How to Remove Clutch Plates From a Yamaha Warrior ATV

Yamaha's Warrior 350 series of all-terrain vehicles use a friction-based clutch to transfer engine power to the transmission and rear wheels. A series of fiber and steel plates are held tightly together within the clutch during normal operation. These plates separate when the clutch lever is pulled in, isolating the engine from the transmission. A slipping clutch is a common problem, which prevents the clutch plates from maintaining their grip against each other. This is often caused by wear and can be remedied by replacing the clutch plates as a set.

Things You'll Need

• Oil catch pan
• 22 mm socket
• Socket wrench
• Torque wrench
• 12 mm socket
• Phillips screwdriver
• Needle-nose pliers
• 12 mm open-end wrench
• 10 mm socket
• Flat screwdriver
• Rotor holder tool
• 7 fiber friction plates
• 6 steel clutch plates

Instructions

Removal and Replacement

1. Park the ATV on a level surface and let the engine cool for a minimum of 30 minutes.

2. Unscrew the oil cap from the top of the right crankcase cover. Place an oil catch pan below the engine, then unscrew the drain plug from the bottom of the engine crankcase, using a 22 mm socket and a socket wrench. Let the oil drain until the flow of oil reduces to a light drip. Screw the drain plug into the crankcase and tighten it to 31 foot-pounds, using a torque wrench.

3. Remove the right foot guard and the right foot peg with the rear brake pedal, using a 12 mm socket and a Phillips screwdriver. Pull the return spring off the rear of the brake pedal, using needle-nose pliers.

4. Loosen the clutch cable lower adjuster lock nut, located above the right crankcase cover near the exhaust pipe, using a 12 mm open-end wrench. Turn the cable adjuster clockwise by hand to loosen the clutch cable, then pull the cable end out of the clutch release arm on the top of the crankcase cover. Remove the right crankcase cover and gasket, using a 10 mm socket.

5. Remove all five spring bolts from the clutch pressure plate, located at the center of the clutch assembly, using a 10 mm socket. Pull the clutch pressure plate, along with its central bearing and the clutch push rod, off the clutch assembly. Pull the clutch springs off the spring towers cast into clutch boss plate at the center of the clutch assembly.

6. Bend the lock washer's tabs away from the large nut at the center of the clutch boss plate, using a flat screwdriver. Hold the clutch assembly in place, using a rotor holder tool. Unscrew the nut, using a 27 mm socket. Pull the clutch boss plate out of the clutch assembly.

7. Pull all 13 clutch plates out of the clutch assembly. Remove the pair of spring plates from the clutch plate stack.

8. Soak the new fiber friction plates and steel clutch plates in SAE 10W-30 motorcycle-grade engine oil for at minimum of one hour. Note that two of the fiber friction plates are thinner than the other five plates.

9. Slide a thicker fiber friction plate into the clutch assembly, followed by a steel clutch plate, a thick fiber friction plate and another steel clutch plate. Place a spring plate into the clutch assembly, followed by a thin friction plate, a steel clutch plate, the remaining thin friction plate and the second spring plate. Place the remaining friction and steel clutch plates into the clutch assembly, alternating between friction and steel plates.

10. Push the clutch boss plate over the clutch plates, then slide a new lock washer onto the clutch assembly's central shaft. Screw the clutch nut into place. Hold the clutch assembly in place and tighten the clutch nut to 58 foot-pounds.

11. Push the clutch springs onto the clutch boss plate spring towers, followed by the pressure plate. Screw the clutch spring bolts into place and tighten the bolts to 7.2 foot-pounds. Push the clutch push rod and bearing into the center of the pressure plate if either piece was removed.

12. Reinstall the right crankcase cover and gasket onto the engine. Tighten the cover bolts to 7.6 foot-pounds. Slip the clutch cable end into the clutch release lever, then turn the lower cable adjuster counterclockwise by hand to tighten the clutch cable. Tighten the cable adjuster lock nut.

13. Reinstall the right foot peg and foot guard onto the ATV. Tighten the foot peg and foot guard bolts to 40 foot-pounds. Hook the return spring onto the rear of the brake pedal.

14. Fill the engine with 2.25 quarts of SAE 10W-30 motorcycle-grade engine oil, then screw the oil cap into place. Start the engine and let if idle in place for three minutes, then stop the engine and let the oil settle for five minutes. Check the oil level, using the dipstick attached to the oil cap. Add one to two ounces of engine oil if the oil level is below the dipstick's lower mark. Screw the dipstick and oil cap into place if the oil level is between the upper and lower marks.

Tips & Warnings

• Do not reuse the engine oil after draining it from the ATV's engine. Used oil can contain debris that will harm the engine and transmission.

• Store used engine oil in a sealed container, away from the reach of children or animals, until it can be taken to a Yamaha repair facility or an oil recycling center for disposal.

References

• Yamaha YFM350X Service Manual; Yamaha Motor Corporation
• Yamaha YFM350XP Supplemental Service Manual; Yamaha Motor Corporation