8-1 GENERAL...8-2 SPECIFICATIONS...8-6 COMPONENTS...8-7 FRONT BRAKE...8-12 DISASSEMBLY INSPECTION REASSEMBLY (Pn1, Cu2 3 TON SERIES)...8-12 DISASSEMBLY INSPECTION REASSEMBLY (Pn2 3 TON SERIES)...8-17 BRAKE AIR BLEEDING...8-22 BRAKING FORCE INSPECTION ADJUSTMENT...8-22 BRAKE MASTER CYLINDER...8-23 REMOVAL INSTALLATION...8-23 DISASSEMBLY INSPECTION REASSEMBLY...8-24 PARKING BRAKE INSPECTION ADJUSTMENT...8-26 RELEASE LEVER CABLE ADJUSTMENT...8-26 BRAKE PEDAL INSPECTION ADJUSTMENT...8-27 INCHING PEDAL INSPECTION ADJUSTMENT...8-28 SINGLE BRAKE (INCHING) PEDAL INSPECTION ADJUSTMENT (1-PEDAL: OPT)...8-29 WET BRAKE...8-30 GENERAL...8-30 SPECIFICATIONS...8-33 HYDRAULIC CIRCUIT DIAGRAM...8-34 COMPONENTS...8-35 FRONT BRAKE ASSY...8-39 BRAKE Page DEPRESSURIZING THE ACCUMULATOR...8-45 PURGING THE AIR FROM THE BRAKE...8-45 BRAKING POWER INSPECTION...8-45 POINTS FOR LOCKING THE BRAKE DISK - PLATE NO. 1 - PLATE NO. 2...8-46 ADJUSTING THE BRAKE DISK GAP...8-47 BRAKE VALVE...8-48 BRAKE VALVE OPERATION INSPECTION...8-51 ACCUMULATOR ASSY...8-52 ACCUMULATOR INSPECTION...8-54 PARKING BRAKE ASSY...8-55 PARKING BRAKE FUNCTION INSPECTION...8-58 ADJUSTING THE PARKING LEVER SWITCH...8-58 PARKING BRAKE INSPECTION AND ADJUSTMENT...8-59 ADJUSTING THE RELEASE LEVER CABLE...8-59 BRAKE COOLING OIL TANK...8-60 PROCEDURE FOR POURING IN BRAKE COOLING OIL...8-61 BRAKE COOLING OIL COOLER...8-62 BRAKE PEDAL INSPECTION AND ADJUSTMENT...8-63 INCHING PEDAL INSPECTION AND ADJUSTMENT...8-64 INSPECTION AND ADJUSTMENT OF THE SINGLE BRAKE (INCHING) PEDAL...8-65 GREASING TO PARKING BRAKE PEDAL RELEASE PIN...8-66 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 E
8-2 GENERAL FRONT BRAKE Pn1 ton series Wheel Cylinder
8-3 Pn2 3 ton series Wheel Cylinder 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 E
8-4 Cu2 3 ton Series Wheel Cylinder
8-5 Parking 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 E
8-6 Master Cylinder SPECIFICATIONS 8FGCU15,18,SU20
8-7 COMPONENTS FRONT BRAKE Pn1 ton series 4715 Pn2 3 ton series 4715
8-8 Cu2 3 ton series 4715 pipe 4714
8-9 BRAKE MASTER CYLINDER 4702 4702
8-10 PARKING BRAKE 4601
8-11 BRAKE PEDAL 4701 SINGLE BRAKE PEDAL 4701
8-12 FRONT BRAKE DISASSEMBLY INSPECTION REASSEMBLY (Pn1, Cu2 3 TON SERIES) T = N m (kgf cm) [ft lbf] Pn1 ton series T = 7.8 ~ 11.8 (80 ~ 120) [5.8 ~ 8.68] Cu2 3 ton series T = 17.7 ~ 26.5 (180 ~ 270) [13.0 ~ 19.5] 11 4 5 12 9 8 3 6 7 backing plate set bolt T = 137 ~ 210 (1400 ~ 2100) [101.3 ~ 154.9] Disassembly Procedure 1 Drain brake fluid. 2 Remove the front axle hub. (See page 7-8) [Point 1] 3 Remove the shoe hold down spring and cup. [Point 2] 4 Remove the anchor to shoe spring and shoe guide plate. [Point 3] 5 Remove the cable and cable guide. 6 Remove the lever strut. [Point 4] 7 Remove the adjuster spring and adjusting screw. [Point 5] 8 Disconnect the parking brake cable. [Point 6] 9 Remove the brake shoe. [Point 7] 10 Disconnect the brake pipe. 11 Remove the wheel cylinder ASSY. [Point 8] 12 Remove the backing plate. [Point 9]
8-13 Reassembly Procedure The reassembly procedure is the reverse of the disassembly procedure. Note: Check that the brake lining and brake drum interior surface are free from grease or oil before installation. Before reassembly, decrease the brake drum outside diameter to approx. 1 mm (0.04 in) less than the drum inside diameter by tightening the adjusting screw. After reassembly, perform brake air bleeding (see page 8-22) and braking force inspection (see page 8-22). Apply thread tightener (08833-76001-71 (08833-00070)) to the backing plate set bolt before reassembly. Point Operations [Point 1] Inspection: Measure the brake drum inside diameter. Standard Pn1 ton series: 254 mm (10.0 in) Cu2 3 ton series: 310 mm (12.20 in) Limit Pn1 ton series: 256 mm (10.1 in) Cu2 3 ton series: 312 mm (12.28 in) Apply thread tightener (08833-76001-71 (08833-00070)) on the brake drum set nut before reassembly. [Point 2] Disassembly SST 09510-31960-71 SST Inspection: Measure the free length of the hold down spring. Standard: 25.5 mm (1.004 in)
8-14 Apply liquid packing (08826-76002-71 (08826-00090)) to the shoe hold down pin and the contact surface on the back side of the backing plate to eliminate any clearance. [Point 3] Disassembly: SST 09717-76001-71 (09717-20010) SST Inspection: Measure the free length of the anchor to shoe spring. Standard Pn1 ton series: 102.2 mm (4.024 in) Cu2 3 ton series: On the side of lining W/ pin 139.3 mm (5.484 in) On the side of lining L/ pin 121.8 mm (4.795 in) Limit: No clearance between coil turns SST SST 09718-76001-71 (09718-20010) [Point 4] Inspection: Measure the free length of the strut to shoe spring. Standard Pn1 ton series: 19.7 mm (0.776 in) Cu2 3 ton series: 29.8 mm (1.173 in)
8-15 [Point 5] Inspection: Measure the free length of the adjuster spring. Standard Pn1 ton series: 99.4 mm (3.913 in) Cu2 3 ton series: 126.0 mm (4.961 in) Limit: No clearance between coil turns Apply grease to the adjusting screw threaded portion and fill grease in the cap. Tie a wire to the free end of the adjuster spring and set it by pulling the wire with a screwdriver. [Point 6] Apply liquid packing (08826-76002-71 (08826-00090)) to the parking brake cable outlet of the backing plate to eliminate any clearance. [Point 7] Inspection: Measure the brake lining thickness. Standard Pn1 ton series: 4.9 mm (0.193 in) Cu2 3 ton series: 5.7 mm (0.224 in) Limit Pn1 ton series: 1.0 mm (0.039 in) Cu2 3 ton series: 1.0 mm (0.039 in) Before brake shoe installation, apply grease to the portions of the backing plate shown in the illustration (6 places in contact with the shoe rim and the anchor pin).
8-16 [Point 8] Inspection: Measure the clearance between the wheel cylinder and piston. Limit Pn1 ton series: 0.125 mm (0.00492 in) Cu2 3 ton series: 0.15 mm (0.0059 in) Apply liquid packing (08826-76002-71 (08826-00090)) to the backing plate fitting portion of the wheel cylinder and on the whole periphery of the set bolts to eliminate any clearance. Pn1 ton series Cu2 3 ton series [Point 9] Carefully install the backing plate set bolts because they are different in length. Apply thread tightener (08833-76001-71 (08833-00070)) on the set bolts before reassembly. Bolt length B: l = 40 mm (1.57 in) Apply liquid packing (08826-76002-71 (08826-00090)) to the contact surface between the backing plate and front axle bracket shown in the illustration to eliminate any clearance.
8-17 DISASSEMBLY INSPECTION REASSEMBLY (Pn2 3 TON SERIES) T = N m (kgf cm) [ft lbf] 3 13 12 10 6 4 7 9 5 3 3 8 Wheel cylinder set bolt T = 14.7 ~ 19.6 (150 ~ 200) [10.9 ~ 14.5] backing plate set bolt T = 137 ~ 210 (1400 ~ 2100) [101.3 ~ 154.9] Disassembly Procedure 1 Drain brake fluid. 2 Remove the front axle hub. (See page 7-8.) [Point 1] 3 Remove the hold down spring. [Point 2] 4 Remove the pawl lever stopper. [Point 3] 5 Remove the pawl lever. 6 Remove the anchor to shoe spring. [Point 4] 7 Remove the strut lever. [Point 5] 8 Remove the adjuster spring and adjusting screw. [Point 6] 9 Disconnect the parking brake cable. [Point 7] 10 Remove the brake shoe. [Point 8] 11 Disconnect the brake piping. 12 Remove the wheel cylinder ASSY. [Point 9] 13 Remove the backing plate. [Point 10]
8-18 Reassembly Procedure The reassembly procedure is the reverse of the disassembly procedure. (With regard to steps 3 and 4, however, install the pawl lever stopper after installing the hold down spring.) Note: Check that the brake lining and brake drum interior surface are free from grease or oil before reassembly. Before reassembly, decrease the brake shoe outside diameter to approx. 1 mm (0.04 in) less than the brake drum inside diameter by tightening the adjusting screw. After reassembly, perform brake air bleeding (see page 8-22) and braking force inspection and adjustment (see page 8-22). Point Operations [Point 1] Inspection: Measure the brake drum inside diameter. Standard: 310 mm (12.20 in) Limit: 312 mm (12.28 in) Apply thread tightener (08833-76001-71 (08833-00070)) to the brake drum set nut before reassembly. SST [Point 2] Disassembly SST 09510-31960-71 Inspection: Measure the free length of the hold down spring. Standard: 34.5 mm (1.358 in) Limit: 31.3 mm (1.232 in) Apply liquid packing (08826-76002-71 (08826-00090)) to the back side of the backing plate in contact with the shoe hold down spring to eliminate any clearance.
8-19 [Point 3] Inspection: Measure the free length of the actuator spring. Standard: 124.5 mm (4.902 in) Limit: No clearance between coil turns Use snap ring pliers to install the pawl lever stopper and actuator spring. [Point 4] Disassembly: SST 09717-76001-71 (09717-20010) SST Inspection: Measure the free length of the anchor to shoe spring. Standard: 106 mm (4.17 in) Limit: No clearance between coil turns SST SST 09718-76001-71 (09718-20010)
8-20 [Point 5] Inspection: Measure the free length of the strut to shoe spring. Standard: 23 mm (0.91 in) Limit: 20 mm (0.79 in) [Point 6] Inspection: Measure the free length of the adjuster spring. Standard: 86 mm (3.39 in) Limit: No clearance between coil turns Apply grease to the adjusting screw threaded portion and fill grease in the cap. [Point 7] Apply liquid packing (08826-76002-71 (08826-00090)) to the parking brake outlet of the backing plate to eliminate any clearance. [Point 8] Inspection: Measure the brake lining thickness. Standard: 7.0 mm (0.276 in) Limit: 2.0 mm (0.079 in)
8-21 Apply grease to the portions of the backing plate shown in the illustration (6 places in contact with the shoe rim and the anchor pin) before brake shoe installation. [Point 9] Inspection: Measure the clearance between the wheel cylinder and piston. Limit: 0.145 mm (0.00571 in) Apply liquid packing (08826-76002-71 (08826-00090)) to the wheel cylinder backing plate fitting portion and the whole periphery of set bolts to eliminate any clearance. Pn2 ton series Pn3 ton series [Point 10] Carefully install the backing plate set bolts in the correct positions since they are different in length. Apply thread tightener (08833-76001-71 (08833-00070)) to the set bolts before reassembly. Bolt length A: l = 36 mm (1.42 in) B: l = 40 mm (1.57 in) C: l = 45 mm (1.77 in) Apply liquid packing (08826-76002-71 (08826-00090)) to the contact surface between the backing plate and front axle bracket shown in the illustration to eliminate any clearance.
8-22 Inching cable Single brake pedal spec. Inching lever BRAKE AIR BLEEDING Note: Add brake fluid to the reservoir tank during air bleeding to prevent it from becoming insufficient. When the pedal needs to be pushed all the way for air bleeding, torque converter inching cable shall be disconnect from torque converter at inching lever. (single brake pedal spec.) 1. Bleed air from the brake master cylinder. (1) Depress the brake pedal several times to compress the air in the piping, and hold that state. (2) Loosen the bleeder plug to discharge air in the piping with the brake fluid, and tighten the plug immediately before the fluid stops coming out. (3) Repeat steps (1) and (2) above until no air bubbles are seen in the discharged brake fluid. 2. Bleed air from wheel cylinders RH and LH. (1) Operate as described in step 1 above for the RH and LH side at a time. 3. Add brake fluid to the specified level. (1) Add brake fluid through the filter provided in the reservoir tank. (2) Add brake fluid up to the specified level in the reservoir tank. BRAKING FORCE INSPECTION ADJUSTMENT 1. Inspect the braking force using a brake tester or by traveling test. Braking distance (without load) Initial speed of braking km/h (mph) Max. speed Braking distance m (ft) 5.0 (16.4) or less 2. Adjust the braking force. (1) Repeat traveling in the forward and reverse directions to adjust the brake shoe clearance. The adjusting screw adjusts the clearance automatically when the brake pedal is depressed in reverse traveling. (2) If the braking force is insufficient, adjuster malfunction, lining contact defect, foreign matter adhesion on the lining or brake fluid leakage is assumed. Remove and inspect the brake drum. (3) When the brake shoe is replaced with a new one, repeat traveling in the forward and reverse directions for running in.
8-23 BRAKE MASTER CYLINDER REMOVAL INSTALLATION T = N m (kgf cm) [ft lbf] 7 T=6.8~15.8 (69~161) [5.0~11.7] 6 7 6 8 LBC47-001 Removal Procedure 1 Remove the lower panel. 2 Remove the toe board. 3 Remove the instrument panel. 4 Remove the column cover. 5 Disconnect the brake side hose from the reservoir tank and drain brake fluid. 6 Disconnect the piping. 7 Remove the push rod clevis pin. 8 Remove the brake master cylinder. Installation Procedure The installation procedure is the reverse of the removal procedure. Note: After installation, perform brake pedal adjustment (see page 8-27) and air bleeding (see page 8-22).
8-24 DISASSEMBLY INSPECTION REASSEMBLY 5 1 4 4 2 3 5 Disassembly Procedure 1 Turn the boot up and remove the snap ring. 2 Remove the push rod. [Point 1] 3 Remove the piston. [Point 2] 4 Remove the pin and the fluid inlet elbow. 5 Remove the outlet plug and valve. Reassembly Procedure The reassembly procedure is the reverse of the disassembly procedure.
8-25 Point Operations [Point 1] Temporarily set the push rod length to the illustrated dimension, and make readjustment after installation. 130 mm (5.118 in) [Point 2] Apply rubber grease to the piston cup and whole periphery of the cup before reassembly.
8-26 A PARKING BRAKE INSPECTION ADJUSTMENT 1. Check the parking brake cable set position. Standard: A = 0 ~ 2 mm (0 ~ 0.08 in) 2. Apply chassis grease to the portions indicated by arrows. LH When using the SST RH (A) 3. Inspect and adjust the parking brake pedal operating force. (1) Set the SST to the parking brake pedal. SST 09460-26600-71 (2) Set a spring scale to the SST and pull it backward to measure the operating force. SST When not using the SST (B) Standard: (A) When using the SST 112 ~ 136 N (11.4 ~ 13.9 kgf) [25.1 ~ 30.6 lbf] (B) When not using the SST 186 ~ 226 N (19 ~ 23 kgf) [42 ~ 51 lbf] (3) If the operating force is out of the standard range, release the parking brake and make adjustment at the adjusting portion. Clockwise turn: Increases the operating force. Counterclockwise turn: Decreases the operating force. RELEASE LEVER CABLE ADJUSTMENT 1. Adjust the play of the release lever to 0 to 5 mm (0 to 0.2 in) at the tip of the lever using the release cable adjusting nut. Adjusting nut Release lever
8-27 BRAKE PEDAL INSPECTION ADJUSTMENT Stop lamp switch master cylinder C A Reference value 135 ~ 140 mm (5.315 ~ 5.512 in) D (11.0 mm (0.433 in)) Push rod B Toe board Floor mat 1. Inspect brake pedal height A. (From toe board to top of pedal) Standard: A = 145 ~ 150 mm (5.91 ~ 6.10 in) (with pedal pad) If the standard is not satisfied, make adjustment by changing the stop lamp switch position. 2. Inspect brake pedal play B. Standard: B = 1 ~ 5 mm (0.039 ~ 0.197 in) If the standard is not satisfied, make adjustment by changing the master cylinder push rod length. 3. Check master cylinder push rod play C with the brake pedal in the above state. Standard: C = 1 mm (0.04 in) 4. After the adjustment, fully depress the brake pedal and inspect pedal height D. Standard: D = 90 mm (3.54 in) or more
8-28 INCHING PEDAL INSPECTION ADJUSTMENT pedal link Stopper bolt Inching pedal plate Adjusting nut B A C Floor mat (135 ~ 140 mm (5.315 ~ 5.512 in)) (145 ~ 150 mm (5.709 ~ 5.906 in)) Toe board Adjusting nut Inching lever 1. Inspect and adjust the brake pedal height and play (See page 8-27). 2. Inspect stroke A of the inching pedal until interlocking with the brake (pedal stroke until the inching pedal plate comes into contact with the brake link). Standard Pn1 ton series: A = 35 ~ 41 mm (1.38 ~ 1.61 in) Others: A = 26 ~ 32 mm (1.02 ~ 1.26 in) If the standard is not satisfied, adjust the stopper bolt protrusion. Adjust the brake pedal height within + 15 mm (0.59 in). 3. Inspect and adjust the inching cable. (1) Inspect inching cable length B on the pedal side. Standard: B = 17.5 mm (0.689 in) If the standard is not satisfied, adjust it by turning the adjusting nuts on the pedal side. (2) Inspect inching pedal play C before the inching lever starts to move. Standard: C = 1 ~ 3 mm (0.04 ~ 0.12 in) If the standard is not satisfied, adjust it by turning the adjusting nuts on the inching lever side.
8-29 SINGLE BRAKE (INCHING) PEDAL INSPECTION ADJUSTMENT (1-PEDAL: OPT) Adjusting bolt Stopper bolt Inching pedal No gap (a) pedal plate link Push rod Adjusting nut B A C Floor mat 130 ~ 135 mm (5.118 ~ 5.315 in) 140 ~ 145 mm (5.512 ~ 5.709 in) 11 mm (0.433 in) Toe board Adjusting nut Inching lever 1 Tighten the adjusting bolt until there is no gap between the adjusting bolt and surface (a) of the inching pedal, and tighten the lock nut. 2 Adjust the height and play of the pedal. The values specified in the above illustration should be used as the standard for the pedal height. Refer to page 8-27 for adjustment method. 3. Inspect stroke A of the pedal until interlocking with the brake (pedal stroke until the pedal plate and bolt head comes into contact with the brake link). Standard Pn1 ton series: A = 41.7 ~ 48.7 mm (1.64 ~ 1.92 in) Others: A = 29.7 ~ 36.7 mm (1.17 ~ 1.44 in) If the standard is not satisfied, adjust the stop lamp switch or stopper bolt protrusion. 4. Inspect and adjust the inching cable. (1) Inspect the inching cable length B on the pedal side. Standard: B = 17.5 mm (0.689 in) If the standard is not satisfied, make adjustment by turning the adjusting nuts on the pedal side. (2) Inspect inching pedal play C until the torque converter inching lever starts to move. Standard: C = 1 ~ 3 mm (0.04 ~ 0.12 in) LBC47-002 If the standard is not satisfied, make adjustment by turning the adjusting nuts on the torque converter side.
8-30 WET BRAKE GENERAL Front A A A-A
8-31 Parking Pn2, Cu2, Cu3 ton series Pn3 ton series Accumulator WARNING: It contains nitrogen under high pressure. Don t allow fire or heat near it. Don t try to disassemble it. Wear eye protection and carefully drill a hole at the point marked to release GAS pressure before disposal.
8-32 Flow Divider Valve (for Cooling System) Check Valve Relief Valve IN OUT
8-33 Valve From accumulator To front brake From oil pump To oil tank Pressure testing opening To PS valve SPECIFICATIONS Item Foot brake Parking brake valve Type lining dimensions (Thickness x Outside diameter x Inside diameter) Model mm (in) Pn2 series Pn3 series Cu2 series Cu3 series Wet disc brake 2.0 x 260 x 198 (0.08 x 10.24 x 7.80) Number of discs 5 discs 6 discs 4 discs 5 discs Type Mechanical disc brake lining dimensions (Thickness x Outside diameter x Inside diameter) Number of discs Type mm (in) 1.6 x 112 x 84 (0.06 x 4.41 x 3.31) 7 disc Full power CHPS Input piston outside diameter mm (in) 25.4 (1.0) Input piston stroke mm (in) 12.7 (0.5) Maximum hydraulic pressure Mpa (kgf/cm 2 ) 7.8 (79.5) [1131] Oil used Hydraulic oil ISO VG32 Cooling oil SHELL DONAX TD Cooling oil capacity I (USgal) 7.8 ~ 8.2 (2.1 ~ 2.2) 7.2 ~ 7.6 (1.9 ~ 2.0)
8-34 HYDRAULIC CIRCUIT DIAGRAM operation system PS valve valve Flow divider valve Oil control valve Wet brake Orifice Check valve Oil tank Relief valve Accumulator Warning buzzer & lamp cooling system Relief valve Flow divider valve cooling oil tank Wet brake LH Oil cooler Engine Torque converter & transmission Front axle Oil pump Relief valve Wet brake RH
8-35 COMPONENTS Parking 4601 Pedal 4701
8-36 Valve 4704 Accumulator 4706
8-37 Piping 4714 4714
8-38 Cheak Valve 4714 ASSY 4715
8-39 FRONT BRAKE ASSY DISASSEMBLY INSPECTION REASSEMBLY Note: Depressurize the accumulator before starting the operation (Refer to 8-46) T = N m (kgf cm) [ft lbf] Pn2 3 T = 137 ~ 210 (1400 ~ 2100) [101 ~ 155] Cu2 3 T = 90 ~ 120 (900 ~ 1200) [66 ~ 89] 3 2 T = 44.1 ~ 59.8 (450 ~ 610) [32.5 ~ 44.1] 6 4 9 8 5 7 10 Disassembly Procedure 1 Remove the front axle hab. (see page XX-XX) 2 Remove the bushing. (except for Cu2 ton series) [Point 1] 3 Remove the ASSY. [Point 2] 4 Remove the inner housing. [Point 3] 5 Remove the plate No.2 and the spring. [Point 4] 6 Remove the plate No.1 and the brake disk [Point 5] 7 Remove the snap ring and oil seal. 8 Remove the piston and piston seal. [Point 6] 9 Remove the pressure plate and steel balls. [Point 7] 10 Remove the cam, lever, adjusting bolt and O-ring. Reassembly Procedure The reassembly procedure is reverse of the disassembly procedure.
8-40 Note: After reassembly, perform brake air bleeding. (see page 8-46) After reassembling, check the operation of the accumulator. (see page 8-55) During reassembling, check that no foreign matter is attached to the parts. SST (2) Point Operations [Point 1] Removal: SST 09950-76018-71... (1) (09950-60010) 09950-76014-71... (2) (09950-40011) SST (1) Except Cu3 ton series A Cu3 ton series Installation: Use a copper bar to reassemble the bushing into the position A in the drawing. Standard Except Cu3 ton series: A = 0 ~ 1 mm (0 ~ 0.039 in) Cu3 ton series: Press the bush in until it contacts the axel housing. Pn2 Pn3 ton series Cu2 Cu3 ton series [Point 2] Apply a sealant (08826-76002-71 (08826-00090)) to the contact surface of the brake assembly and front axel bracket, and reassemble them. Pn2 3 ton series Check the brake cooling oil hole, and assemble the O ring between the brake assembly and front axel bracket. Cu2 3 ton series Cooling oil hole
8-41 [Point 3] Reassemble the brake assembly in the following procedure. 1. Raise the housing by placing wooden blocks under the outer housing, taking care not to press on the oil seal. 2. Place the brake discs and plates No.1 alternately in the housing. 3. Reassemble the springs (6 pieces). 4. Align the plate No. 2 with the groove in the outer housing. 5. Hand tighten the housing set bolt and nut, and set the inner housing so that it floats up by the power of the springs. 6. Press the inner housing by hand to check that it seals. If it cannot be pressed to seal by hand, then plate No. 2 is not in the correct position. Carry out step 4 again. 7. Reassemble the housing set bolt and nut to the standard tightening torque. SST Use the SST to arrange the engagement of the gears of the brake disc, plate No. 1, and plate No. 2. SST 09472-26600-71 After engaging the gears, tighten the adjusting bolt to fix the disc. [Point 4] Inspection: Measure the thickness of plate No. 2. Standard: 3.6 mm (0.142 in) Limit: XX mm (XX in)
8-42 Inspection: Measure the free length of the spring. Standard: 25.7 mm (1.012 in) Limit: 23.7 mm (0.933 in) [Point 5] Inspection: Measure the thickness of plate No. 1. Standard: 2.0 mm (0.079 in) Limit: 1.7 mm (0.067 in) Inspection: Measure the thickness of the brake disc. Standard: 35 mm (0.138 in) Limit: 3.2 mm (0.126 in)
8-43 Service tab [Point 6] Disassembly: When removing the brake piston, remove it using the 2 service tabs (M6 x 1.0). Piston seal Reassemble the brake piston in the following procedure. 1. After applying hydraulic oil to the piston seal, reassemble it to the housing by hand. Use gloves at this time. Piston seal 2. Prepare 3 box wrenches of equal height as a holder on which to place the housing. 3. Set the 3 box wrenches in contact with the flat face in the center of the housing, and set on a hand press. 4. Apply hydraulic oil to the contact surface of the piston seal by hand. Use gloves at this time.
8-44 5. Place the piston on the insertion face, and place a round plate or strong metal plate such as is shown in the drawing on top of the piston. Use a hand press to slowly insert the piston. When the operation of the hand press becomes heavy, stop the operation. Pressure plate [Point 7] When reassembling the pressure plate, check that the steel balls (3 balls) are assembled in the grooves of the inner housing and pressure plate before inserting the pressure plate. Steel ball
8-45 DEPRESSURIZING THE ACCUMULATOR 1. With the engine stopped. Depress the brake pedal fully to its stroke end. Depress it 100 times or more. BRAKING POWER INSPECTION 1. Inspect the braking power using a brake tester or by a driving test. Braking stop distance (in unloaded condition) Braking initial speed Maximum speed Stopping distance 5.0 m (196.9 in) or less PURGING THE AIR FROM THE BRAKE 2. When the braking power is insufficient, carry out the following inspections. Purge the air from the brake assembly in the following procedure. 1. Loosen the air purging breather plug on the brake assembly on one side. 2. Connect an air purging hose to the loosened breather plug. 3. Start the engine, and depress the brake pedal. (Until air stops coming out from the air purging hose) 4. Tighten the breather plug, and remove the air purging hose. Tightening torque: 7.0 ~ 12.0 N m (71.4 ~ 122.4 kgf cm) [5.2 ~ 8.9 ft lbf] 5. Carry out the operations 1-4 above for the brake assembly on the other side. (1) piping oil leakage inspection. (2) valve operation inspection. (3) If the brake disk is replace with a new part, drive forward and backward repeatedly to break the new disk in.
8-46 Bolt B Lock nut Bolt A Bolt A POINTS FOR LOCKING THE BRAKE DISK - PLATE NO. 1 - PLATE NO. 2 Note: When detaching the front axel hub, the brake disk can be temporarily locked so that the brake disk serrations do not slip out of alignment. The brake disk - plate No.1 - and plate No.2 are locked in the following procedure. 1. Loosen bolt A. 2. Loosen the lock nut. 3. Tighten bolt B until the adjusting lever comes into contact with the disk plate. At this point, make a note of the number of turns taken to tighten the bolt B. 4. Temporarily tighten bolt A. 5. To unlock the brake disc, reverse this procedure. Note: When the tightening dimension of the bolt B in point 3, is not clear, or when bolt A is close to the end of the long hole in the lever when bolt B is tightened, the disk may be worn. Adjust the brake disk gap. (Refer to page 8-48)
8-47 ADJUSTING THE BRAKE DISK GAP Note: Wear of the brake disk causes an increase in the brake piston stroke that affects the life of the brake. Therefore, the brake disk clearance should be adjusted every year (once a year (once every 2000H)). SST Union 1. Remove the lower panel and toe board. 2. Remove the plug in the pressure testing opening of the brake valve, attach the union there, then attach an oil pressure meter via the SST. Union 47711-21320-71 SST 09472-22000-71 3. With the engine stopped, depress the brake pedal and hold it in the position at which the oil pressure reaches the value below. Hold it in position either by having somebody step on it, or by fixing it in place with rope etc. Pedal holding standard pressure: 1.0 MPa (10 kgf/cm 2 ) [140 psi] Bolt B Lock nut X Bolt A 4. Loosen the adjusting lever set bolt A, tighten the bolt B until the adjusting lever comes into contact with the disk plate, then tighten the bolt A temporarily. 5. In the status described in 3., adjust the bolt B until the clearance X between the tip of bolt B and the adjusting lever equals the value below, then fix bolt B with the lock nut. Clearance X = 2.47 ~ 2.73 mm (0.097 ~ 0.107 in) Note: A clearance of X = 2.6 mm (0.102 in) corresponds to a brake disk clearance of 0.5 mm (0.020 in). 6. Loosen the temporarily tightened bolt A, check that the adjusting lever makes contact with the bolt B, then tighten the bolt A to the correct torque. Tightening torque for bolt A T = 13.7 ~ 22.6 N m (139.7 ~ 230.5 kgf cm) [10.1 ~ 16.7 ft lbf]
8-48 BRAKE VALVE REMOVAL INSTALLATION Note: Depressurize the accumulator before starting the operation (Refer to page 8-46) T = N m (kgf cm) [ft lbf] T = (~) [~] 5 7 6 5 6 T = 6.8~15.8 (69~161) [5.0~11.7] 8 Removal Procedure 1 Remove the lower panel. 2 Remove the toe board. 3 Remove the instrument panel. 4 Remove the column cover. 5 Disconnect the piping. 6 Remove the clevis pin of the push rod. 7 Remove the brake valve W/bracket. 8 Remove the bracket. Installation Procedure The installation procedure is the reverse of the removal procedure. Note: After installing, adjust the brake pedal (Refer to page 8-65) and purge the air (Refer to page 8-46). After installing check the operation of the accumulator. (Refer to page 8-55)
8-49 DISASSEMBLY INSPECTION REASSEMBLY Note: All components are machined to a high-precision finish. Be careful not to damage them while working. Conduct the work in a clean location. T = N m (kgf cm) [ft lbf] 3 T = 49.0 ~ 78.5 (500 ~ 800) [36.2 ~ 57.9] 1 2 4 6 9 10 8 T = 67.7 ~ 107.9 (690 ~ 1100) [49.9 ~ 79.6] 7 Disassembly Procedure 1 Remove the push rod. 2 Remove the boots. 3 Remove the lock nut, snap ring, and plate washer. [Point 1] 4 Remove the input piston and compression spring. [Point 2] 5 Remove the cylinder cap from the input piston. [Point 3] 6 Remove the hole plug. 7 Remove the closed valve, valve return spring, and spring retainer. [Point 4] 8 Remove the reaction piston guide W/reaction piston and the brake valve spool. 9 Remove the reaction piston guide. 10 Remove the reaction piston. Reasssembly Procedure The reassembly procedure is the reverse of the disassembly procedure. Note: Carefully clean all components, blow them off with compressed air to remove dirt, coat them with hydraulic oil, and then reassembly them. Apply silicon grease to the cylinder cap and then reinstall the cap. Apply MP grease to the end of the push rod.
8-50 Point Operations [Point 1] Adjust the input piston stroke. 1. Install the plate washer. 2. Place the snap ring onto the input piston. 3. Screw on the lock nut and adjust the input piston stroke. Standard: A = 12.7 ± 1.0 mm (0.5 ± 0.039 in) A 4. Tighten the lock nuts. 5. Reinstall the snap ring. Inspection: After reassembly, check the brake hydraulic pressure. (See page 24-56) When lower than the standard value: Enlarge dimension A. When higher than the standard value: Decrease dimension A. [Point 2] Inspection: Measure the free length of the compression spring. Standard: 21mm (0.83 in) Limit: 18.9mm (0.744 in) [Point 3] Make sure the cylinder cap is reinstalled in the correct orientation. SST 09471-22000-71 SST [Point 4] Inspection: Measure the free length of the valve return spring. Standard: 21.9mm (0.862 in) Limit: 19.7mm (0.776 in)
8-51 BRAKE VALVE OPERATION INSPECTION SST Union 1. Remove the lower panel and toe board. 2. Depressurize the accumulator. (Refer to page 8-46) 3. Remove the plug in the pressure testing opening of the brake valve, attach the union there, then attach an oil pressure meter via the SST. Union 47711-21320-71 SST 09472-22000-71 4. With the engine idling, measure the oil pressure when the brake pedal is fully depressed to the stroke end. MPa (kgf/cm 2 ) [psi] Vehicle model Standard 2 ton class 5.9 ~ 6.9 (60.2 ~ 70.4) [855.5 ~ 1000.5] 3, J3.5 ton class 6.9 ~ 7.9 (70.4 ~ 80.6) [1000.5 ~ 1145.5] 5. Raise the engine idle speed to 1000 rpm, turn the steering left and right until full lock 4-5 times to build maximum pressure in the accumulator, then cut the engine. 6. With the engine stopped, measure the oil pressure when the brake pedal is fully depressed to the stroke end. MPa (kgf/cm 2 ) [psi] Vehicle model Standard 2 ton class 5.0 (51.0) [725.0] or more 3, J3.5 ton class 5.5 (56.1) [797.5] or more
8-52 ACCUMULATOR ASSY REMOVAL INSTALLATION Note: Depressurize the accumulator before starting the operation. (Refer to page 8-46) T = N m (kgf cm) [ft lbf] 5 5 3 5 6 T = 32.4 ~ 48.6 (330 ~ 500) [23.9 ~ 35.9] Removal Procedure 1 Remove the front under cover and rear under cover. 2 Remove the lower panel and toe board. 3 Disconnect the wiring. 4 Remove the propeller shaft cover set bolt. 5 Disconnect the piping. 6 Remove the accumulator ASSY. Installation Procedure The installation procedure is the reverse of the removal procedure. Note: After installation, bleed air from the brake. (Refer to page 8-46) After installing check the operation of the accumulator. (Refer to page 8-55)
DISASSEMBLY INSPECTION REASSEMBLY 8-53 T = N m (kgf cm) [ft lbf] 1 T = 39 ~ 45 (400 ~ 460) [28.8 ~ 33.2] 1 T = 39 ~ 45 (400 ~ 460) [28.8 ~ 32.2] T = 17.5 ~ 22.5 (180 ~ 230) [12.9 ~ 16.6] T = 100 ~ 136 (1000 ~ 1400) [73.8 ~ 100.3] 2 T = 39 ~ 45 (400 ~ 460) [28.8 ~ 32.2] 3 T = 28 ~ 42 (300 ~ 400) [20.7 ~ 31.0] Disassembly Procedure 1 Remove the fitting, pressure switch, and check valve. 2 Remove the relief valve. 3 Remove the accumulator. Installation Procedure The installation procedure is the reverse of the removal procedure.
8-54 ACCUMULATOR INSPECTION SST Union Function inspection 1. Remove the lower panel and toe board. 2. Depressurize the accumulator. (Refer to page 8-46) 3. Remove the plug in the pressure testing opening of the brake valve, attach the union there, then attach an oil pressure meter via the SST. Union 47711-21320-71 SST 09472-22000-71 4. Raise the engine idle speed to 1000 rpm, turn the steering left and right until full lock 4-5 times to build maximum pressure in the accumulator, then cut the engine. 5. With the engine stopped. Depress the brake pedal fully to its stroke end, then release it. Wait 30 seconds, then depress and release the pedal again. 6. After repeating item 5 ten times, inspect the oil pressure when the pedal is depressed for the 11th time. Standard: 3.3MPa (33.7Kgf/cm 2 ) [478.5 psi] or more Note: If it is outside the standard, replace the accumulator. 7. With the engine stopped, depress the brake pedal fully to the stroke end, and hold it like this for 10 minutes. Check that the difference in the pressure values at the time when the pedal is first depressed, and at 10 minutes afterwards is zero. Note: If there is a difference in the pressures, clean the check valve and relief valve, check for damage to the seat part, and if there are no abnormalities, replace the part. Accumulator alarm inspection (Export model) 1. Raise the engine idle speed to 1000 rpm, turn the steering left and right until full lock 4 ~ 5 times to build maximum pressure in the accumulator, then cut the engine. 2. With the engine stopped, turn the key to the ACC position, depress the brake pedal fully to its stroke end, then release it. 3. Repeat 2., and inspect the pressure at which the alarm sounds. Alarm starts: 3.7 ~ 4.1MPa (37.7 ~ 41.8kgf/cm 2 ) [536.5 ~ 594.5 psi] 4. Once the alarm has sounded, start the engine, and with the engine idling, depress the brake pedal and inspect the pressure at which the alarm stops. Alarm stops: 4.7 ~ 5.5MPa (47.9 ~ 56.1kgf/cm 2 ) [681.5 ~ 797.5 psi]
8-55 PARKING BRAKE ASSY DISASSEMBLY INSPECTION REASSEMBLY T = N m (kgf cm) [ft lbf] 2 T = 32.4 ~ 48.6 (330 ~ 500) [23.9 ~ 35.9] 4 6 T = 13.7 ~ 25.4 (140 ~ 260) [10.1 ~ 18.7] 5 5 3 Disassembly Procedure 1 Remove the front axle & differential ASSY. (see page 4-12) 2 Remove the rear cover. 3 Remove the brake disc, plate No.2 and plate No.1. [Point 1] 4 Remove the retainer. 5 Remove the stopper bolt bracket, fork, and shaft. [Point 2] 6 Remove the oil seal. [Point 3] Reassembly Procedure The reassembly procedure is the reverse of the disassembly procedure. Note: During reassembling, check that no foreign matter is attached to the parts.
8-56 Point Operations [Point 1] Inspection: Measure the thickness of plate No.1. Except Pn3 ton series Standard: 1.2 mm (0.047 in) Limit: 1.0 mm (0.039 in) Pn3 ton series Standard: 1.5 mm (0.059 in) Limit: 1.3 mm (0.051 in) Inspection: Measure the thickness of plate No.2. Except Pn3 ton series Standard: 9.0 mm (0.354 in) Limit: 8.8 mm (0.35 in) Pn3 ton series Standard: 9.5 mm (0.374 in) Limit: 9.3 mm (0.366 in) Inspection: Measure the thickness of the brake disc. Standard: 1.6 mm (0.063 in) Limit: 1.2 mm (0.047 in) Align the notches in the brake disk and the reduction gear and reassemble them. (Pn2, Cu2 3 ton series) Notch
8-57 Hole Align the positions of the holes in the brake discs and reassemble them. (Pn3 ton series) Hole Fork [Point 2] Align the punch marks in the fork and shaft to reassemble them. Punch Marks Engage the spline so that the lever is vertical when the fork is level. Fork level If the spline engagement of the fork and shaft is out by one tooth, the result will be as shown in the drawing to the left. (Reference) A [Point 3] Using a pin, tap the new oil seal in from the edge of the rear cover to the position A. Standard: A = 5.0 ~ 5.5 mm (0.20 ~ 0.22 in) After reassembly, apply MP grease to the lip section of the oil seal.
8-58 PARKING BRAKE FUNCTION INSPECTION Checking the operation of the parking brake warning alarm (Export model) and pilot lamp If the parking brake warning alarm and pilot lamp do not operate as below, adjust the parking switch. 1. Check that the light turns on when the parking pedal is depressed. 2. Check that the light turns off when the parking pedal is released. 3. When travelling at 1.2 mph (2 km/h) without releasing the parking pedal, the alarm sounds. 4. When leaving the dirving seat without locking the parking pedal, the alarm sounds. (Export model) 50 ~ 100 N (5.1 ~ 10.2 kgf) [11 ~ 22 ft] Parking brake lever Stopper Bolt ADJUSTING THE PARKING LEVER SWITCH 1. After reassembling the disk, pull the end of the parking brake lever and adjust the clearance A between the tip of the stopper bolt and the parking brake lever. Lock the stopper bolt with the nut. A = 3.0 ~ 3.6 mm (0.12 ~ 0.14 in) Parking brake lever Stopper Bolt 2. The parking brake limit switch can be adjusted by the following procedure. (1) Insert a 0.5 mm (0.02 in) thickness gauge between the stopper bolt and parking brake lever. 0.5 mm (0.02 in) Switch end Bolt for switch (2) Bring the bolt for the switch into contact with the switch end, and lock the bolt for the switch with a lock nut, in the position where the switch is ON. (3) Insert a 1.5 mm (0.059 in) thickness gauge between the stopper bolt and the lever, and check that the switch turns OFF. 1.5 mm (0.059 in)
8-59 A PARKING BRAKE INSPECTION AND ADJUSTMENT 1. Check the set position of the parking brake cable. Standard: A = 0 ~ 2 mm (0 ~ 0.079 in) 2. Apply chassis grease to the points indicated by arrows in the illustration. For LH For RH When using SST (A) SST 3. Inspect and adjust the operating force of the parking brake pedal. (1) Attach the SST to the pedal. SST 09460-26600-71 (2) Attach a spring balance to the SST, and pull the reverse end to measure the operation force. When not using SST Standard: (A) When using the SST 112 ~ 136 N (11.4 ~ 14.0 kgf) [25.1 ~ 30.6 lbf] (B) When not using the SST 185 ~ 225 N (19.0 ~ 23.0 kgf) [42.0 ~ 51.0 lbf] (B) (3) If the operation force is outside of the standard, release the parking brake and adjust with the adjusting part. Clockwise: Strong operation force Counter clockwise: Weak operation force ADJUSTING THE RELEASE LEVER CABLE 1. Use the release cable adjust nut to adjust so that the play at the tip of the release lever is about 0 ~ 5 mm (0 ~ 0.197 in). Adjust nut Release lever
8-60 BRAKE COOLING OIL TANK REMOVAL INSTALLATION T = N m (kgf cm) [ft lbf] 4 4 5 T = 000 ~ 000 (000 ~ 000) 6 Removal Procedure 1 Remove the lower panel and toe board. 2 Remove the under cover. 3 Drain the brake cooling oil. (Refer to page 8-63) 4 Disconnect the piping. 5 Remove the brake cooling oil tank. 6 Remove the oil filter and fitting. [Point 1] Installation Procedure The installation procedure is the reverse of the removal procedure. Point Operations [Point 1] Inspection: Inspect and clean the oil filter.
8-61 PROCEDURE FOR POURING IN BRAKE COOLING OIL 1. Pour 4.8 l (1.27 US gal) into the tank. 2. Start the engine and allow the brake cooling oil to fill inside the brakes. 3. Pour brake cooling oil into the tank again, checking the amount on the level gauge. Inspect the oil amount by putting the level gauge cap part on the top end of the lubrication hole. (Do not push the cap part into the lubrication hole). cooling oil amount for each part (guide) Oil to be used: Shell Donax TD Oil amount l (US gal) Inside tank 4.8 (1.27) Piping 0.8 (0.211) Inside the brake 1.6 (0.422) Inside the cooler 0.8 (0.211) Total 8.0 (2.112)
8-62 BRAKE COOLING OIL COOLER REMOVAL INSTALLATION T = N m (kgf cm) [ft lbf] 1 2 5 6 Removal Procedure 1 Remove the radiator cover. 2 Remove the counter weight. 3 Drain the oil inside the brake cooling oil cooler. (Refer to page 8-63) 4 Disconnect the piping. 5 Remove the brake cooling oil cooler. Installation Procedure The installation procedure is the reverse of the removal procedure.
8-63 BRAKE PEDAL INSPECTION AND ADJUSTMENT Stop lamp switch A Reference value 135 ~ 140 mm (5.31 ~ 5.51 in) D (11.0 mm (0.43 in)) B Toe board Floor mat 1. Inspect the brake pedal height A. (From the toeboard to the upper surface of the pedal) Standard: A = 145 ~ 150 mm (5.71 ~ 5.91 in) (with pedal pad) If outside of the standard, adjust with the projection amount of the stopper lamp switch. 2. Inspect the brake pedal play B. Standard: B = 1 ~ 5 mm (0.039 ~ 0.197 in) If outside of the standard, adjust with the brake valve push rod length. 3. After adjusting, depress the brake pedal fully, and check the remaining depression margin D. Standard: D = 90 mm (3.54 in) or more
8-64 INCHING PEDAL INSPECTION AND ADJUSTMENT pedal link Adjusting nut B A Stopper bolt C Inching pedal plate Floor mat (135 ~ 140 mm (5.31 ~ 5.51 in)) (145 ~ 150 mm (5.71 ~ 5.91 in)) Toe board Adjusting nut Inching lever 1. Inspect and adjust the height and play of the brake pedal. (Refer to page 8-65) 2. Inspect the stroke A until the inching pedal links with the brake (the pedal stroke amount until the inching pedal plate contacts with the brake link). Standard: A = 26 ~ 36 mm (1.02 ~ 1.26 in) If outside of the standard, adjust with the projection amount of the stopper bolt. Here, adjust so that the shift in the height of the brake pedal is within 15 mm (0.59in). 3. Inspect and adjust the inching cable. (1) Inspect the set dimension B of the inching cable on the pedal side. Standard: 17.5 mm (0.689 in) If outside of the standard, adjust with adjusting nut on the pedal side. (2) Inspect the play C of the inching pedal until the inching lever starts to move. Standard: C = 1 ~ 3 mm (0.04 ~ 0.12 in) If outside of the standard, adjust with adjusting nut on the inching lever side.
8-65 INSPECTION AND ADJUSTMENT OF THE SINGLE BRAKE (INCHING) PEDAL Adjusting bolt Inching pedal No Clearance (a) pedal plate link Push rod Adjusting nut B Stopper bolt A C Floor mat (140 ~ 145 mm (5.51 ~ 5.71 in)) (150 ~ 155 mm (5.91 ~ 6.10 in)) Toe board (11 mm (0.43 in)) Adjusting nut Inching lever 1. Tighten the adjusting bolt until the clearance between the side (a) of the inching pedal and the tip of the adjustment bolt is gone, then lock it with the lock nut. 2. Adjust the pedal height and play. Use the standard value on this page for the pedal height, and refer to page 8-65 for the adjustment method. 3. Inspect the stroke A until the inching pedal links with the brake (the pedal stroke amount until the inching pedal plate contacts with the brake link). Standard: A = 61.7 ~ 68.6 mm (2.43 ~ 2.70 in) If outside of the standard, adjust with the push rod length. 4. Inspect and adjust the inching cable. (1) Inspect the set dimension B of the inching cable on the pedal side. Standard: B = 17.5 mm (0.69 in) If outside of the standard, adjust with adjusting nut on the pedal side. (2) Inspect the play C of the inching pedal until the inching lever starts to move. Standard: C = 1 ~ 3 mm (0.039 ~ 0.118 in) If outside of the standard, adjust with adjusting nut on the inching lever side.
8-66 GREASING TO PARKING BRAKE PEDAL RELEASE PIN After servicing the parking brake pedal, and every year or every 2000 hours, apply grease (molybdenum disulfide grease) to parking brake pedal release pin. Release pin