53 Hydraulic Schematic Greens King IV See Figure -4. Gear Pump engine 3400 rpm Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Traction Metering 0. Backlap 0. 4 A B A B A B A B A B Backlap 0. 3 Backlap Front Cylinder in in. Standard (See Note) P Raise/Right Reel Relief 1700 psi 1 V Load Control Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Figure -4 TN Rev A -11

54 Theory of Operation and Diagnostic Information Steering Circuit Schematic and Theory of Operation System Conditions: Engine running Steering wheel turned to the right or left (left turn shown) Oil Supply to Steering Unit The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section of the gear pump is routed to the IN port of the steering unit. Steering Circuit Operating pressure oil enters the steering unit at the IN port, and is routed against the 921 psi (3. bar) relief valve, against the check valve, and to the steering valve. With the steering wheel in the neutral (straight ahead) position, the steering valve routes all of the operating pressure oil out of the steering unit through the OUT port, to the hydraulic oil filter, and then to the hydraulic tank. With the steering wheel turned to the left, the steering valve is moved, allowing oil to flow through the valve to the gerotor metering section. Oil is then routed through port LT of the steering unit to the rod side of the steering cylinder, retracting the rod, and moving the rear wheels in the desired direction. Oil from the piston end of the steering cylinder flows back into the steering unit through port RT, through the steering valve, against the check valve, against the 921 psi (3. bar) relief valve, and through the OUT port. Oil exiting the steering unit is routed to the hydraulic oil filter and then to the hydraulic tank. Circuit Relief The steering system is protected by the 921 psi (3. bar) implement relief valve. If the pressure on the pilot line of the relief valve reaches 921 psi (3. bar), the valve will open, dumping operating pressure oil through the OUT port of the steering unit to the hydraulic oil filter and then to the hydraulic tank Rev A

55 Steering Circuit Schematic See Figure -. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Traction Metering 0. Backlap 0. 4 A B A B A B A B A B Backlap 0. 3 Backlap Front Cylinder in in. Standard (See Note) P Raise/Right Reel Relief 1700 psi 1 V Load Control Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Metered Oil Figure - Inlet or Drain Oil Return Oil TN Rev A -13

56 Raise Circuit Schematic and Theory of Operation System Conditions: Engine running at fast idle Mower lift/lower pedal in the lift position NOTE The cutting unit motors will automatically shut off as the cutting units are raised. Oil Supply to the Lift/Lower The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 2 of the gear pump is routed to port P4 of the control valve. Raise Circuit Operating pressure oil supplied from section 2 of the gear pump enters the control valve at port P4. The oil flows against the 1700 psi (117 bar) relief valve, through the check valve, through the lift/lower valve, against the 1200 psi (83 bar) relief valve, and exits the control valve at port B. Oil from port B of the control valve is routed to the piston side of the front lift cylinder and through the load control valve. Oil flow to the piston side of the front lift cylinder raises the front cutting units. Oil flow from the load control valve is routed to the rod side of the rear cylinder. Oil flow to the rod side of the rear cylinder raises the rear cutting unit. Oil from the piston end of the rear lift cylinder flows to port P of the load control valve, through the 0.43 in. (1.09 mm) orifice, through the 0.09 in. (1. mm) orifice, and is then routed through the control valve, back to the hydraulic oil filter, and then to the hydraulic tank. The 0.43 in. (1.09 mm) orifice restricts the flow of oil, dampening the reaction of the rear cylinder retraction. Oil from the rod end of the front cylinder flows through the 0.09 in. (1. mm) orifice, and is then routed through the control valve, back to the hydraulic oil filter, and then to the hydraulic tank. The 0.09 in. (1. mm) orifice restricts the flow of oil, dampening the reaction of the front cylinder extension. Circuit Relief The raise rcuit is protected by the 1700 psi (117 bar) relief valve in the control valve. If the pressure on the pilot line of the relief valve reaches 1700 psi (117 bar), the valve will open, dumping operating pressure oil through port T1 of the control valve to the hydraulic oil filter, and then to the hydraulic tank Rev A

57 Raise Circuit Schematic See Figure -. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Traction Metering 0. Backlap 0. 4 A B A B A B A B A B Backlap 0. 3 Backlap Front Cylinder in in. Standard (See Note) P Raise/Right Reel Relief 1700 psi 1 V Load Control Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Metered Oil Figure - Inlet or Drain Oil Return Oil TN Rev A -1

58 Lower Circuit Schematic and Theory of Operation System Conditions: Engine running Mower lift/lower pedal in the mow position Oil Supply to the Lift/Lower The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 2 of the gear pump is routed to port P4 of the control valve. Lower Circuit Operating pressure oil supplied from section 2 of the gear pump enters the control valve at port P4. The oil flows against the 1700 psi (117 bar) relief valve, through the check valve, through the lift/lower valve, against the pilot of the 1200 psi (83 bar) relief valve, against the 1200 psi (83 bar) relief valve, and exits the control valve at port A. Oil from port A of the control valve flows through the 0.09 in. (1. mm) orifice and is routed to the rod end of the front cylinder. Oil flow to the rod end of the front cylinder lowers the front cutting units. The oil flow through the 0.09 in. (1. mm) orifice is also routed through the in. (1.09 mm) orifice to port P of the load control valve and to the piston end of the rear cylinder. Oil flow to the piston end of the rear cylinder lowers the rear cutting unit. Oil from the piston end of the front cylinder is routed through the control valve, back to the hydraulic oil filter, and then to the hydraulic tank. Oil flow from the rod end of the rear cylinder is routed through the load control valve, through the control valve, back to the hydraulic oil filter, and then to the hydraulic tank. The load control valve pressure lowers the rear cutting unit at a slower rate than the front cutting units and the oil pressure at the load control valve is adjustable. Adjusting the load control valve pressure increases or decrease the time delay between the front and rear cutting units when lowering the cutting units. Circuit Relief The lower system is protected by the 1200 psi (83 bar) relief valve in the control valve. If the pressure on the pilot line of the relief valve reaches 1200 psi (83 bar), the valve will open, dumping operating pressure oil through the right reel valve, through the control valve, to the hydraulic filter, and then to the hydraulic tank Rev A

59 Lower Circuit Schematic See Figure -7. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Traction Metering Backlap 4 A B A B A B A B A B Backlap 3 Backlap Front Cylinder in. Standard (See Note) Raise/Right Reel Relief 1700 psi 1 Load Control in. P V Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Metered Oil Figure -7 Inlet or Drain Oil Return Oil TN Rev A -17

60 Mow Circuit Schematic and Theory of Operation System Conditions: Engine running Cutting units lowered Traction lever in the mow position Reel control levers in the mow position The center and left reel rcuits are each protected by a 100 psi (103 bar) relief valve. The relief valve will open if the oil pressure in the rcuit reaches 100 psi (103 bar), routing oil through the control valve, and back to the hydraulic filter, then to the hydraulic tank. Oil Supply to the Reel s The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 2 of the gear pump is routed to port P4 of the control valve, operating pressure oil from section 3 of the gear pump is routed to port P3 of the control valve, and operating pressure oil from section 4 of the gear pump is routed to port P2 of the control valve. Mow Circuit Operating pressure oil supplied from section 2 of the gear pump enters the control valve at port P4, flows against the 1700 psi (117 bar) relief valve, through the check valve and against the lift/lower valve, through the lift/lower valve, against the 1200 psi (83 bar) relief valve, through the right reel valve, and exits the control valve at port A. Oil exiting port A is then routed to the right reel motor, driving the motor. Operating pressure oil supplied from section 3 of the gear pump enters the control valve at port P3, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, through the center reel valve, and exits the control valve at port A. Oil exiting port A is then routed to the center reel motor, driving the motor. Operating pressure oil supplied from section 4 of the gear pump enters the control valve at port P2, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, through the left reel valve, and exits the control valve at port A. Oil exiting port A is then routed to the left reel motor, driving the motor. Oil returning from the reel motors is routed to the backlap valves, through the control valve, and back to the hydraulic filter, then to the hydraulic tank. Circuit Relief The right reel rcuit is protected by the 1700 psi (117 bar) relief valve. The relief valve will open if the oil pressure in the rcuit reaches 1700 psi (117 bar), routing oil through the control valve, and back to the hydraulic filter, then to the hydraulic tank Rev A

61 Mow Circuit Schematic See Figure -8. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Center Reel Relief Relief Relief 100 psi 100 psi 100 psi Left Reel Center Reel Right Reel Lower Relief 1200 psi Lift/Lower Traction Metering 0. Backlap 0. 4 A B A B A B A B A B Backlap 0. 3 Backlap Front Cylinder in in. Standard (See Note) P Raise/Right Reel Relief 1700 psi 1 V Load Control Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Figure -8 Inlet or Drain Oil Return Oil TN Rev A -19

62 Backlap Circuit Schematic and Theory of Operation System Conditions: Engine running Cutting units lowered Park brake engaged Traction lever in the neutral position Reel control lever in the backlap position Backlap lockout switch in the on position Oil Supply to Reel The gear pump is driven by the engine. Hydraulic oil is drawn from the hydraulic oil tank by the gear pump. Operating pressure oil from section 2 of the gear pump is routed to port P4 of the control valve, operating pressure oil from section 3 of the gear pump is routed to port P3 of the control valve, and operating pressure oil from section 4 of the gear pump is routed to port P2 of the control valve. Oil returning from the reel motors is routed through the control valve, and back to the hydraulic filter, then to the hydraulic tank. Circuit Relief The right reel rcuit is protected by the 1700 psi (117 bar) relief valve. The relief valve will open if the oil pressure in the rcuit reaches 1700 psi (117 bar), routing oil through the control valve, and back to the hydraulic filter, then to the hydraulic tank. The center and left reel rcuits are protected by the 100 psi (103 bar) relief valve. The relief valve will open if the oil pressure in the rcuit reaches 100 psi (103 bar), routing oil through the control valve, and back to the hydraulic filter, then to the hydraulic tank. Backlap Circuit Operating pressure oil supplied from section 2 of the gear pump enters the control valve at port P4, flows against the 1700 psi (117 bar) relief valve, through the check valve and against the lift/lower valve, through the lift/lower valve, against the 1200 psi (83 bar) relief valve, through the right reel valve, and exits the control valve at port B. Oil exiting port B is routed to the backlap valve and right reel motor, driving the motor in the reverse direction. Adjusting the backlap valve adjusts the amount of operating pressure oil that returns to the hydraulic tank, thus controlling the speed of the reel motor. Operating pressure oil supplied from section 3 of the gear pump enters the control valve at port P3, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, through the center reel valve, and exits the control valve at port B. Oil exiting port B is routed to the backlap valve and center reel motor, driving the motor in the reverse direction. Adjusting the backlap valve adjusts the amount of operating pressure oil that returns to the hydraulic tank, thus controlling the speed of the reel motor. Operating pressure oil supplied from section 4 of the gear pump enters the control valve at port P2, flows against the 100 psi (103 bar) relief valve, against the pilot of the relief valve, through the left reel valve, and exits the control valve at port B. Oil exiting port B is routed to the backlap valve and left reel motor, driving the motor in the reverse direction. Adjusting the backlap valve adjusts the amount of operating pressure oil that returns to the hydraulic tank, thus controlling the speed of the reel motor Rev A

63 Backlap Circuit Schematic See Figure -9. Steering Unit LT Gear Pump IN Steering Cylinder RT engine 3400 rpm Relief 921 psi OUT Control T1 Traction P1 P2 P3 P4 Traction Left Reel Relief Relief 100 psi 100 psi Left Reel Center Reel Center Reel Relief 100 psi Lower Relief 1200 psi Right Reel Lift/Lower Traction Metering 0. Backlap 0. 4 A B A B A B A B A B Backlap 0. 3 Backlap Front Cylinder in in. Standard (See Note) P Raise/Right Reel Relief 1700 psi 1 V Load Control Wheel Motors Left Reel Motor Center Reel Motor Right Reel Motor Rear Cylinder C Tank Fill Cap Assembly 20 Micron Filter 20 Micron Filter 2 psi Crack Bypass Hydraulic Oil Filter Note: Optional 0.02 in. Soft Drop Hydraulic Tank Operating Pressure Oil Metered Oil Figure -9 Inlet or Drain Oil Return Oil TN Rev A -21

64 Field Test Procedures When a hydraulic system failure occurs, some simple effective tests can be performed prior to using a test instrument. The results of these tests can lead you to the suspected component failure. More extensive test procedures, using test instruments, are presented later in this section. (See Instrument Test Procedures on page -2.) Preliminary s Perform the following checks prior to beginning any tests. 1. the hydraulic oil reservoir for proper fluid level, the presence of air or water, and unusual odor. 2. all hoses, tubes, and fittings for leaks. Tighten as needed. 3. Eliminate all mechanical issues prior to starting hydraulic tests. Lift Cylinder Leakage Test See Figures -10 through -12.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Figure Raise front cutting units about 7% up so that cam roller (2) remains in contact with lift cam surface (3). Ensure cam roller is not in contact with lift cam surface (1). 4. Park the mower safely. (See Park Mower Safely on page 1-.). Support all cutting unit lift arms. NOTE Steps through 9 are for testing the front lift cylinder only. For testing the rear lift cylinder, proceed to step TN342 NOTE Ensure lift cylinders are properly adjusted before performing lift cylinder leakage test. (See Front Lift Cylinder Adjustment on page 8-18 and Rear Lift Cylinder Adjustment on page 8-19.) 1. Start engine. Operate hydraulic system until oil temperature is at F (49 C). 2. Fully raise the center cutting unit. TN330 Figure -11. Disconnect hose () from front lift cylinder piston end port (4). 7. Install cap on hose (). 8. Install plug in front lift cylinder piston end port (4). 9. Proceed to step Rev A

65 . Steering Leakage Test See Figure Operate hydraulic system until oil temperature is at F (49 C). 2. Turn steering wheel fully left against stop. 3. Park the mower safely. (See Park Mower Safely on page 1-.) Figure Support all cutting unit lift arms. 11. Disconnect hose (7) from rear lift cylinder rod end elbow fitting (). 12. Install plug in hose (7). 13. Install cap on rear lift cylinder rod end elbow fitting (). 14. Remove support from cutting unit lift arm being tested. After 1 minutes, does cutting unit drift down? YES Cylinder is bypassing oil. Repair or replace lift cylinder. (See Rear Lift Cylinder on page -2 or Front Lift Cylinder on page -7.) NO Repeat the test for all of the lift cylinders. If all cylinders pass test, the problem may be in the control valve or load control valve. Proceed to step Support all cutting unit lift arms. NOTE 1. Steps 17 and 18 are for the front lift cylinder only. For the rear lift cylinder, proceed to step Connect hose () to front lift cylinder piston end port (4). 18. Proceed to step Connect hose (7) to rear lift cylinder rod end elbow fitting (). 20. Start the engine and lower cutting units. 21. Stop the engine. 7 TN342 NOTE! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury Figure -13 TN348 Fuel tank and fuel tank support pan removed for picture clarity. 4. Disconnect hose (1) from steering cylinder fitting (2). Plug hose.. Position a suitable container under steering cylinder fitting (2) Rev A -23

66 ! WARNING Do not turn steering wheel to the right. Failure to follow appropriate safety precautions may result in death or serious injury.. With engine off, turn steering wheel fully left against stop. 7. for oil leakage in the drain pan. Is steering cylinder leakage a nominal amount of oil or less? YES Proceed to step 8. NO Repair or replace steering cylinder. (See Steering Cylinder on page 7-23.) 8. Disconnect and plug hose (3). 9. Start the engine and set engine speed to full throttle (3400 rpm ± 0). 10. Turn the steering wheel fully left, then fully right. Does the steering wheel continue to turn past stop with little or no resistance? YES NO Steering unit is faulty. Replace steering unit. (See Steering Unit (PN ) on page 7-.) Steering unit is good. Reel Motor Tests See Figure Park the mower safely. (See Park Mower Safely on page 1-.) NOTES! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Figure -14 Record location and routing of hydraulic hoses prior to removal and label all hydraulic hoses before disconnecting to ensure correct installation. Perform test for only one reel motor at a time. Left Reel Motor Test 1 2 TN Disconnect hose (4) from fitting () and hose (3) from fitting (). Connect hose (4) to fitting () and connect hose (3) to fitting (). 3. Start engine. Operate hydraulic system until oil temperature is at F (49 C). 4. Evaluate left cutting unit performance of mower. Has left cutting unit performance improved? YES 4 of gear pump is faulty. Inspect and repair or replace gear pump as necessary. (See Gear Pump on page -31.) NO Proceed to step Rev A

67 . Replace left reel motor with known good motor.. Evaluate left cutting unit performance of mower. Has left cutting unit performance improved? YES Left reel motor is faulty. Replace left reel motor. (See Reel Motor on page 8-32.) NO Control valve or backlap valve may be faulty. Proceed with an instrument test. (See Instrument Test Procedures on page -2.) 7. Reconnect all hoses as noted prior to testing. Has right cutting unit performance improved? YES Right reel motor is faulty. Replace right reel motor. (See Reel Motor on page 8-32.) NO Control valve or backlap valve may be faulty. Proceed with an instrument test. (See Instrument Test Procedures on page -2.) 19. Reconnect all hoses as noted prior to testing. Center Reel Motor Test 8. Disconnect hose (2) from fitting (1) and hose (3) from fitting (). Connect hose (2) to fitting () and connect hose (3) to fitting (1). 9. Start engine. Operate hydraulic system until oil temperature is at F (49 C). 10. Evaluate center cutting unit performance of mower. Has center cutting unit performance improved? YES 3 of gear pump is faulty. Inspect and repair or replace gear pump as necessary. (See Gear Pump on page -31.) NO Proceed to step Replace center reel motor with known good motor. 12. Evaluate center cutting unit performance of mower. Has center cutting unit performance improved? YES Center reel motor is faulty. Replace center reel motor. (See Reel Motor on page 8-32.) NO Control valve or backlap valve may be faulty. Proceed with an instrument test. (See Instrument Test Procedures on page -2.) 13. Reconnect all hoses as noted prior to testing. Right Reel Motor Test 14. Disconnect hose (2) from fitting (1) and hose (3) from fitting (). Connect hose (2) to fitting () and connect hose (1) to fitting (). 1. Start engine. Operate hydraulic system until oil temperature is at F (49 C). 1. Evaluate right cutting unit performance of mower. Has right cutting unit performance improved? YES 2 of gear pump is faulty. Inspect and repair or replace gear pump. (See Gear Pump on page -31.) NO Proceed to step Replace right reel motor with known good motor. 18. Evaluate right cutting unit performance of mower Rev A -2

68 Instrument Test Procedures Instrument Test Overview The following tests are spefically designed to approach hydraulic testing on a system level. Each component within the system represents a portion of the total system leakage. An internal leakage percentage for each component will be calculated and recorded, enabling the technian to view the system performance issue more completely. The test results will help the technian to determine which repairs will best remedy the performance issue experienced by the machine operator. The internal leakage percentage ranges are as follows: 0 10% = Good 11 20% = Marginal 21% and Beyond = Bad Example: Cutting Unit System Performance Complaint The machine operator reports the mower is not cutting correctly. Troubleshooting must first be performed to rule out a cutting unit adjustment issue. Once the issue is known to be component related, the entire cutting unit system is tested as outlined. The calculated system leakage is 28%, a result that requires the testing of individual components. This result can also be interpreted as the system is 72% effient. The remaining components in question are as follows: gear pump section 4, control valve section, and left reel motor. Following the procedures as outlined, test each individual component, then calculate and record leakage percentages. The results from this test reveal leakage of % in gear pump section 4,.3% in control valve section, and 20% in the left reel motor. Although all the components lend to the overall rcuit leakage, only the left reel motor, which is at the extreme end of the marginal range, would be considered for repair/replacement. Formulas: Cutting Unit Circuit Test No Load Flow Loaded Flow / No Load Flow x 100 = Leak Percentage Control and Reel Motor Loaded Flow from previous component Loaded Flow from current component / Loaded Flow from previous component x 100 = Leak Percentage Calculations: Cutting Unit Circuit Test No Load Flow = 10 gpm Loaded Flow = 7.2 gpm / 10 x 100 = Total Circuit Leakage 28% Gear Pump 4 Test No Load Flow = 10 gpm Loaded Flow = 9. gpm / 10 x 100 = Pump 4 Leakage % Control Test Loaded Flow from gear pump section 4 test = 9. gpm Loaded Flow from control valve section test = 9 gpm 9. 9 / 9. x 100 = Control Leakage.3% Left Reel Motor Test Loaded Flow from control valve section test = 9 gpm Loaded Flow from left reel motor test = 7.2 gpm / 9 x 100 = Left Reel Motor Leakage 20% Rev A

69 Left Cutting Unit Circuit Test See Figures -1 through -17. IMPORTANT This test works together with the Gear Pump 4 Test, Control Test, and Left Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Blocking Device or Tool 1. Park the mower safely. (See Park Mower Safely on page 1-.) Figure Install tee fitting () to fitting (1). 4. Connect test hose () of flow meter inlet and hose (2) to tee fitting (). NOTE Make sure hose end is under oil level in hydraulic tank to prevent aeration of oil.. Secure flow meter outlet hose (3) to the hydraulic tank fillneck.! WARNING Safely block cutting unit from rotating using a suitable device or tool. Failure to follow appropriate safety precaution may result in death or serious injury. 3 4 TN133. Install suitable blocking device or tool in left cutting unit, preventing the reel motor from turning. 7. Open flow meter valve (4) completely. 1 2 Figure Disconnect hose (2) from fitting (1). TN Rev A -27

70 Figure -17: Left Cutting Unit Circuit Test Left Reel Motor Blocked 8. Bypass seat switch. 9. Ensure park brake is engaged. NOTE TN3397 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 10. Start engine and run at full throttle (3400 rpm ± 0). 11. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (4) until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 12. Engage left reel control lever. 13. Read and record the left cutting unit rcuit no load flow. 14. Slowly close flow meter valve (4) until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the left cutting unit rcuit loaded flow. 1. Open flow meter valve, return left reel control lever to off position, and stop engine. 1. Calculate left cutting unit rcuit leakage. (Step 13 Step 14 / Step 13 x 100 = Leak Percentage) Is left cutting unit rcuit leakage 10% or less? YES The left cutting unit rcuit is good. Proceed to step 17. NO Proceed to next question. Is left cutting unit rcuit leakage 11% to 20%? YES The left cutting unit rcuit is marginal. Additional testing is required. Proceed to Gear Pump 4 Test on page -29. NO Proceed to next question. Is left cutting unit rcuit leakage 21% or more? YES Test individual components in left cutting unit rcuit for leakage. Proceed to Gear Pump 4 Test on page Remove blocking device or tool from left reel motor. 18. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 19. Install and connect all components as noted prior to test. 20. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 21. Start engine. hydraulic system for leaks. Repair as necessary Rev A

71 Gear Pump 4 Test See Figures -18 through -20. IMPORTANT This test works together with the Left Cutting Unit Circuit Test, Control Test, and Left Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Figure Disconnect hydraulic hose (1) from tee fitting (3). Plug hydraulic hose (1) and cap tee fitting (3). 4. Open flow meter valve (2) completely. 3 2 TN133 Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Left Cutting Unit Circuit Test on page -27, leaving flow meter connected as outlined. 1 TN3399 Figure -20: Gear Pump 4 Test Cap and Plug Between Gear Pump 4 and Control Figure -18 TN3393. Ensure park brake is engaged. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results.. Start engine and run at full throttle (3400 rpm ± 0) Rev A -29

72 ! CAUTION Do not exceed 100 psi (103 bar) as this test does not utilize system relief and damage may occur to hydraulic system components. 7. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (2) until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 8. Slowly close flow meter valve (2) until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record gear pump section 4 loaded flow. 9. Open flow meter valve and stop engine. 10. Calculate gear pump section 4 leakage. (Step 13 of previous test Step 8 / Step 13 of previous test x 100 = Leak Percentage) Is gear pump section 4 leakage 10% or less? YES Gear pump section 4 is good. Proceed to step 11. NO Proceed to next question. Is gear pump section 4 leakage 11% to 20%? YES Gear pump section 4 is marginal. Additional testing is required. Proceed to step 11. NO Proceed to next question. Is gear pump section 4 leakage 21% or more? YES Repair or replace gear pump section 4. See Gear Pump on page -31 then proceed to step 11. NO Proceed to step (See Figures -18 and -19.) Remove cap and plug and reconnect hydraulic hose (1) to tee fitting (3). 12. Proceed to Control Test on page -30. Control Test See Figures -21 through -23. IMPORTANT This test works together with the Left Cutting Unit Circuit Test, Gear Pump 4 Test, and Left Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Left Cutting Unit Circuit Test, leaving flow meter connected as outlined. 1 TN3297 Figure Disconnect hose (1) from fitting (2). Plug hydraulic hose (1) and cap fitting (2) Rev A

73 ! CAUTION Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. Figure Open flow meter valve (3) completely. 3 TN Use the flow meter to warm the hydraulic oil. Turn the flow meter valve (3) until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Engage left reel control lever. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the control valve section loaded flow. 11. Open flow meter valve, return left reel control lever to off position, and stop engine. 12. Calculate control valve section leakage. (Step 8 of previous test Step 10 / Step 8 of previous test x 100 = Leak Percentage) Is control valve section leakage 10% or less? YES NO Control valve section is good. Proceed to step 13. Proceed to next question. Is control valve section leakage 11% to 20%? YES Control valve section is marginal. Additional testing is required. Proceed to step 13. NO Proceed to next question. Figure -23: Control Test Cap and Plug at Left Reel Motor. Bypass seat switch.. Ensure park brake is engaged. NOTE TN3400 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0). Is control valve section leakage 21% or more? YES Repair or replace control valve section. See Control on page -9 then proceed to step 13.! CAUTION Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. 13. Open flow meter valve completely before starting engine. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 14. Start engine and run at full throttle (3400 rpm ± 0) Rev A -31

74 1. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 1. Engage left reel control lever. 17. Continue to close flow meter valve until zero flow is obtained and record left reel relief valve pressure. Is left reel relief pressure 100 psi ± 10% (103 ± 10% bar)? YES Left reel relief valve is good. Open flow meter valve, return left reel control lever to off position, and stop engine. Proceed to step 19. NO Proceed to step Adjust left reel relief valve by adding or removing shims as necessary. (See Disassembly, Inspection, and Assembly on page -1.) Close flow meter valve until zero flow is obtained and record left reel relief valve pressure. Can left reel relief valve be adjusted to relieve at 100 psi (103 bar)? YES Left reel relief valve is good. Open flow meter valve, return left reel control lever to off position, and stop engine. Proceed to step 19. NO Replace left reel relief valve. See Control on page -9 then proceed to step (See Figure -21.) Remove cap and plug and reconnect hydraulic hose (1) to left reel motor. 20. Proceed to Left Reel Motor Test on page -32. Left Reel Motor Test See Figures -24 and -2. IMPORTANT This test works together with the Left Cutting Unit Circuit Test, Gear Pump 4 Test, and Control Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Blocking Device or Tool 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Control Test, leaving flow meter connected as outlined. 3. Install suitable blocking device or tool in left cutting unit, preventing the reel motor from turning. 4. Bypass seat switch.. Ensure park brake is engaged. 1 Figure -24 TN Rev A

75 . Open flow meter valve (1) completely. 12. Calculate left reel motor leakage. (Step 10 of previous test Step 10 / Step 10 of previous test x 100 = Leak Percentage) Figure -2: Left Reel Motor Test Left Reel Motor Blocked NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0).! CAUTION TN3397 Do not exceed 100 psi (103 bar) as this test does not utilize system relief and damage may occur to hydraulic system components. Is left reel motor leakage 10% or less? YES The left reel motor is good. Proceed to step 13. NO Proceed to next question. Is left reel motor leakage 11% to 20%? YES The left reel motor is marginal. Proceed to step 13. NO Proceed to next question. Is left reel motor leakage 21% or more? YES Repair or replace left reel motor. See Reel Motor on page 8-32 then proceed to step Remove blocking device or tool from left cutting unit. 14. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 1. Install and connect all components as noted prior to test. 1. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 17. Start engine. hydraulic system for leaks. Repair as necessary. 8. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Engage left reel control lever. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the left reel motor loaded flow. 11. Open flow meter valve, return left reel control lever to off position, and stop engine Rev A -33

76 Center Cutting Unit Circuit Test See Figures -2 through -28. IMPORTANT This test works together with the Gear Pump 3 Test, Control 4 Test, and Center Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Blocking Device or Tool 1. Park the mower safely. (See Park Mower Safely on page 1-.) Figure Install tee fitting () to fitting (1). 4. Connect test hose () of flow meter inlet and hose (2) to tee fitting (). NOTE Make sure hose end is under oil level in hydraulic tank to prevent aeration of oil.. Secure flow meter outlet hose (3) to the hydraulic tank fillneck.! WARNING Safely block cutting unit from rotating using a suitable device or tool. Failure to follow appropriate safety precaution may result in death or serious injury. 3 4 TN Install suitable blocking device or tool in center cutting unit, preventing the reel motor from turning. 7. Open flow meter valve (4) completely. Figure Disconnect hose (2) from fitting (1). TN Rev A

77 Figure -28: Center Cutting Unit Circuit Test Center Reel Motor Blocked 8. Bypass seat switch. 9. Ensure park brake is engaged. NOTE TN3411 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 10. Start engine and run at full throttle (3400 rpm ± 0). 11. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 12. Engage center reel control lever. 13. Read and record the center cutting unit rcuit no load flow. 14. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the center cutting unit rcuit loaded flow. 1. Open flow meter valve, return center reel control lever to off position, and stop engine. 1. Calculate center cutting unit rcuit leakage. (Step 13 Step 14 / Step 13 x 100 = Leak Percentage) Is center cutting unit rcuit leakage 10% or less? YES The center cutting unit rcuit is good. Proceed to step 17. NO Proceed to next question. Is center cutting unit rcuit leakage 11% to 20%? YES The center cutting unit rcuit is marginal. Additional testing is required. Proceed to Gear Pump 3 Test on page -3. NO Proceed to next question. Is center cutting unit rcuit leakage 21% or more? YES Test individual components in center cutting unit rcuit for leakage. Proceed to Gear Pump 3 Test on page Remove blocking device or tool from center reel motor. 18. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 19. Install and connect all components as noted prior to test. 20. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 21. Start engine. hydraulic system for leaks. Repair as necessary Rev A -3

78 Gear Pump 3 Test See Figures -29 through -31. IMPORTANT This test works together with the Center Cutting Unit Circuit Test, Control 4 Test, and Center Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Figure Disconnect hydraulic hose (1) from tee fitting (3). Plug hydraulic hose (1) and cap tee fitting (3). 4. Open flow meter valve (2) completely. 3 2 TN133 Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Center Cutting Unit Circuit Test on page -34, leaving flow meter connected as outlined. 1 TN3412 Figure -31: Gear Pump 3 Test Cap and Plug Between Gear Pump 3 and Control 4 Figure -29 TN3393. Ensure park brake is engaged. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results.. Start engine and run at full throttle (3400 rpm ± 0) Rev A

79 ! CAUTION Do not exceed 100 psi (103 bar) as this test does not utilize system relief and damage may occur to hydraulic system components. 7. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 8. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record gear pump section 3 loaded flow. 9. Open flow meter valve and stop engine. 10. Calculate gear pump section 3 leakage. (Step 13 of previous test Step 8 / Step 13 of previous test x 100 = Leak Percentage) Is gear pump section 3 leakage 10% or less? YES Gear pump section 3 is good. Proceed to step 11. NO Proceed to next question. Is gear pump section 3 leakage 11% to 20%? YES Gear pump section 3 is marginal. Additional testing is required. Proceed to step 11. NO Proceed to next question. Is gear pump section 3 leakage 21% or more? YES Repair or replace gear pump section 3. See Gear Pump on page -31 then proceed to step 11. NO Proceed to step (See Figures -29 and -30.) Remove cap and plug and reconnect hydraulic hose (1) to tee fitting (3). 12. Proceed to Control 4 Test on page -37. Control 4 Test See Figures -32 through -34. IMPORTANT This test works together with the Center Cutting Unit Circuit Test, Gear Pump 3 Test, and Center Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Center Cutting Unit Circuit Test, leaving flow meter connected as outlined. 1 2 Figure -32 TN Rev A -37

80 3. Disconnect hose (1) from fitting (2). Plug hydraulic hose (1) and cap fitting (2).! CAUTION Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. Figure Open flow meter valve (3) completely. 3 TN Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Engage center reel control lever. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the control valve section 4 loaded flow. 11. Open flow meter valve, return center reel control lever to off position, and stop engine. 12. Calculate control valve section 4 leakage. (Step 8 of previous test Step 10 / Step 8 of previous test x 100 = Leak Percentage) Is control valve section 4 leakage 10% or less? YES NO Control valve section 4 is good. Proceed to step 13. Proceed to next question. Is control valve section 4 leakage 11% to 20%? YES Control valve section 4 is marginal. Additional testing is required. Proceed to step 13. NO Proceed to next question. Is control valve section 4 leakage 21% or more? YES Repair or replace control valve section 4. See Control on page -9 then proceed to step 13.! CAUTION Figure -34: Control 4 Test Cap and Plug at Center Reel Motor. Bypass seat switch.. Ensure park brake is engaged. NOTE TN3413 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0). Do not exceed 100 psi (103 bar) as damage may occur to hydraulic system components. 13. Open flow meter valve completely before starting engine. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 14. Start engine and run at full throttle (3400 rpm ± 0) Rev A

81 1. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 1. Engage center reel control lever. 17. Continue to close flow meter valve until zero flow is obtained and record center reel relief valve pressure. Is center reel relief pressure 100 psi ± 10% (103 ± 10% bar)? YES Center reel relief valve is good. Open flow meter valve, return center reel control lever to off position, and stop engine. Proceed to step 19. NO Proceed to step Adjust center reel relief valve by adding or removing shims as necessary. (See Disassembly, Inspection, and Assembly on page -1.) Close flow meter valve until zero flow is obtained and record center reel relief valve pressure. Can center reel relief valve be adjusted to relieve at 100 psi (103 bar)? YES Center reel relief valve is good. Open flow meter valve, return center reel control lever to off position, and stop engine. Proceed to step 19. NO Replace center reel relief valve. See Control on page -9 then proceed to step (See Figure -32.) Remove cap and plug and reconnect hydraulic hose (1) to center reel motor. 20. Proceed to Center Reel Motor Test on page -39. Center Reel Motor Test See Figures -3 and -3. IMPORTANT This test works together with the Center Cutting Unit Circuit Test, Gear Pump 3 Test, and Control 4 Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Blocking Device or Tool 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Control 4 Test, leaving flow meter connected as outlined. 3. Install suitable blocking device or tool in center cutting unit, preventing the reel motor from turning. 4. Bypass seat switch.. Ensure park brake is engaged. 1 Figure -3 TN Rev A -39

82 . Open flow meter valve (1) completely. 12. Calculate center reel motor leakage. (Step 10 of previous test Step 10 / Step 10 of previous test x 100 = Leak Percentage) Figure -3: Center Reel Motor Test Center Reel Motor Blocked NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0).! CAUTION TN3411 Do not exceed 100 psi (103 bar) as this test does not utilize system relief and damage may occur to hydraulic system components. Is center reel motor leakage 10% or less? YES The center reel motor is good. Proceed to step 13. NO Proceed to next question. Is center reel motor leakage 11% to 20%? YES The center reel motor is marginal. Proceed to step 13. NO Proceed to next question. Is center reel motor leakage 21% or more? YES Repair or replace center reel motor. See Reel Motor on page 8-32 then proceed to step Remove blocking device or tool from center cutting unit. 14. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 1. Install and connect all components as noted prior to test. 1. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 17. Start engine. hydraulic system for leaks. Repair as necessary. 8. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Engage center reel control lever. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the center reel motor loaded flow. 11. Open flow meter valve, return center reel control lever to off position, and stop engine Rev A

83 Right Cutting Unit Circuit Test See Figures -37 through -39. IMPORTANT This test works together with the Gear Pump 2 Test, Control 3 Test, and Right Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Blocking Device or Tool 1. Park the mower safely. (See Park Mower Safely on page 1-.) Figure Install tee fitting () to fitting (1). 4. Connect test hose () of flow meter inlet and hose (2) to tee fitting (). NOTE Make sure hose end is under oil level in hydraulic tank to prevent aeration of oil.. Secure flow meter outlet hose (3) to the hydraulic tank fillneck.! WARNING Safely block cutting unit from rotating using a suitable device or tool. Failure to follow appropriate safety precaution may result in death or serious injury. 3 4 TN Install suitable blocking device or tool in right cutting unit, preventing the reel motor from turning. 7. Open flow meter valve (4) completely. Figure Disconnect hose (2) from fitting (1). TN Rev A -41

84 Figure -39: Right Cutting Unit Circuit Test Right Reel Motor Blocked 8. Bypass seat switch. 9. Ensure park brake is engaged. NOTE TN3414 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 10. Start engine and run at full throttle (3400 rpm ± 0). 11. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 12. Engage right reel control lever. 13. Read and record the right cutting unit rcuit no load flow. 14. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the right cutting unit rcuit loaded flow. 1. Open flow meter valve, return right reel control lever to off position, and stop engine. 1. Calculate right cutting unit rcuit leakage. (Step 13 Step 14 / Step 13 x 100 = Leak Percentage) Is right cutting unit rcuit leakage 10% or less? YES The right cutting unit rcuit is good. Proceed to step 17. NO Proceed to next question. Is right cutting unit rcuit leakage 11% to 20%? YES The right cutting unit rcuit is marginal. Additional testing is required. Proceed to Gear Pump 2 Test on page -43. NO Proceed to next question. Is right cutting unit rcuit leakage 21% or more? YES Test individual components in right cutting unit rcuit for leakage. Proceed to Gear Pump 2 Test on page Remove blocking device or tool from right reel motor. 18. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 19. Install and connect all components as noted prior to test. 20. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 21. Start engine. hydraulic system for leaks. Repair as necessary Rev A

85 Gear Pump 2 Test See Figures -40 through -42. IMPORTANT This test works together with the Right Cutting Unit Circuit Test, Control 3 Test, and Right Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Figure Disconnect hydraulic hose (1) from tee fitting (3). Plug hydraulic hose (1) and cap tee fitting (3). 4. Open flow meter valve (2) completely. 3 2 TN133 Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Right Cutting Unit Circuit Test on page -41, leaving flow meter connected as outlined. 1 TN341 Figure -42: Gear Pump 2 Test Cap and Plug Between Gear Pump 2 and Control 3 Figure -40 TN3393. Ensure park brake is engaged. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results.. Start engine and run at full throttle (3400 rpm ± 0) Rev A -43

86 ! CAUTION Do not exceed 1700 psi (117 bar) as this test does not utilize system relief and damage may occur to hydraulic system components. 7. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 8. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the gear pump section 2 loaded flow. 9. Open flow meter valve and stop engine. 10. Calculate gear pump section 2 leakage. (Step 13 of previous test Step 8 / Step 13 of previous test x 100 = Leak Percentage) Is gear pump section 2 leakage 10% or less? YES Gear pump section 2 is good. Proceed to step 11. NO Proceed to next question. Is gear pump section 2 leakage 11% to 20%? YES Gear pump section 2 is marginal. Additional testing is required. Proceed to step 11. NO Proceed to next question. Is gear pump section 2 leakage 21% or more? YES Repair or replace gear pump section 2. See Gear Pump on page -31 then proceed to step 11. NO Proceed to step (See Figures -40 and -41.) Remove cap and plug and reconnect hydraulic hose (1) to tee fitting (3). 12. Proceed to Control 3 Test on page -44. Control 3 Test See Figures -43 through -4. IMPORTANT This test works together with the Right Cutting Unit Circuit Test, Gear Pump 2 Test, and Right Reel Motor Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Right Cutting Unit Circuit Test, leaving flow meter connected as outlined. 1 2 TN3401 Figure Disconnect hose (1) from fitting (2). Plug hydraulic hose (1) and cap fitting (2) Rev A

87 ! CAUTION Do not exceed 1700 psi (117 bar) as damage may occur to hydraulic system components. Figure Open flow meter valve (3) completely. 3 TN Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Engage right reel control lever. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the control valve section 3 loaded flow. 11. Open flow meter valve, return right reel control lever to off position, and stop engine. 12. Calculate control valve section 3 leakage. (Step 8 of previous test Step 10 / Step 8 of previous test x 100 = Leak Percentage) Is control valve section 3 leakage 10% or less? YES NO Control valve section 3 is good. Proceed to step 13. Proceed to next question. Is control valve section 3 leakage 11% to 20%? YES Control valve section 3 is marginal. Additional testing is required. Proceed to step 13. NO Proceed to next question. Figure -4: Control 3 Test Cap and Plug at Right Reel Motor. Bypass seat switch.. Ensure park brake is engaged. NOTE TN341 Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0). Is control valve section 3 leakage 21% or more? YES Repair or replace control valve section 3. See Control on page -9 then proceed to step 13.! CAUTION Do not exceed 1700 psi (117 bar) as damage may occur to hydraulic system components. 13. Open flow meter valve completely before starting engine. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 14. Start engine and run at full throttle (3400 rpm ± 0) Rev A -4

88 1. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 80 psi (9 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 1. Engage right reel control lever. 17. Continue to close flow meter valve until zero flow is obtained and record raise/right reel relief valve pressure. Is raise/right reel relief pressure 1700 ± 10% psi (117 ± 10% bar)? YES Raise/right reel relief valve is good. Open flow meter valve, return right reel control lever to off position, and stop engine. Proceed to step 19. NO Proceed to step Adjust raise/right reel relief valve by adding or removing shims as necessary. (See Disassembly, Inspection, and Assembly on page -1.) Close flow meter valve until zero flow is obtained and record raise/right reel relief valve pressure. Can raise/right reel relief valve be adjusted to relieve at 1700 psi (117 bar)? YES Raise/right reel relief valve is good. Open flow meter valve, return right reel control lever to off position, and stop engine. Proceed to step 19. NO Replace raise/right reel relief valve. See Control on page -9 then proceed to step (See Figure -43.) Remove cap and plug and reconnect hydraulic hose (1) to right reel motor. 20. Proceed to Right Reel Motor Test on page -4. Right Reel Motor Test See Figures -4 and -47. IMPORTANT This test works together with the Right Cutting Unit Circuit Test, Gear Pump 2 Test, and Control 3 Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Blocking Device or Tool 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Control 3 Test, leaving flow meter connected as outlined. 3. Install suitable blocking device or tool in right cutting unit, preventing the reel motor from turning. 4. Bypass seat switch.. Ensure park brake is engaged. 1 Figure -4 TN Rev A

89 . Open flow meter valve (1) completely. 12. Calculate right reel motor leakage. (Step 10 of previous test Step 10 / Step 10 of previous test x 100 = Leak Percentage) Figure -47: Right Reel Motor Test Right Reel Motor Blocked NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0).! CAUTION TN3414 Do not exceed 1700 psi (117 bar) as damage may occur to hydraulic system components. Is right reel motor leakage 10% or less? YES The right reel motor is good. Proceed to step 13. NO Proceed to next question. Is right reel motor leakage 11% to 20%? YES The right reel motor is marginal. Proceed to step 13. NO Proceed to next question. Is right reel motor leakage 21% or more? YES Repair or replace right reel motor. See Reel Motor on page 8-32 then proceed to step Remove blocking device or tool from right cutting unit. 14. Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 1. Install and connect all components as noted prior to test. 1. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 17. Start engine. hydraulic system for leaks. Repair as necessary. 8. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 70 psi (2 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Engage right reel control lever. 10. Slowly close flow meter valve until pressure reaches 112 psi (78 bar) or 7% of the relief valve rating is reached. Read and record the center reel motor loaded flow. 11. Open flow meter valve, return right reel control lever to off position, and stop engine Rev A -47

90 Control 2 Test See Figures -48 through -0. IMPORTANT This test works together with the Right Cutting Unit Circuit Test and Gear Pump 2 Test.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Figure Open flow meter valve (3) completely. 3 TN133 Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) Tee Fitting Cap Plug 1. Park the mower safely. (See Park Mower Safely on page 1-.) 2. Before performing this test, perform Right Cutting Unit Circuit Test, leaving flow meter connected as outlined. 1 2 TN372 Figure -0: Control 2 Test Cap and Plug at Control 2 Port A. Bypass seat switch.. Ensure park brake is engaged. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 7. Start engine and run at full throttle (3400 rpm ± 0). Figure Disconnect tube (2) from fitting (1). Plug hydraulic tube (2) and cap fitting (1) Rev A

91 ! CAUTION Do not exceed 1200 psi (83 bar) as damage may occur to hydraulic system components. 8. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 00 psi (41 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 9. Fully engage the lower/lift pedal to the lower position. 10. Slowly close flow meter valve until pressure reaches 900 psi (2 bar) or 7% of the relief valve rating is reached. Read and record the control valve section 2 loaded flow. 11. Open flow meter valve, release the lower/lift pedal, and stop engine. 12. Calculate control valve section 2 leakage. (Step 8 of Gear Pump 2 Test Step 10 / Step 8 of Gear Pump 2 Test x 100 = Leak Percentage) Is control valve section 2 leakage 10% or less? YES Control valve section 2 is good. Proceed to step 13. NO Proceed to next question. Is control valve section 2 leakage 11% to 20%? YES Control valve section 2 is marginal. Additional testing is required. Proceed to step 13. NO Proceed to next question. Is control valve section 2 leakage 21% or more? YES Repair or replace control valve section 2. See Control on page -9 then proceed to step 13.! CAUTION Do not exceed 1200 psi (83 bar) as damage may occur to hydraulic system components. 1. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 00 psi (41 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C); open valve fully after operating temperature is reached. 1. Fully engage the lower/lift pedal to the lower position. 17. Continue to close flow meter valve until zero flow is obtained and record lower relief valve pressure. Is lower relief pressure 1200 psi ± 10% (83 ± 10% bar)? YES Lower relief valve is good. Open flow meter valve, release the lower/lift pedal, and stop engine. Proceed to step 19. NO Proceed to step Adjust lower relief valve by adding or removing shims as necessary. (See Disassembly, Inspection, and Assembly on page -1.) Close flow meter valve until zero flow is obtained and record lower relief valve pressure. Can lower relief valve be adjusted to relieve at 1200 psi (83 bar)? YES Lower relief valve is good. Open flow meter valve, release the lower/lift pedal, and stop engine. Proceed to step 19. NO Replace lower relief valve. See Control on page -9 then proceed to step Disconnect and remove test equipment. Install all hoses, tubes, and fittings as noted prior to removal. 20. Install and connect all components as noted prior to test. 21. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 22. Start engine. hydraulic system for leaks. Repair as necessary. 13. Open flow meter valve completely before starting engine. NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 14. Start engine and run at full throttle (3400 rpm ± 0) Rev A -49

92 Gear Pump Test See Figures -1 through NOTE Before performing this test, perform field test procedures. (See Field Test Procedures on page -22.)! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. 4 TN139 Figure Connect flow meter inlet test hose () to fitting (1). 4. Connect flow meter outlet test hose (3) to hose (2).. Open flow meter valve (4) completely. Required Tools and Materials Flow Meter Test Hose 4000 psi (27 bar) 1. Park the mower safely. (See Park Mower Safely on page 1-.) 1 2 TN322 Figure -3: Gear Pump Test. Bypass seat switch. 7. Ensure park brake is engaged. Figure Disconnect hose (2) from fitting (1). TN3393 NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 8. Start engine and run at full throttle (3400 rpm ± 0).! CAUTION Do not exceed 921 psi (3. bar) as this test does not utilize system relief and damage may occur to hydraulic system components. 9. Use the flow meter to warm the hydraulic oil. Turn the flow meter valve until a reading of 40 psi (32 bar) or one half of the relief valve rating is reached. Warm oil to F (49 C) Rev A

93 10. Open flow meter valve completely. Read and record gear pump section no load flow. 11. Slowly close flow meter valve until pressure reaches 90 psi (47 bar) or 7% of the relief valve rating is reached. Read and record the steer pump loaded flow. 12. Open flow meter valve and stop engine. 13. Calculate gear pump section leakage. (Step 10 Step 11 / Step 10 x 100 = Leak Percentage) Is gear pump section leakage 10% or less? YES The gear pump section is good. Proceed to step 14. NO Proceed to next question. Is gear pump section leakage 11% to 20%? YES The gear pump section is marginal. Additional testing is required. (See Field Test Procedures on page -22.) NO Proceed to next question. Is gear pump section leakage 21% or more? YES Repair or replace gear pump section. (See Gear Pump on page -31.) 14. Disconnect and remove test equipment. Install all hoses and fittings as noted prior to removal. 1. Install and connect all components as noted prior to test. 1. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 17. Start engine. hydraulic system for leaks. Repair as necessary. Steering Relief Pressure Test See Figures -4 through -. NOTE Before performing this test, perform field test procedures. (See Field Test Procedures on page -22.)! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Pressure Gauge 2000 psi (138 bar) Test Hose 2000 psi (138 bar) Tee Fitting 1. Operate hydraulic system until oil temperature is at F (49 C). 2. Park the mower safely. (See Park Mower Safely on page 1-.) 1 2 Figure Disconnect hose (2) from fitting (1). TN Rev A -1

94 11. Stop engine. 3 TN127 Figure - 4. Connect tee fitting to hose (2) and fitting (1).. Connect test hose and pressure gauge (3) to tee fitting.. Bypass seat switch. 7. Ensure park brake is engaged. Is steering relief pressure 921 ± 10% psi (3. ± 10% bar)? YES Steering relief valve is good. Proceed to step 12. NO Test steer cylinder. (See Steering Leakage Test on page -23.) Adjust steering relief valve. (See Steering Relief Adjustment on page -2.) 12. Disconnect and remove test equipment. Install all hoses and fittings as noted prior to removal. 13. Install and connect all components as noted prior to test. 14. hydraulic oil level. Add oil as needed. (Refer to Parts and Maintenance Manual for correct oil spefications.) 1. Start engine. hydraulic system for leaks. Repair as necessary. Steering Relief Adjustment See Figures -7 and -8.! WARNING The hydraulic system is under pressure, and the oil will be hot. Always relieve pressure in the hydraulic system before performing service. Failure to follow appropriate safety precautions may result in death or serious injury. Required Tools and Materials Figure -: Steer Relief Pressure Test NOTE Verify engine rpm is within spefication (3400 rpm ± 0) to ensure accurate hydraulic test results. 8. Start engine and run at full throttle (3400 rpm ± 0).! CAUTION Do not run steer relief valve over relief longer than 10 seconds or damage may occur to hydraulic system components. 9. Turn the steering wheel fully right against stop. 10. Record pressure reading. TN323 Pressure Gauge 2000 psi (138 bar) Test Hose 2000 psi (138 bar) Tee Fitting 8 mm Allen Wrench NOTES This adjustment should be done in conjunction with steering relief valve pressure test. Figures -7 and -8 show steering unit PN Procedure is similar for steering unit PN Park the mower safely. (See Park Mower Safely on page 1-.) 2. Perform steering relief valve pressure test. (See Steering Relief Pressure Test on page -1.) Rev A

95 3. Remove steering wheel. (See Steering Wheel (Power Steering) on page 7-.) 4. Remove steering tower cover. (See Steering Tower Cover on page 7-21.) TN3780 Figure -7. Remove four screws (2) and lock washers (3), and remove steering column (1) from steering unit (4). 9. Repeat Steps 7 and 8 as required to achieve steering relief pressure of 921 ± 10% psi (4 ± 10% bar). Could relief valve be adjusted to achieve 921 ± 10% psi (4 ± 10% bar)? YES Steering relief valve is good. Proceed to step 10. NO Repair or replace steering relief valve. See Steering Unit (PN ) on page 7- or Steering Unit (PN ) on page 7-13, then proceed to step Insert plastic plug. 11. Install steering unit and steering column. 12. Disconnect and remove test equipment. Install all hoses and fittings as noted prior to removal. 13. Install and connect all components as noted prior to test. 14. hydraulic oil level. Add oil as necessary. (Refer Parts and Maintenance Manual for correct oil spefications.) 1. Start engine. hydraulic system for leaks. Repair as necessary. 7 TN4343 Figure -8. Remove plastic plug (). 7. Using 8 mm Allen wrench (), adjust steering relief valve. Turning adjusting screw (7) clockwise increases pressure. Turning adjusting screw (7) counterclockwise decreases pressure. 8. Place steering unit and steering column in place and check steering relief pressure. (See Steering Relief Pressure Test on page -1.) Rev A -3

96 Repair Hydraulic Oil Tank Drain Procedure See Figure Park the mower safely. (See Park Mower Safely on page 1-.) 1 Installation Notes Connect hoses by reversing the order of removal. Replace hydraulic oil filter. (See Hydraulic Oil Filter on page -4.) Refill hydraulic tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary. Hydraulic Oil Filter Removal and Installation See Figure Park the mower safely. (See Park Mower Safely on page 1-.) 2. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) Figure -9 TN302 NOTES Label all hydraulic hoses and tubes before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination. The hydraulic oil tank capaty is gal (19 L). Use appropriate containers when draining hydraulic oil. 2. Place a suitable container under the hydraulic pump (3). 3. Loosen hose clamps (2) and disconnect hoses (4 and ) from hydraulic pump (3). 4. Loosen the hydraulic oil tank cap (1) to provide a vent for draining oil. NOTE 1 Figure -0 Use a suitable container to catch residual oil. 3. Remove hydraulic oil filter (1). TN Rev A

97 Installation Notes Install hydraulic oil filter by reversing the order of removal. Replace hydraulic oil filter. 3 4 Refill hydraulic tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary. 14 Hydraulic Oil Tank 13 7 Removal and Installation See Figures -1 and Park the mower safely. (See Park Mower Safely on page 1-.) Remove battery. (See Battery on page 4-4.) 3. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) 10 9 Figure -2 TN TN303 Figure Remove four screws (1) from tube flange (2). NOTES Fuel tank and support pan removed for picture clarity. Label all hydraulic hoses before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination.. Loosen four hose clamps (9) and remove hoses (10 and 11) from hydraulic oil tank (13).. Loosen nut (8) and screw (). 7. Remove nut (12). 8. Remove screw (3), washer (4), and band clamp (14). 9. Remove hydraulic oil tank (13). 10. Loosen hose clamp (7) and remove hose assembly () from hydraulic oil tank (13). Installation Notes Install hydraulic oil tank by reversing the order of removal. Replace hydraulic filter. (See Hydraulic Oil Filter on page -4.). Refill hydraulic oil tank. ((Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic oil tank for leaks and repair as necessary. hydraulic oil level and add if necessary Rev A -

98 Backlap NOTE The front backlap valves are shown. The center backlap valve is similar. Removal and Installation See Figure Park the mower safely. (See Park Mower Safely on page 1-.) 2. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) 3. Thoroughly clean the valve, espeally the area surrounding the hydraulic hoses, tubes, and fittings Installation Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Install the backlap valve by reversing the order of removal. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Tighten fittings (1 and 4) to 2 lb-ft (34 N m). Replace hydraulic oil filter. Refill hydraulic oil tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary. 3 Figure -3 TN340 NOTES Label all hydraulic hoses and tubes before disconnecting to aid in installation. Close all openings with caps or plugs to prevent contamination. 4. Disconnect hydraulic hoses (2 and 3) and remove backlap valve ().. Remove fittings (1 and 4) from backlap valve () Rev A

99 Load Control Removal and Installation See Figures -4 and Park the mower safely. (See Park Mower Safely on page 1-.) 2. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) 3. Thoroughly clean the valve, espeally the area surrounding the hydraulic hoses, tubes, and fittings. Installation Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Required Materials 3 4 Seal Kit (Jacobsen PN 4128) NOTES Figure -4 TN3499 Seat and top seat skirt removed for picture clarity. Label all hydraulic hoses and tubes before disconnecting to aid in installation. Record location and orientation of three tube clamps (12). Close all openings with caps or plugs to prevent contamination. 4. Disconnect hydraulic hoses (1, 7, and 9).. Remove fittings (2,, and 8) from load control valve (10).. Support the load control valve (10). 7. Remove two nuts (3), lock washers (4), and screws (). 8. Remove load control valve (10). 9. Remove load control cartridge (11) and inspect for wear or damage and replace as necessary. TN31 1 O-Ring 3 Ring O-Ring 2 Backup Ring 4 O-Ring Load Control Cartridge Figure -: Seal Kit (Jacobsen PN 4128) Install the load control valve by reversing the order of removal. Use new seal kit on load control cartridge during assembly. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings and seals prior to assembly. Tighten fittings (2,, and 8) to 17 lb-ft (23 N m). Replace hydraulic oil filter. Refill hydraulic oil tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary Rev A -7

100 Page Intentionally Blank Rev A

101 Control Removal and Installation See Figures - through Park the mower safely. (See Park Mower Safely on page 1-.) 2. Remove front cowling. (See Front Cowling on page 9-17.) 3. Drain hydraulic oil tank. (See Hydraulic Oil Tank Drain Procedure on page -4.) 4. Thoroughly clean the valve, espeally the area surrounding the hydraulic hoses, tubes, and fittings. 9 1 NOTES Figure - Label all hydraulic hoses and tubes before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination.. Disconnect hydraulic tubes (1 through 1) TN333 Figure Support the control valve (22). 8. Remove three screws (18), lock washers (19), lock washers (20), and nuts (21). 9. Remove control valve (22) TN333 Figure Remove fittings (23 through 37) from control valve (22) TN TN32 Figure -7. Remove five cotter pins (1) and clevis pins (17) Rev A -9

102 Installation Notes Install the control valve by reversing the order of removal. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Tighten ports A and B fittings (30 and 32) of section to 90 lb-ft (122 N m). Tighten port P1 fitting (23) of section to lb-ft (7 N m). Tighten port P2 fitting (24) of section to 2 lb-ft (34 N m). Tighten port P3 fitting (2) of section 4 to 2 lb-ft (34 N m). Tighten ports A and B fittings (27 29, and 33 3) of sections 3 to 48 lb-ft ( N m). Tighten ports A and B fittings (2 and 3) of section 2 to 2 lb-ft (34 N m). Tighten port P4 fitting (37) of section 1 to 2 lb-ft (34 N m). Tighten port T1 fitting (31) to 33 lb-ft. (4 N m). Replace hydraulic oil filter. (See Hydraulic Oil Filter on page -4.) Refill hydraulic tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary Rev A

103 Disassembly, Inspection, and Assembly See Figure Positioner 9 Pin Kit 1 4 Way Complete 23 Clevis (2) 2 Positioner Spool (4) 10 Dust Boot () 17 Relief Seal Kit (3) 24 4 Way FF 3 Shim (AR) 11 Spool Seal Kit () 18 Relief Assembly (3) 2 4 Way Complete 4 Viton O-Ring 12 Plug Seal Kit (7) 19 Midsection Seal Kit () 2 4 Way Complete Relief Seal Kit 13 Plug Assembly (2) 20 Right Cover Complete Plate 27 Main Relief Cartridge Cover Plate 14 Disc Seal (2) 21 Bolt 28 Washer Shim (AR) 7 Nut (3) 1 4 Way Complete 22 O-Ring Clevis (2) 29 Relief Kit 8 O-Ring Figure TN Rev A -1

104 Assembly Notes NOTICE It is important that all component parts are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. Required Materials Main Relief Cartridge Seal Kit (Jacobsen PN 2007) Spool Seal Kit (Jacobsen PN 41277) Plug Seal Kit (Jacobsen PN ) Relief Seal Kit (Jacobsen PN 4709) Midsection Seal Kit (Jacobsen PN 0132) Assemble the control valve by reversing the order of disassembly. Inspect all components for wear or damage and replace as necessary. Use a new main relief cartridge seal kit, spool seal kit, check plug seal kit, relief seal kit, and midsection seal kit during assembly. Lubricate all O-rings prior to assembly. Ensure disc seals (14) are installed between sections (1 and 1) and sections (1 and 2) during assembly. Rear Lift Cylinder NOTE The rear lift cylinders for the diesel and gasoline models are removed and installed the same way, except where noted. Removal and Installation See Figures -71 through -78.! CAUTION Care must be taken to avoid damaging the surface of the cylinder rod during removal and installation. 1. Lower cutting units. 2. Park the mower safely. (See Park Mower Safely on page 1-.) TN3318 Figure Remove screw (4), lock washer (), two large flat washers (3), spacer (1), and roller cam (2) Rev A

105 NOTES Figure -72 Label all hydraulic hoses and tubes before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination. 4. Disconnect hydraulic hose (7) from fitting (). TN Figure -74. Disconnect hydraulic hose (14) from fitting (10). 7. Remove cotter pin (11) and washer (12) from pin (13). 1 1 TN TN3434 Figure -73. Disconnect hydraulic hose (9) from fitting (8). 18 NOTE Figure -7 TN343 Diesel model shown; gasoline models are similar. 8. Support the rear lift cylinder (18). 9. Slide the pin (13) toward the rear of the machine, and remove spacer (1), washers (1 and 17), and lift cylinder (18) Rev A -3

106 19 18 NOTES Label all hydraulic hoses before disconnecting to ensure correct installation. Note the orientation of the fittings before removing to ensure correct installation. 11. Disconnect hose (7) from fitting (10). 12. Remove fitting (10) from lift cylinder (18). 13. Remove fitting (8) from lift cylinder (18) NOTE Figure -7 TN3479 Step 10 applies to gasoline models only. 10. Remove cotter pin (20) and remove pin (21) and two hanger plates (19) from lift cylinder (18) Figure -78 TN NOTE Count the number of turns required to remove the lift bracket, to ensure correct assembly. 14. Loosen the jam nut (22), and remove the lift bracket (23) from the lift cylinder (18). 18 Figure -77 TN Rev A

107 Installation Notes Install rear lift cylinder by reversing the order of removal. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Tighten fittings (8 and 10) to 2 lb-ft (34 N m). Tighten hoses (7, 9, and 14) to 2 lb-ft (34 N m). Lubricate grease fittings with grease that meets or exceeds NLGI Grade 2 LB spefications. Replace hydraulic oil filter. Refill hydraulic tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary. Adjust the rear lift cylinder. (See Rear Lift Cylinder Adjustment on page 8-19.) Disassembly, Inspection, and Assembly See Figures -79 through TN33 Figure Remove nut () from rod (3).. Remove piston (8).. Remove piston ring (), seal (7), and O-ring (9) from piston. 7. Remove spacer (10). 8. Remove rod guide (13). 9. Remove O-ring (11) and backup washer (12) TN331, TN332 Figure Secure end of rod (3). 2. Compress snap ring (2) and carefully tap edge of cylinder barrel (1) with a soft-face hammer to disengage rod assembly (4) from cylinder barrel. 3. Pull rod assembly (4) out of cylinder barrel (1). TN334 Figure Remove snap ring (2). 11. Remove wiper (1). 12. Remove O-ring (14) and rod seal (1) assembly Rev A -

108 Assembly Notes 14 1 Required Materials Seal Kit (Jacobsen P/N ) Assemble the rear lift cylinder by reversing the order of disassembly. Lubricate all parts with clean hydraulic oil before assembly. Install new seals and O-rings. Ensure new O-rings are in place before installing fittings. Figure Remove O-ring (14) from rod seal (1). TN33! WARNING Use appropriate eye protection when using compressed air for cleaning or drying purposes. Compressed air can cause serious personal injury. Use safety reduction valves to reduce the air pressure to a safe level before use. NOTICE It is important that all components are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. 14. Clean all parts using clean solvent, and dry using compressed air. 1. Inspect all parts for excessive wear, cracks, broken parts, and damaged threads, and repair or replace as necessary. 1. Inspect the barrel for dents, score lines, or grooves inside, and repair or replace as necessary. 17. Inspect the fittings for wear and damage, and repair or replace as necessary Rev A

109 Front Lift Cylinder Removal and Installation See Figures -83 through ! CAUTION Care must be taken to avoid damaging the surface of the cylinder rod during removal and installation Lower cutting units. 2. Park the mower safely. (See Park Mower Safely on page 1-.) 3. Remove front cutting units. (See Front Cutting Units on page 8-23.) Figure -84. Support the front lift cylinder (3). 7. Remove cotter pin (9), cylinder mounting pin (11), and washer (8), and lower the piston end of the front lift cylinder from the frame bracket (10). 8. Remove snap ring (4), and remove the rod end of the front lift cylinder (3) from left lift lever (). NOTES 8 Note the orientation of the thrust washer and the location and number of washers used before removing to ensure correct installation. 9. Remove thrust washer () and washers (7) from left lift lever (). 7 TN331 Figure -83 TN NOTES Label all hydraulic hoses before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination. 4. Raise and support front of machine with jackstands.. Disconnect hydraulic hoses (1 and 2). 14 Figure -8 1 TN337 NOTES Label all hydraulic hoses before disconnecting to ensure correct installation. Close all openings with caps or plugs to prevent contamination. 10. Disconnect hoses (12 and 13). 11. Loosen jam nut (14) and remove rod end (1) Rev A -7

110 Installation Notes Install front lift cylinder by reversing the order of removal. Ensure new O-rings are in place before installing fittings. Lubricate all O-rings prior to assembly. Tighten hoses (1, 2, 12, and 13) to 2 lb-ft (34 N m). Lubricate grease fittings with grease that meets or exceeds NLGI Grade 2 LB spefications. Replace hydraulic filter. (See Hydraulic Oil Filter on page -4.) Refill hydraulic tank. (Refer to Parts and Maintenance Manual for correct oil spefications.) Start engine. hydraulic system for leaks. Repair as necessary. hydraulic oil level and add if necessary. Adjust front lift cylinder. (See Front Lift Cylinder Adjustment on page 8-18.) Disassembly, Inspection, and Assembly See Figures -8 through TN333 Figure Remove nut () from rod (3).. Remove piston (8).. Remove piston ring (), seal (7), and O-ring (9) from piston. 7. Remove rod guide (12). 8. Remove O-ring (10) and backup washer (11) TN331, TN332 Figure Secure end of rod (3). 2. Compress snap ring (2) and carefully tap edge of cylinder barrel (1) with a soft face hammer to disengage rod assembly (4) from cylinder barrel. 3. Pull rod assembly (4) out of cylinder barrel (1). TN334 Figure Remove snap ring (2). 10. Remove wiper (1). 11. Remove O-ring (13) and rod seal (14) assembly Rev A

111 Assembly Notes Required Materials Seal Kit (Jacobsen P/N ) Assemble the front lift cylinder by reversing the order of disassembly. Lubricate all parts with clean hydraulic oil before assembly. Install new seals and O-rings. Figure Remove O-ring (13) from rod seal (14). TN33! WARNING Use appropriate eye protection when using compressed air for cleaning or drying purposes. Compressed air can cause serious personal injury. Use safety reduction valves to reduce the air pressure to a safe level before use. NOTICE It is important that all components are absolutely clean, as contamination can result in serious damage and/or improper operation. Never use shop towels or rags to dry parts after cleaning, as lint may clog passages. Dry parts using compressed air. 13. Clean all parts using clean solvent, and dry using compressed air. 14. Inspect all parts for excessive wear, cracks, broken parts, and damaged threads, and repair or replace as necessary. 1. Inspect the barrel for dents, score lines, or grooves inside, and repair or replace as necessary. 1. Inspect the fittings for wear and damage, and repair or replace as necessary Rev A -9