Clutch Not Working

Easy step by step guide on how to fix an automotive transmission clutch assembly that is not working, steps are presented in order of popularity and pertains to most vehicles.

Difficulty Scale: 5 of 10

Tools and Supplies

  • Flashlight
  • Wrench set
  • Socket set
  • Appropriate replacement parts
  • Protective eye wear and gloves
Begin with the vehicle on level ground, in park with the engine "OFF". Also apply the parking brake.

Automotive Clutch
Step 1 - Begin by checking the fluid level of the primary cylinder, if the fluid is low or out completely, the system is leaking and repair is required, inspect the clutch primary and secondary cylinders for leakage at the dust boot of input rods. (Note: Inspect under the dash toward the rear of the clutch master where its common for a leak to occur.) (Note: Some vehicles utilize the brake master cylinder fluid reservoir for the primary clutch cylinder.)

Add Clutch Fluid
Step 2
- The clutch disc is made of an asbestos compound much like a brake pad, when this material wears it loses pressure against the pressure plate and flywheel which allows slippage, the clutch disc is worn out and replacement is needed. (Note: If engine leak are present it can contaminate the clutch disc causing slippage.)

Clutch Disc Wear
Step 3 - If when the clutch pedal is depressed a squealing noise is observed, but quiet when the clutch is not disengaged the throw out bearing has failed.

Failed Throw Out Bearing
Step 4
- If a clutch primary cylinder fails it will not push fluid to the secondary cylinder, in turn not disengaging the clutch disc, to check for this condition have a helper depress the clutch pedal while watching the secondary cylinder, if no movement is observed. the primary cylinder has failed.

Press Down Clutch Pedal
Step 5 - The clutch disc could be completely broken, not allowing the disc to "slip" within the pressure plate and flywheel, the transmission must be removed and the clutch assembly dissembled to inspect for this condition. Visit - Clutch Replacement

Remove Transmission
Step 6
- The transmission utilizes an input shaft to drive the drive gears inside the transmission, if this input shaft or gear fails, it will allow the gear shifter to move, but not output power.

Transmission Input Shaft
Step 7 - When a clutch control cable fails it will not actuate the clutch assembly causing the transmission to not go into gear, if the pedal is depressed with little resistance inspect the clutch cable for failure.

Helpful Information

 If the vehicle is running and a whirring sound is heard form the transmission, then it goes away when the clutch is depressed, the transmission input shaft bearing has failed.

Best Practices

  • When replacing a clutch disc, also replace the pressure plate throw out and pilot bearings if equipped.
  • Resurface flywheel
  • Once the flywheel has been removed inspect the engine rear main seal.
  • Always lubricate the throw out bearing slide surface to ensure proper operation.
Article first published