Description and testing of the clutch

Models with RT are equipped with a single-plate dry clutch with a diaphragm spring.

Components of a typical clutch assembly

The clutch is actuated by a hydraulic system.

When the clutch pedal is depressed, the hydraulic fluid (under pressure created by the clutch master cylinder) transmits power to the slave cylinder. Since the slave cylinder is connected to the clutch release fork, this fork brings the release bearing into contact with the petals of the pressure plate, disengaging the clutch disc.

The hydraulic system adjusts the clutch automatically, so no additional adjustment of the actuator or pedal is required unless you have replaced the clutch master cylinder and/or pushrod.

When working with instructions, sometimes problems may arise with terminology related to clutch components, as different manufacturers, auto parts store sellers, and car dealers call the same parts by different names. For example, the driven disk is also called the clutch disc and the friction disc; the slave cylinder is sometimes called the working cylinder, etc.

Examination

Components that are clearly damaged should be replaced, but for cases where the cause of system failure is not so obvious, here are some preliminary diagnostic checks.

1. The first step is to check the fluid level in the clutch master cylinder. If it is low, top up and recheck the clutch operation. If you have drained the master cylinder or serviced any of the hydraulic system components, bleed the system (see section Bleeding the hydraulic clutch system). If you have to top up too often, it is probably due to a fluid leak.

2. To check the clutch release timing, start the engine and let it run at normal idle speed with the transmission in neutral (clutch pedal up). Disengage the clutch (pedal down), wait a few seconds, then engage reverse gear. There should be no grinding noise. A grinding noise indicates a component failure, probably in the pressure plate or driven disc assembly.

3. To check that the clutch is fully disengaged, start the engine (apply the brake to stop the car from moving) and hold the clutch pedal approximately 1-2 cm above the floor. Shift the transmission from first gear to reverse and back several times. If the shifting is not smooth, then one of the components is faulty.

4. Inspect the clutch pedal bushing at the top of the pedal to ensure it is not worn or interfering with pedal travel.