0744-926 These numbers are required to complete warranty claims All materials and specifications are subject to change properly. No warranty will be allowed by Arctic Cat Inc. without notice. if the engine serial number or VIN is removed or muti- Keep this manual accessible in the shop area for refer- lated in any way.
Oil break-in. After the 10 hour break-in period, the snowmo- bile may be taken to an authorized Arctic Cat Snowmo- bile dealer for a checkup and oil change at the discretion and expense of the snowmobile owner.
Taking the snowmobile out of storage and correctly pre- 28.6 62.6 96.6 130.6 paring it for operation will assure many miles and hours 29.9 63.9 97.9 131.9 of trouble-free snowmobiling. Arctic Cat recommends the 31.3 65.3 99.3 133.3 following procedure to prepare the snowmobile. 32.6 66.6 100.6 134.6 1.
NOTE: Before engine assembly, ensure all threaded areas are clean to assure an accurate torque value is achieved. Torque values have a range of ± 20%. = Torque control required = Lubricate with Arctic Cat 4-Stroke Engine Oil = Apply Loctite = Lubricate with Arctic Cat All-Temp Grease 120-ENG10...
Engine Specifications Carburetor Specifications Engine Model Number 70CL1-030 Idle Fuel Adjuster Screw Main Jet Pilot Jet Float Height (Turns Out) Displacement 123 cc 77.5 37.5 0.63" No. of Cylinders Bore x Stroke 56 x 50 mm Track Specifications Cooling System Spark Plug (NGK) BPR4ES Spark Plug Gap...
This engine section has been organized into sub-sections showing a progression for the complete servicing of the Arctic Cat 120 cc engine. For consistency purposes, this section shows a complete and thorough progression; how- ever, for efficiency it may be preferable to remove and disassemble only those components needing to be addressed and to service only those components.
Disassembling 1. Remove the oil drain plug and drain the oil; then install the oil plug and tighten securely. A048 10. Lay the snowmobile on its side. NOTE: A piece of cardboard should be used to pro- tect the finish. 11.
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IO065A IO068 NOTE: For assembling purposes, note the location NOTE: If the cylinder head will be replaced, the car- of the governor arm spring before removing. buretor studs may be removed by tightening the two nuts against each other; then using a wrench on the 5.
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IO071 IO069B 12. Remove the lock nuts and rocker arm pivots securing 16. Using a flywheel puller, remove the flywheel. the rocker arms to the cylinder head. 13. Remove the push rods; then remove the push rod guide plate. IO074 17.
22. Note the relation of the connecting rod journal to the crankshaft and mark the connecting rod and end cap for reference during installation; then remove the cap screws and connecting rod end cap. IO077 19. With the piston at TDC, scribe an alignment mark on the gear of the camshaft directly in-line with the alignment dot on the crankshaft gear.
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CYLINDER HEAD/VALVE ASSEMBLY Measuring Valve Face Width 1. Using a micrometer, measure the width of the valve NOTE: Remove the valves by pressing down on the face. spring retainer and removing the valve keeper. Account for valve springs, spring retainers, and valve keepers.
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2. Acceptable width of valve seat contact width (mea- 2. Minimum valve spring free length must not exceed surement A) must be at least 0.03". 1.04". NOTE: With the crankshaft at top dead center on the compression stroke, install the valve springs and spring retainers;...
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PISTON ASSEMBLY NOTE: Oversized pistons are available allowing the cylinder to be bored oversized. NOTE: Whenever a piston, rings, or pins are out of tolerance, they must be replaced. Cleaning/Inspecting Piston 1. Using a non-metallic carbon removal tool, remove any carbon buildup from the dome of the piston.
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IO085 IO086 3. Piston skirt to cylinder clearance must be within Measuring Piston Pin Bore Diameter 0.0006-0.0016". 1. Insert an inside dial indicator into the piston-pin bore. 4. If the piston/cylinder clearance exceeds the limit, Take two measurements to ensure accuracy. bore the cylinder and use an oversized piston or 2.
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2. Check the gasket surface of the cylinder for distor- tion with a straightedge and thickness gauge taking a clearance reading at several places. If the largest reading at any position of the straightedge exceeds the limit, replace the cylinder. 3.
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2. Clearance measurement must be within 0.008-0.024". GEN-0039 CRANKSHAFT BEARINGS GEN-0036 MEASURING CRANK PIN/ CONNECTING ROD CLEARANCE 1. Measure the crank pin diameter. Measurement must be at least 1.102". 0744-992 Removing 1. Using a flat-blade screwdriver, carefully work the oil seal from side-to-side out of the crankcase and cover.
2. Inspect the sealing surfaces for trueness by placing NOTE: Coat the cylinder wall, connecting rod bear- each on the surface plate covered with #400 grit wet- ing surface, and the crankshaft with engine oil. or-dry sandpaper. Using light pressure, move both 2.
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IO080A IO101 5. Apply lightweight oil to the tappets; then install the NOTE: When installing the governor control shaft, tappets to the proper guides as noted during disas- position the shaft so the flat end (A) of the shaft is sembly.
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9. Secure the crankcase side cover to the crankcase 14. Install the air shroud to the cylinder head and secure with the cap screws. Tighten to 16 ft-lb using the fol- the shroud with cap screw. Tighten to 96 in.-lb. lowing pattern.
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IO097A IO100A 23. Install the throttle cable mounting bracket and secure NOTE: Route the stator harness through the slot in the bracket with two cap screws to the crankcase. the crankcase above the flywheel. Tighten to 120 in.-lb. 19. With the flywheel key in the crankshaft, install the flywheel and starter pulley;...
IO065A IO064A 28. Install the retaining plate and fitting; then secure the NOTE: When securing the governor control shaft air cleaner cover to the air cleaner case with the two (A), turn it clockwise until it stops; then tighten the screws.
9. Install the tie rods on the steering post; then secure with lock nuts (threads coated with green Loctite #609) and washers. Tighten to 20 ft-lb. 10. Place the steering post in position in the lower steer- ing post bearing and on the steering post support. IO106A 14.
4. Mark the ratchet arms (E) for assembling purposes; then remove the ratchets and account for the friction Recoil Starter spring (F). NOTE: The ratchet arms must be installed in their respective positions. 5. Slowly remove the reel. Account for the spiral spring (G).
REMOVING Fuel System NOTE: Before removing the carburetor, be sure the gas tank shut-off valve is in the OFF position. 1. Remove the screws securing the air cleaner cover to the air cleaner case and account for the filter and This section has been organized for servicing the fuel retaining plate.
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CLEANING CAUTION DO NOT place any non-metallic components in parts- cleaning solvent or carburetor cleaner because damage or deterioration will result. 1. Place all metallic components in a wire basket and submerge in carburetor cleaner. 2. Soak for approximately 30 minutes; then rinse with fresh parts-cleaning solvent.
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1. Install the nozzle (H) and main jet (G) into the carbu- retor tower. 2. Place the needle jet assembly (F) and the float (E) into position and secure to the carburetor body with the float pin (D). 3. Secure the float chamber w/rubber gasket to the car- buretor with the cap screw (C).
0744-922 A979 2. Pull all slack from the throttle cable wire and exert 2. Disconnect the throttle cable from the lever; then slight tension on the wire. slide the cable out of the lever. 3. Tighten the throttle cable jam nuts. ! WARNING DO NOT operate the snowmobile when any component in the throttle system is damaged, frayed, kinked, worn,...
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NOTE: Note the location of the cable tie for assem- 2. Seat the cable drum into the throttle lever recess; then secure the throttle lever to the throttle control bly. with a pin and C-clip. 5. Rotate the throttle cable lever of the governor control arm to the wide-open position and route the cable end out of the arm;...
As the flywheel turns faster, the primary current increases, and the terminal voltage of the circuit consist- Electrical System ing of the resistor (R) and the transistor (TR1) increases. This increases the working voltage at the connection of the series circuit (r1 + r2) connected in parallel to the pri- mary circuit.
Testing Ignition Switches 1. Disconnect the engine wires from the main wiring harness. 2. At the main wiring harness engine connector, connect the red tester lead to the violet wire; then connect the black tester lead to the engine ground (brown wire). 3.
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1. Open the hood; then disconnect the handlebar warmer two-wire connector. 2. Connect one ohmmeter lead to the green/white lead; then connect the other ohmmeter lead to the yellow lead. YM-145 3. With the handwarmer toggle in the ON position, con- nect one ohmmeter lead to pin and the other ohmme- ter lead to pin.
Drive System Drive Chain and Sprockets REMOVING 1. Remove the self-tapping screws securing the front clutch shield and rear sprocket cover; then remove from the engine compartment. Note the position of IO112A the hood cable. 6. Secure the centrifugal clutch with a pair of channel- lock pliers at the outer clutch collar;...
6. Inspect the driveshaft sprockets for wear or damage. 6. Place the muffler into position in the engine com- partment; then press down on the muffler and posi- INSTALLING tion the flange onto the engine exhaust studs. Secure with two nuts and the hold-down spring. 1.
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INSTALLING 1. Spacer 2. Carriage Bolt 3. Bearing 4. Track Drive Assy 5. Drive Sprockets 6. Driveshaft 7. Key 8. Chain Sprocket 9. Lock Nut 10. Cap Screw 11. Washer 12. Chain IO115A 5. Remove the four lock nuts securing the drive 742-425A sprocket bearings to the tunnel;...
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Excessive wear to the idler wheels, drive lugs, and track will occur if the track is improperly aligned. Arctic Cat recommends that the track alignment be checked once a week or whenever the track tension is adjusted.
2. Position the tips of the skis against a wall; then using 3. After proper track alignment is obtained, tighten both a shielded safety stand, raise the rear of the snowmo- the adjusting bolt jam nut and the idler wheel cap bile off the floor making sure the track is free to screw securely.
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4. Remove the brake band from the engine compart- ment. 5. Remove the C-clip securing the brake lever pin in the brake housing; then remove the pin and lever. A999 A998 6. Disconnect the brake cable from the lever; then slide the brake cable out of the lever.
3. If travel distance is not as specified, adjust the brake. ADJUSTING BRAKE LEVER TRAVEL A005 6. Secure the brake cable to the steering post with a cable tie; then install the handlebar pad. 735-457A 7. Install the hood cable and the front clutch shield. 1.
This section has been organized so each procedure can be completed individually and efficiently. The technician Rear Suspension should use discretion and sound judgment when removing and installing components. GENERAL INFORMATION Removing Skid Frame Quick acceleration and the ability to go through the turns with power are the most important handling qualities.
NOTE: A wear strip can be removed and installed without removing the skid frame. To do this, remove the machine screw and lock nut securing the wear strip at the front of the slide rail; then align the wear strip with openings (windows) in the track and drive it rearward off the slide rail.
INSPECTING 1. Inspect all rear arm weldments for cracks or unusual bends. 2. Inspect all tubing for cracks or unusual bends. 3. Inspect the axles for wear or damage. 4. Inspect the upper and lower bearings for wear or damage. 5.
ASSEMBLING 1. In order, slide the axle through the rear axle housing; Slide Rail then place a spacer on the axle. Slide the axle through the opposite axle housing. 2. Place the adjuster bushings on the axle (on the out- side of each axle housing).
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AO160 0743-189 3. Remove the cap screw securing the rear suspension INSTALLING arm to the support bracket. 1. Install the rear axle housing and adjuster bushing; 4. Remove the cap screws and lock nuts securing the then secure with cap screws and lock nuts. Tighten to rear suspension arm support bracket.
6. Place the snowmobile in the upright position. 7. Securely tighten all mounting hardware (from steps 3 and 4) to 20 ft-lb. 8. Check track tension; adjust as necessary (see Track and Driveshaft section). Steering and Body Steering Post AO160 6.
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7. Using a solvent, clean the old adhesive from the han- dlebar. 8. Loosen the screw securing the emergency stop switch to the handlebar; then remove the stop switch. 9. Remove the two cap screws and lock nuts securing the upper steering post bearing retainer; then remove the retainer and bearing.
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INSTALLING A026 NOTE: Check all fasteners to ensure they are tight. Turn the handlebar full-left and full-right several times to ensure free movement. 6. Apply Handlebar Adhesive to the bore of the handle- 1. Steering Post 11. Pad Cover 22.
2. Center the wear bar studs in the holes and install the lock nuts. Tighten lock nuts securely. Tie Rods REMOVING AND DISASSEMBLING 1. Remove the tie rod from the spindle. ZJ296A NOTE: The ball joint must be installed on the bot- tom side of the spindle arm.
IO119A IO119B 5. Remove the two cap screws and lock nuts securing 2. Place the tie-rod ball joint into position on the bottom the spindle to the suspension arms. Account for all side of the spindle arm and secure with a lock nut mounting hardware.
2. Measure the distances to the inside edges of the skis in two places. Make sure the measurements are taken behind the spindle mount and ahead of the spindle mount. AO167 4. Remove the lock nuts securing the A-arms to the chassis;...
INSTALLING 2. Remove the two cap screws securing the belly pan to the front end; then account for washers and lock washers. 1. Upper A-Arm 2. Lower A-Arm 3. Axle 4. Axle 5. Axle 6. Cap Screw 7. Cap Screw 8.
2. Inspect the two belly pan threaded bosses and ensure 5. Remove the knot at the handle and remove the han- they are in good shape. dle; then thread the rope through the bushing in the console. INSTALLING 6. Turn the gas tank shut-off valve to the CLOSED 1.
5. Untie the slip-knot at the starter case and allow it to slowly rewind into the case. 6. Slide the choke cable through the console and secure with two lock nuts; then using a screw (coated with blue Loctite #243), secure the choke knob to the end of the cable.
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