633GC Cut-Off Saw Shop Manual

Transcription

1 633GC Cut-Off Saw Shop Manual

2

3 633GC SHOP MNUL TBLE OF CONTENTS SECTION SECTION TITLE PGE NUMBER SHOP MNUL USE 2 1 TOOLS 3 2 SW SPECIFICTIONS 4 3 SERIL NUMBER LOCTION 5 4 SPRE PRTS DIGRM (TORQUE ND LOCTITE ) 6 5 IR INTKE 14 6 SPRK PLUG 16 7 CLUTCH & RIM SPROCKET 18 8 STRTER SYSTEM 22 9 WLLWLKER CYLINDER COVER MUFFLER CRBURETOR CYLINDER & PISTON WTER HOSE & CP IGNITION COIL FLYWHEEL BOTTOM GURD FRONT HNDLE FUEL TNK CRNKCSE BR STUD TENSIONER CRBURETOR TUNING IDLE SPEED DJUSTMENT TROUBLESHOOTING DIGRMS TROUBLESHOOTING: FUEL SYSTEM LEKS TROUBLESHOOTING: CRNKCSE LEKS 72 PPENDIX 1. SPRK PLUG REFERENCE GUIDE 73

4 SHOP MNUL USE 633GC SHOP MNUL Shop Manual Use This manual contains all the technical information necessary for carrying out repairs on the 633GC cut-off saw. For safe, efficient work, it is of prime importance that the values indicated be adhered to. Routine periodic maintenance is covered in the operator s manual included with each cut-off saw. General Shop Rules lways use the right tools for the job, otherwise components may be damaged. Use a plastic dead blow mallet to separate parts attached solidly to each other. Mark mating parts as a reassembly reference. Keep component parts together as a group. ssemble screws and nuts into appropriate subgroups. When reassembling, clean all parts carefully, lubricate moving parts and replace all oil seals, o-rings, gaskets, washers and self-locking nuts. For best results, use only original ICS replacement parts. General Recommendations Some procedures in this manual require the use of special tools. complete tool kit for the 633GC is available from ICS. Detailed carburetor maintenance and overhaul information is available in Walbro s Diaphragm Carburetor Service Manual. Walbro can be contacted at or by calling

5 633GC SHOP MNUL 633GC Service Tool Kit - P/N TOOLS P/N DESCRIPTION SCRENCH PRESSURE GUGE BULB COIL/FLYWHEEL TIMING SHIM CYLINDER SSEMBLY CLMPS & PISTON STOP SHOCK BSORBER TOOL SPRK TESTER FLYWHEEL DISSSEMBLY TOOL LIMITER CP REMOVL TOOL ELECTRONIC TCHOMETER GC INDUCTION SEL FLNGE W/ SCREWS GC EXHUST SEL FLNGE W/SCREWS TUNING SCREWDRIVER GC FLYWHEEL PULLER GC FUEL PRESSURE CP GC & 633GC MIN BERING DRIVER TOOL MIN BERING SPCING TOOL GC SHOCK BSORBER TOOL GC INTKE PORT COVER TOOL GC EXHUST PORT COVER TOOL 3

6 2. SPECIFICTIONS 633GC SHOP MNUL Specifications Engine Type Displacement Horsepower Engine Speed Piston ring gap (Maximum) Chain Speed Weight Cutting Depth Dimensions Carburetor ir Filtration Starter Ignition Spark plug type Clutch Fuel Mix Ratio Fuel Capacity Water Supply Noise Level Vibration Level Cutting Rate 2-Stroke Single Cylinder ir Cooled 6.2 cu.inch (101 cc) 6.1 hp ( rpm 11,500 ± 500 rpm, mechanically governed idle.040 in. (1 mm) 4950 fpm (25 m/s), free running 4000 fps (20 m/s), in the cut 27.5 lbs. (12.5 kg) Up to 16 inches (40.6 cm) 23 inches (58 cm) length 14 inches (35 cm) height 12 inches (30 cm) width Walbro diaphragm WGK3 w/ throttle shaft seals Washable cotton (K&N) or washable dry nylon Dust and water shielded Electronic, water sealed Champion RCJ-7Y (for conversion chart see appendix) Three-weight, single spring, centrifugal 25:1 gasoline to oil with oil brand name gasoline and ICS 2-stroke engine oil, or other high quality 2-stroke engine oil for air cooled engines..26 gal (1 liter) minute run time Minimum 20 psi (1.5 bar) meter 8 front handle Hard aggregates w/ steel: sq-in/min ( sq-cm/min) Medium aggregates: sq-in/min ( sq-cm/min) Masonry, soft aggregates: sq-in/min ( sq-cm/min) 4

7 633GC SHOP MNUL 3 This section shows the two locations of the serial number. 3. SERIL # LOCTION 5

8 4. SPRE PRTS DIGRM 4 This section covers torque, Loctite, and lubrication requirements of the individual components. The key numbers used are not related to the key numbers in the 633GC Replacement Parts Price List. 633GC SHOP MNUL TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 1 STRTER ROPE STRTER ROPE RETINER STRTER ROPE HNDLE STRTER HOUSING OIL CP SCREW 5 43 X STRTER COVER STRTER ROPE WSHER STRTER COIL SPRING & HOUSING STRTER SPRING COVER STRTER BUSHING STRTER ROPE PULLEY STRTER PULLEY WSHER STRTER PULLEY SCREW 3 26 X STRTER PULLEY COVER STRTER PULLEY COVER SCREW 2 17 X STRTER COVER DUST SHIELD STRTER COVER SSEMBLY (COMPLETE) IGNITION TOGGLE SWITCH IGNITION TOGGLE PLTE ON/OFF IGNITION TOGGLE SWITCH NUT SPRK PLUG CP SPRK PLUG CP SPRING IGNITION COIL WITH SPRK PLUG LED & PRIMRY 6 52 X IGNITION COIL MOUNTING SCREW WSHER FLYWHEEL MOUNTING WSHER FLYWHEEL MOUNTING NUT STRTER PWL KIT FLYWHEEL SSEMBLY REPLCEMENT KIT

9 633GC SHOP MNUL 4. SPRE PRTS DIGRM TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 1 SPRK PLUG WSHER CYLINDER BLOCK BOLT X CYLINDER TO MUFFLER GSKET EXHUST PIPE WRIST PIN NEEDLE BERING EXHUST PIPE MOUNTING SCREW CRNKSHFT SEL FLYWHEEL SIDE MUFFLER BODY MUFFLER SUPPORT BRCKET SCREW 4 43 X MUFFLER SUPPORT BRCKET NUT X MUFFLER SUPPORT BRCKET MUFFLER SCREW LOCKING PLTE MUFFLER MOUNTING SCREW CYLINDER BSE GSKET PISTON RING PIR WRIST PIN SNP RING PISTON WRIST PIN COMPLETE CYLINDER/PISTON SSEMBLY CRNKSHFT FLYWHEEL WOODRUFF KEY CRNKSHFT BERING (FLYWHEEL END) CRNKSHFT SSEMBLY CRNKSHFT BERING (CLUTCH SIDE) CRNKCSE OUTSIDE SEL-CLUTCH SIDE

10 4. SPRE PRTS DIGRM 633GC SHOP MNUL 8

11 633GC SHOP MNUL 4. SPRE PRTS DIGRM TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 1 CRNKCSE LEFT HLF CRNKCSE RIGHT HLF BOLT WSHER TRIGGER ROD GROMMET TRIGGER ROD BUSHING BUMPER, SHOCK BSORBER, FUEL TNK TOP CHOKE LEVER GROMMET CHOKE LEVER FUEL LINE GROMMET (CRNKCSE) MIN BERING SEL HOUSING SSMBLY-CLUTCH SIDE SCREW 8 69 X BR MOUNTING STUD X CRNKCSE GSKET CRNKCSE DOWEL PIN PREMIUM TENSIONER KIT (REPLCES 73283), SSEMBLY BR MOUNT PD COVER PLTE SCREW X WSHER CRNKCSE OUTSIDE SEL-CLUTCH SIDE CRNKCSE PLUG O-RING CRNKCSE PLUG SEL HOUSING O-RING SEL HOUSING MOUNTING SCREW (3) 3 26 X CLUTCH SIDE MIN BERING SEL-INSIDE WTER TUBE (IN TNK) WTER TUBE FITTING TUBE FITTING-BCKSIDE BR MOUNT COVER GURD MOUNTING WSHER COVER GURD MOUNTING BOLT 3 26 X COVER GURD WTER TUBE O-RING GC PLSTIC CP Not Shown. Gasket Set, includes parts 73434, 73436,

12 4. SPRE PRTS DIGRM 633GC SHOP MNUL TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 5 WSHER SHOULDER SCREW, HND GURD X GC SIDE COVER PLUG KIT GC HND GURD SCREW COVER SIDE BR PLTE RUBBER BUMPER, COVER COVER RUBBER FLP SIDE COVER W/O BRKE COMPONENTS COVER CLMPING NUT CLUTCH SPCER WSHER CLUTCH NEEDLE BERING CLUTCH CUP WITH SPLINED DPTER CLUTCH SPRING CLUTCH SSEMBLY T RIM SPROCKET KIT CLUTCH SHIELD CHIN COVER RUBBER INSERT-MIDDLE CHIN COVER RUBBER INSERT-TOP GC HND GURD SCREW GC CLUTCH SPCER

13 633GC SHOP MNUL 4. SPRE PRTS DIGRM TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 1 FILTER COVER KNOB WSHER FILTER KNOB O-RING IR FILTER COVER SSEMBLY SCREW 5 43 X CYLINDER COVER CRBURETOR TTCHMENT SCREW 5 43 X CRBURETOR TTCHMENT SCREW WSHER INTKE MNIFOLD RUBBER INTKE MNIFOLD BRCKET FILTER CNNISTER COVER O-RING, IR FILTER IR FILTER GSKET IR FILTER CNNISTER, POLY FILTER CNNISTER GSKET PREFILTER PLSTIC, SECONDRY FILTER FILTER SUPPORT SCREW 5 43 X FILTER SUPPORT CRBURETOR STNDOFF SUPPORT BOLT 6 52 X CRBURETOR SUPPORT SCREW 3 26 X CRBURETOR MIXTURE SCREW GROMMET CRBURETOR INSULTOR TO CYLINDER GSKET CRBURETOR INSULTOR INSULTOR FOM GSKET CRBURETOR TO INSULTOR GSKET

14 4. SPRE PRTS DIGRM 633GC SHOP MNUL TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 1 FRONT HNDLE SSEMBLY WSHER FRONT HNDLE BOLT 5 43 X TRIGGER LOCK PIN TRIGGER LOCK PIN WSHER TRIGGER LOCK SPRING TRIGGER LOCK BUTTON TRIGGER PIVOT PIN THROTTLE LEVER TRIGGER LOCKOUT LEVER TRIGGER LOCKOUT LEVER SPRING FUEL TNK SSEMBLY SCREW 7 61 X THROTTLE OPERTING WIRE MOUNTING NUT RER HNDLE RER BOLT 3 26 X RER HNDLE SSEMBLY FUEL CP SSEMBLY FUEL CP O-RING FUEL TNK SCREW FUEL FILTER FUEL LINE FUEL BRETHER PIPE SHOCK BSORBER 5 43 X WSHER SCREW (RER HNDLE, UPPER) 3 26 X BUMPER, SHOCK BSORBER, FUEL TNK TOP

15 633GC SHOP MNUL 4. SPRE PRTS DIGRM TORQUE LOCTITE KEY DESCRIPTION Nm in lbs. 272 PRT NUMBER 34 COVER GURD FRONT MOUNT NUT HOSE HNGER BUTTON FITTING WLLWLKER SIDE RM SCREW X FITTING COPPER WSHER GC WTER CP FUEL CP O-RING WTER HOSE HOSE HNGER HOSE CLMP WTER HOSE SCREW GURD FLP CLMP GURD FLP GURD FLP WSHER WTER HOSE COVER WTER SHUT-OFF VLVE WTER HOSE O-RING RING NUT FITTING WTER HOSE GSKET WSHER GURD FLP SPCER GC WLLWLKER LEVER RM GURD FLP SCREW

16 5. IR INTKE 5 This section covers the disassembly, inspection, and assembly of the air intake. 633GC SHOP MNUL 5.1 Loosen the air filter cover screw and remove air filter cover. 5.2 Remove filter canister cover and air filter. B Inspect air filter. Replace filter if necessary (P/N 71752) 5.3 Remove pre filter from air filter mount. B Clean filter with cleaning solution and water. Let dry and reinstall. 14

17 633GC SHOP MNUL 5.4 Secure air filter mount screws (3). B Make sure filter canister gasket and air filter water seal are secure. Replace air filter water seal if it is damaged, permanently depressed, hard due to slurry, or missing (P/N 71719). 5.5 ssemble filter system in the reverse order. 5. IR INTKE 15

18 6. SPRK PLUG 6 This section covers the removal, inspection, and installation of the spark plug. 633GC SHOP MNUL 6.1 Remove the spark plug lead. 6.2 Clean area around the spark plug to prevent debris from entering the cylinder. 6.3 Remove the spark plug. 6.4 Inspect the spark plug. If dirty clean with a wire brush as shown. 16

19 633GC SHOP MNUL B Gap if necessary to 0.20 (0.5 mm). NOTE: If the sparkplug must be replaced refer to the Spark Plug Reference Guide on page SPRK PLUG 6.5 ssemble in the reverse order. Make sure the plug boot is seated completely. 17

20 7. CLUTCH & RIM SPROCKET 7 This section covers clutch removal, rim sprocket removal, inspection, and assembly. Refer to sections 5 and 6 if necessary. 7.1 Insert piston stop tool into spark plug hole. 633GC SHOP MNUL 7.2 Pull starter handle until piston stops against tool. 7.3 Remove clutch shield with small screwdriver. 18

21 633GC SHOP MNUL 7.4 Remove clutch. Left hand threads - rotate clockwise to loosen. NOTE: If an impact wrench is available steps 7.1 and 7.2 do not have to be performed. 7. CLUTCH & RIM SPROCKET 7.5 Remove all drive components. 7.6 Inspect the clutch shoes for wear. Replace if the shoe has less than 0.04 (1 mm) of material, as shown. 19

22 7. CLUTCH & RIM SPROCKET 7.7 Inspect spring for cracks. 633GC SHOP MNUL 7.8 ssemble clutch shoes as shown. 7.9 Finish installation of clutch shoe as shown. 20

23 633GC SHOP MNUL 7.10 Inspect the rim sprocket for wear. Replace if the rim sprocket teeth are worn to points, as shown on right. 7. CLUTCH & RIM SPROCKET 7.11 Clean and assemble. B C Clean all parts in solvent. Grease clutch cup bearing with a waterproof grease (ICS P/N 70885). ssemble clutch: use spacer washer, bearing, clutch cup with rim sprocket, inside clutch spacer washer, and clutch assembly Install clutch. Tighten firmly. Left hand threads. 21

24 8. STRTER 8 This section covers the removal of the starter cover, replacement of the starter rope, and replacement of the recoil spring. 633GC SHOP MNUL 8.1 Remove starter cover screws. 8.2 Remove starter cover assembly from saw. 8.3 Remove starter cord shield screws. 8.4 Relieve spring tension. B C Pull 4-6 (10-15 cm) of rope out. Line rope up with notch on pulley. Slowly rotate pulley counterclockwise until spring pressure is released. Use thumb as a brake. 8.5 Remove starter pulley screw and washer. NOTE: Hold starter cover firmly. 22

25 633GC SHOP MNUL 8.6 Remove starter pulley. 8. STRTER 8.7 Inspect coil spring. Replace if spring hook is damaged. ttempting to re-bend the spring hook may cause the hook to break off. B Carefully remove coil spring and housing to prevent spring from unwinding. 8.8 pply light weight oil. 8.9 Replace parts carefully. 23

26 8. STRTER 8.10 Inspect pulley spring catch. Clean with cleaning solution. B Replace if worn or broken. 633GC SHOP MNUL 8.11 Install starter rope and tie knot Install pulley Wind rope onto pulley clockwise leaving 4-6 (10-15 cm) out. B Make sure that the pulley spring catch is in the spring hook Install center screw. Use blue Loctite. B Torque to 26 in-lbs. (2.9 Nm). 24

27 633GC SHOP MNUL 8.14 Wind the recoil spring. B C Line rope up with notch on pulley. Rotate the pulley with the rope clockwise 5 times. Untangle rope and release. 8. STRTER 8.15 ssemble starter cord shield Remove starter pawl snap rings, pawls, spring, and plain washer Inspect and clean pawl components. B Inspect the components. Replace if necessary. Clean the components with a brush and solvent. 25

28 8.18 ssemble components B 8. STRTER Make sure the snap ring spring is in the correct position. Make sure the spring is in the correct position. 633GC SHOP MNUL 8.19 Install starter cover. Pull out cord 4-6 (10-15 cm). Slowly release while placing cover to allow pawls to engage Install starter cover screws. Use blue Loctite. B Torque to 60 in-lbs. (6.8 Nm). 26

29 633GC SHOP MNUL 9 This section covers the removal, inspection, and assembly of the WallWalker and guard flap. 9. WLLWLKER 9.1 Inspect WallWalker tip. If the tip is worn as shown, replace. 9.2 Remove crankcase screws and wave washers. 9.3 Remove WallWalker from saw. 9.4 Remove guard flap screws and washer. 9.5 Remove and inspect guard flap. Replace the flap if it is torn or damaged in any way. 27

30 9.6 ssemble in the reverse order. Install crankcase screws and wave washers. B Use blue Loctite. C 9. WLLWLKER Torque to 70 in-lbs. (7.9 Nm). 633GC SHOP MNUL 28

31 633GC SHOP MNUL 10 This section covers the disassembly and assembly of the cylinder cover. Removal of the air intake components and front handle is required. Refer to sections 5 and 18 if necessary. 10. CYLINDER COVER 10.1 Remove the cylinder cover screws Remove spark plug lead from cylinder cover Partially remove intake manifold from cylinder cover while lifting cylinder cover away from saw Inspect cylinder cover for damage. Replace if necessary Make sure carburetor screw boot and cylinder cover plug are in place. 29

32 10.6 Install cylinder cover. B 10. CYLINDER COVER Pull spark plug lead into slot in cylinder cover. Push the cylinder cover down on the crankcase, guide intake manifold into cylinder cover. 633GC SHOP MNUL 10.7 Push down cylinder cover until it sits flat on crankcase. B Install the cylinder cover screws using blue Loctite. Torque to 35 in-lbs. (4.0 Nm). 30

33 633GC SHOP MNUL 11 This section covers the disassembly, inspection, and assembly of the muffler. Removal of the WallWalker and cylinder cover is required. Refer to sections 9 and 10 if necessary. 11. MUFFLER 11.1 Bend the corner of the muffler screw locking plate away from the muffler screw Remove muffler screws, muffler support bracket nut, and muffler assembly Clean and inspect parts of muffler assembly. Replace any damaged components Install muffler. ssemble muffler screws, muffler support bracket, muffler screw locking plate. B Thread muffler screws into cylinder; torque to 104 in-lbs. (11.75 Nm). C Bend muffler screw locking plate over flat edge of muffler screw. D Install muffler support bracket nut (use blue Loctite ); torque to 26 inlbs. (2.9 Nm). 31

34 12. CRBURETOR 12 This section covers the removal, and installation of the carburetor. Removal of several groups of components is needed. Refer to sections 5 and 10. If necessary, carburetor tuning is covered in section GC SHOP MNUL 12.1 Remove fuel line from carburetor and plug Remove choke lever from carburetor Remove carburetor attachment screws. 32

35 633GC SHOP MNUL 12.4 Remove intake manifold. 12. CRBURETOR 12.5 Remove carburetor. Lift and twist carburetor away from throttle linkage to remove ssemble in the reverse order. Torque carburetor body screws to 43 in-lbs. (4.9 Nm). 33

36 13. CYLINDER & PISTON 13 This section covers the disassembly, inspection and assembly of the cylinder, piston and related components. Removal of several component groups is required. Refer to sections 5, 6, 10, and 12 if necessary. 633GC SHOP MNUL 13.1 Remove insulator base screws. Remove carburetor insulator from cylinder Remove cylinder screws (4) and wave washers. 34

37 633GC SHOP MNUL 13.3 Remove cylinder. Remove cylinder gasket and clean case. 13. CYLINDER & PISTON 13.4 Remove wrist pin retaining clips 13.5 Press wrist pin out with an 8 mm deep socket Remove piston and inspect. Replace if damaged. 35

38 13. CYLINDER & PISTON 13.7 Remove wrist pin bearing. 633GC SHOP MNUL 13.8 Cylinder gasket B Oil gasket with ICS 2-stroke engine oil. Install gasket and align holes and notch Install wrist pin bearing in rod. Oil bearing with ICS 2-stroke engine oil. 36

39 633GC SHOP MNUL Install rings. 13. CYLINDER & PISTON Ring orientation Install one wrist pin retaining clip. 37

40 13. CYLINDER & PISTON Make sure wrist pin retaining clip is in the proper orientation. 633GC SHOP MNUL Lubricate wrist pin and partially install in piston lign piston in correct orientation. EXHUST INTKE 38

41 633GC SHOP MNUL Install piston. Oil piston with ICS 2-stroke oil. B lign wrist pin with wrist pin bearing. C Complete wrist pin installation. D Install second wrist pin retaining clip. 13. CYLINDER & PISTON Install cylinder Lubricate cylinder bore with ICS 2-stroke oil. B C Compress rings with ring compression tool. Slide cylinder onto piston, pushing ring compression tool down Install cylinder. B C Remove ring compressor. Slide cylinder onto piston and into crankcase. lign cylinder bolt holes with crankcase. 39

42 13.19 Install 4 cylinder screws and washers. Use blue Loctite. B 13. CYLINDER & PISTON Torque bolts to 104 in-lbs. (11.75 Nm). 633GC SHOP MNUL Install insulator base. Install insulator base screws, use blue Loctite and torque to 52 in-lbs. (6 Nm). 40

43 633GC SHOP MNUL 14 This section covers water hose and water tank cap. 14. WTER HOSE 14.1 Remove water connection from hose end Remove starter cover screw with hose hanger from saw Remove water hose connector Unscrew water tank cap from saw. 41

44 14.5 Release water tank cap from water tank tube. 14. WTER HOSE Depress orange fitting as shown ssemble in the reverse order. 633GC SHOP MNUL 42

45 633GC SHOP MNUL 15 This section covers the removal, inspection, and installation of the ignition coil. Removal of the starter is required. Refer to section 8 if necessary. 15. IGNITION COIL 15.1 Remove starter Remove starter flywheel shroud by unhooking wires Remove ignition coil screws, wave washers and plain washers Remove ignition coil Inspect. B Look for cracked/missing insulation. Clean flywheel magnets and coil if rusty. 43

46 15.6 Install Ignition coil. Place ignition coil shim (0.012 ) on magnet counterweight side of flywheel. B C D E F 15. IGNITION COIL Set ignition coil in place. Install ignition coil screws, wave washers, and plain washers with blue Loctite. Holding shim, rotate flywheel magnet around to coil. Torque ignition coil screws to 52 in lbs. (5.9 Nm). Remove shim, rotate flywheel to 633GC SHOP MNUL G check clearance. Route ignition stop switch wire through crankcase into carburetor chamber. Install wire grommet in crankcase Complete ignition wire routing and assemble saw in reverse order. 44

47 633GC SHOP MNUL 16 This section covers the removal, inspection, and installation of the flywheel. Removal of the starter and spark plugs is required. Refer to sections 6 and 8 if necessary. 16. FLYWHEEL 16.1 Remove sparkplug and insert piston stop Remove flywheel nut (counter clockwise), wave washer, and plain washer Install flywheel puller bolts (3) finger tight. Turn main puller bolt clockwise with wrench until flywheel releases from the crankshaft Inspect & clean flywheel. Replace if any of the fins are broken. 45

48 16. FLYWHEEL 16.5 Inspect woodruff key. Replace if broken or damaged. 633GC SHOP MNUL 16.6 Install flywheel, plain washer, wave washer, and flywheel nut. Torque nut to 390 in-lbs. (44 Nm). 46

49 633GC SHOP MNUL 17 This section covers the removal inspection, and installation of the bottom guard. 17. BOTTOM GURD B C D Remove bottom guard screws and split washers. Inspect bottom guard. Replace if damaged. ssemble in reverse order 47

50 18. FRONT HNDLE 18 This section covers the removal, inspection, and installation of the front handle. 633GC SHOP MNUL 18.1 Remove front handle screws on right side Remove front handle screws on bottom Install front handle. Roll front handle into place. B Install front handle screws (4). C Use blue Loctite. D Torque to 43 in-lbs. (4.9 Nm). 48

51 633GC SHOP MNUL 19 This section covers the disassembly, inspection, and assembly of the vibration isolaters, fuel tank, and rear handle. 19. FUEL TNK 19.1 Remove vibration isolator screws and wave washers on clutch side of saw Remove vibration isolator screws and wave washers on flywheel side of saw. NOTE: Flywheel and cylinder cover do not need to be removed to perform fuel tank maintenance. 49

52 19. FUEL TNK 19.3 Separate crankcase and fuel tank. NOTE: During assembly be careful not to kink the fuel line between the crankcase and fuel tank 633GC SHOP MNUL 19.4 Remove vibration isolators from fuel tank (6) if necessary Separate the fuel tank halves. B Remove the rear handle. Remove the screws (9) around the tank. 50

53 633GC SHOP MNUL 19.6 Separate the fuel tank halves using a large screwdriver. B Clean the joining surface of the tank halves. ssemble in the reverse order. NOTE: Use a fuel proof liquid gasket material to reseal the tank (Scotch Grip #847) when assembling fuel tank. 19. FUEL TNK 51

54 20. CRNKCSE 20 This section covers the disassembly, inspection, and assembly of the crankcase seals and crankshaft bearings. 633GC SHOP MNUL 20.1 Remove outer crankshaft seal housing screws and wave washers Remove crankcase bolts. 52

55 633GC SHOP MNUL 20.3 Heat the flywheel side of crankcase with heat gun to 150 F (65.5 C). 20. CRNKCSE 20.4 To remove the flywheel side of crankcase; tap crankshaft with plastic mallet. Suspend above work surface. B Tap with mallet Remove the flywheel side of crankcase seal. 53

56 20. CRNKCSE 20.6 Heat the clutch side of crankcase with heat gun to 150 F (65.5 C). 633GC SHOP MNUL 20.7 To remove crankshaft from the clutch side of crankcase. Tap crankshaft with a plastic mallet. Suspend above work surface. B Tap with plastic mallet Remove the bearing from the flywheel side of crank shaft. 54

57 633GC SHOP MNUL 20.9 Remove the bearing, seal, and bushing from the clutch side of crankshaft. 20. CRNKCSE Clean mating crankcase faces Heat crankcase halves to 150 F Install bearing into crankcase halves Tap with bearing driver and mallet. 55

58 20. CRNKCSE Repeat with other half. 633GC SHOP MNUL Install crankshaft into clutch side of case Place clutch side of crank case seal on crankshaft. Tap lightly with bearing driver and mallet. 56

59 633GC SHOP MNUL 20. CRNKCSE Coat crankcase gasket with ICS 2 stroke engine oil lign crankcase gasket on flywheel side crankcase pins Place crankcase halves together and align crankcase pins. 57

60 20. CRNKCSE ssemble crankcase halves; tap with bearing driver and mallet. 633GC SHOP MNUL Install main crankcase bolts. Use blue Loctite. B Torque to 70 in-lbs. (7.9 Nm). NOTE: Tighten bolts hand tight, then torque bolts in sequence listed at right Install flywheel side crankcase seal tap with bearing driver and mallet. 58

61 633GC SHOP MNUL Trim crankcase gasket flush. 20. CRNKCSE 59

62 21. BR STUD ND PD 21 This section covers the removal and installation of the bar studs and bar pad. 633GC SHOP MNUL 21.1 Remove bar studs. B C D Install side cover nuts, flange to flange. Tighten side cover nuts against each other. ttempt to remove the inside nut which should pull out the bar stud. Repeat on second bar stud ssemble in reverse order using blue Loctite. 60

63 633GC SHOP MNUL 22 This section covers the removal and installation of the chain tensioner. 22. TENSIONER 22.1 Remove bar plate to expose the chain tensioner Unscrew tensioner to remove. Remove tensioner pin. B Remove tensioner screw keeper ssemble in reverse order. 61

64 23. CRBURETOR TUNING 633GC SHOP MNUL 23 This section covers carburetor tuning. Included in this section are basic settings, idle speed adjustment, and complete adjustment. NOTES: The carburetor has been set at the factory for optimal performance and compliance to EP Phase I emissions standards. However, minor adjustments may be required in certain conditions, such as when operating at high elevation or after the saw has been rebuilt. This cut-off saws speed is mechanically governed by the carburetor. This will prevent the saw from going above 11,500 rpm. ttempting to set the carburetor mixture to increase the speed or power beyond this limit may seriously damage the engine. lways check the air filter, fuel filter, and spark plug before making carburetor adjustments and clean or replace if necessary. When adjusting the carburetor, turn the screws very little no more than 1/4 of turn at a time. Minor adjustments will have large effects on the engine. If the carburetor has to be readjusted completely, the limiter caps must be released before the basic setting can be made. Basic Setting if the carburetor needs to be completely readjusted, see following procedure: Pull limiter caps using ICS P/N B Gently turn both adjusting screws (H and L) clockwise as far as possible. C Turn screws counter-clockwise: H = 1 turn from closed L = 1 1/2 turns from closed Verification of rpm, with bar and no chain Idle = 3,000 ± 200 rpm Full throttle = 11,000 ± 500 rpm 62

65 633GC SHOP MNUL 23.1 Complete carburetor readjustment Look into adjustment screw hole. Observe orientation of the release slots on the adjustment screw limiter cap. 23. CRBURETOR TUNING 23.3 Insert the limiter cap puller blades into the release slots. B Firmly hold the tool shaft while screwing in the puller screw until the screw head is against the puller shaft. Unscrew the puller screw Using a 5/64 straight blade screwdriver, gently turn the adjustment screws clockwise until completely closed Set the adjustment screws at the Basic Setting: H = 1 turn counterclockwise from closed L = 1 1/2 turns counterclockwise from closed 63

66 23. CRBURETOR TUNING 23.6 Start the saw and warm up the engine. NOTE: The side cover must be held tightly in place with the side cover nuts, using a bar and no chain. Failure to do so may result in personal injury With a tachometer check the saw rpm, with no bar and chain: Idle = 3,000 ± 300 rpm If the idle rpm does not fall into this range, adjust the T screw slowly. 633GC SHOP MNUL 23.8 With a tachometer check the saw full throttle rpm, with no bar and chain: Target = 11,500 ± 300 rpm 23.9 If the full throttle rpm falls below this range, turn the H screw in (clockwise) 1/16 th of a turn at a time. Pulse the throttle to help stabilize the system. Do not hold the saw at maximum rpm for more than 5 seconds If the full throttle rpm falls above this range, turn the H screw out (counterclockwise) 1/16 th of a turn at a time. Pulse the throttle to help stabilize the system. Do not hold the saw at maximum rpm for more than 5 seconds. 64

67 633GC SHOP MNUL When the carburetor is adjusted correctly set the limiter caps with a ¼ straight blade screwdriver. B H = horizontal L = vertical 23. CRBURETOR TUNING 65

68 24. IDLE SPEED DJUSTMENT 24 This section covers idle speed adjustment. 633GC SHOP MNUL 24.1 If engine stops while idling: B C Make sure the chain is properly tensioned. Turn T screw clockwise until chain begins to move. Back T screw out ½ turn If chain turns at idle: Back T screw out until chain stops moving. 66

69 633GC SHOP MNUL 25. DIGRMS 25 This section provides several flowcharts to aid diagnosing common problems. CHECK POSSIBLE CUSE REPIR The engine runs rough at all speeds. YES Dirty or clogged air filter. Water has been ingested. Loose or dirty spark plug. Clean or replace the air filter. Inspect air intake sysetm for water. Inspect fuel system for water. tighten, clean, or rreplace spark plug. dirty air filter is the #1 reason for engine problems. The engine is overheating. YES Operator is overworking the saw. Carburetor mixture is too lean. Incorrect fuel/oil ratio. Flywheel fins are clogged. ir deflector is missing. Cylinder fins are clogged. See Operator s Manual. See Carburetor Tuning section. See Saw Specifications section. Clean flywheel fins with wire brush. See Starter Cover section. Clean cylinder fins. Poor acceleration. YES Dirty or clogged air filter. Clogged fuel filter. Incorrect carburetor tune. Plugged fuel tank breather. Blocked pulse tube. Clean or replace the air filter. Replace fuel filter. See Carburetor Tuning section. Repair or replace fuel tank breather. Replace pulse tube. Uneven idle or engine may run away. YES ir leak at intake boot, cylinder gasket, or crankcase gasket. Faulty carburetor diaphragm. Inspect air intake boot. Pressure test crankcase. Replace carburetor. Diamond chain moves at idle. YES Idle speed too high. Broken clutch spring. djust idle speed. Replace clutch spring. Excessive vibration. YES Damaged shock absorber. Damaged or broken flywheel fins. Bent crankshaft. Replace shock absorbers. Replace flywheel. Replace crankshaft. 67

70 25. DIGRMS 633GC SHOP MNUL Saw Will Not Start CHECK POSSIBLE CUSE REPIR Does the engine crank? NO Dirty or broken recoil starter Internal damage Clean, rebuild or replace the recoil starter Inspect for internal damage such as seized piston YES Is there spark? YES Is the spark plug firing properly? YES NO NO The ignition switch is OFF Faulty ignition ground Faulty spark plug lead Faulty ignition coil Plug is soaked with fuel The plug is fouled or gapped improperly Plug is internally faulty or the wrong type Move switch to ON and re-test Tighten connections or replace round wire Repair or replace spark plug lead Replace ignition coil Dry plug, expel excess fuel from cylinder and crankcase Clean and re-gap the plug to inch (0.05 mm) Replace with the correct plug See Spark Plug Reference Guide Check cylinder compression NO Loose spark plug If below 125 psi excess wear on the piston, cylinder, rings Tighten plug and re-test Replace piston and cylinder YES Is the fuel fresh? Is the fuel mixed 25:1 NO Fuel is old, varnished, or contaminated Empty tank and re-fill with fresh fuel of the correct mixture (50:1) YES Is the fuel reaching the carburetor? YES NO Clogged fuel filter Damaged fuel line Damaged pulse tube Plugged fuel tank breather Replace fuel filter Replace fuel line Replace pulse tube Repair or replace fuel tank breather Is too much fuel reaching the carburetor? YES Carburetor is tuned incorrectly Plugged fuel tank breather Refer to Carburetor Tuning section Repair or replace fuel tank breather NO Is the flywheel key sheared? YES Loose flywheel Replace key and reinstall flywheel 68

71 633GC SHOP MNUL 26 This section covers testing the fuel system for leaks. Engine starvation can result from a leak or malfunction of any of the main components of the fuel system. The five main components are the fuel tank, fuel tank breather, fuel filter, delivery tubes, and carburetor. 26. FUEL SYSTEM LEKS 26.1 Remove and inspect the fuel filter. Replace the fuel filter if there is any foreign material in the felt or the internal screen Test the main fuel pick-up tube for leaks. B C Install the pressure gauge and bulb to filter end of fuel line. Pressurize the tube to 7 psi (0.5 bar). If the pressure does not maintain, separate the fuel line from the carburetor. 69

72 D E F G 26. FUEL SYSTEM LEKS Plug one end of the main fuel pick-up tube. Re-pressurize the tube to 7 psi (0.5 bar). Replace the tube if pressure is not maintained. If the main fuel pick-up tube does maintain pressure, than the leak has been isolated to the carburetor. Refer to the Walbro Diaphragm Carburetor Service Manual. 633GC SHOP MNUL 26.3 The fuel tank breather stabilizes the pressure in the fuel tank preventing both excessive pressure, which could flood the engine, and negative pressure, which could starve the engine of fuel Testing the fuel tank breather. B ttach the pressure gauge and bulb to the fuel tank plug. Plug the fuel line at the carburetor end. Pressurize the tube to 4.5 psi (0.3 bar). The pressure should reduce to nearly 0 psi (0 bar) over about 3 seconds. 70

73 633GC SHOP MNUL 26.5 If the pressure does not reduce to 0 psi, disassemble or replace the breather. B C Clean the parts with fuel for the cut-off saw. ssemble in reverse order. Make sure that the spring taper is oriented in the correct direction. 26. FUEL SYSTEM LEKS 71

74 27. CRNKCSE 27 This section covers testing the crankcase for leaks. leak in the crankcase can cause the engine not to run or to run too lean. 633GC SHOP MNUL 27.1 Install the exhaust seal flange. Be sure the spark plug is installed and tightened firmly Install the intake seal flange Install the pressure gauge and bulb Pressurize the crankcase to 7 psi (0.5 bar) If the pressure does not remain the same, use soapy water to find the leak. NOTE: It is recommended that this test be performed after an engine rebuild. 72

75 633GC SHOP MNUL PPENDIX 1 The Spark Plug Reference Guide is to be used as a guide only. When trying a plug from a different manufacturer, perform a plug check to be sure that the plug will work. SPRK PLUG REFERENCE GUIDE ICS RESISTOR CHMPION NGK RESISTOR BOSCH RESISTOR RESISTOR RCJ7Y BPMR7 WSR7F 73

76 ICS, Blount Inc SE International Way Portland, Oregon TEL FX p/n 71537