Clutch: Description and Operation

Clutch System Description and Operation

Clutch Spin Down Time

Inspect the clutch spin down time as follows:

1. Apply the parking brake and block the vehicle wheels.
2. Shift the manual transmission into NEUTRAL.
3. Start the engine. Run the engine at idle speed.
4. Engage the clutch.
5. Disengage the clutch. Wait 9 seconds.
6. Shift the transmission into REVERSE.

Clutch Driving Members

The clutch driving members are 2 flat surfaces machined to a smooth finish. They include the following:

* The rear face of the engine flywheel
* The front face of the clutch pressure plate

Clutch Driven Members

The driven member is the clutch driven plate. The clutch driven plate has a splined hub. The splined hub slides lengthwise along the splines of the input shaft. The splined hub drives the input shaft through these same splines. The driving and driven members are held together with a spring pressure. This pressure is exerted by a diaphragm spring in the clutch cover.

Hydraulic Clutch Fluid

Notice: Do not use mineral or paraffin-base oil in the clutch hydraulic system. These fluids may damage the rubber parts in the cylinders.

Hydraulic Clutch Operating Members

The clutch system consists of the following components:

* A master cylinder with a remote reservoir and with a hose assembly
* 2 switches
* An actuator cylinder
* The pressure plate
* The clutch cover
* The diaphragm spring
* The clutch disc
* The torsional springs

With the depression of the clutch pedal, the clutch master cylinder becomes pressurized from the force of the push rod into the master cylinder. This push rod motion forces hydraulic fluid through the hose assembly from the master cylinder to the actuator cylinder. The actuator cylinder then pushes the release bearing into the diaphragm spring to disengage the clutch. A hole in the cowl panel accommodates the master cylinder. A quick connect coupling attaches the hose assembly to the actuator cylinder. The actuator cylinder is inside the transmission and on the input bearing retainer. The master cylinder and hose assembly can be replaced without having to gain access to the clutch system internal components; simply disengage/engage the quick connect coupling mounted through the transmission housing. No adjustments to the clutch system are necessary. As the clutch wears, the fluid level in the clutch reservoir changes to compensate for clutch wear. A new system has fluid in the reservoir. The electrical switches on the clutch pedal/bracket assembly have 2 functions. One function is a clutch interlock, ensuring the engine does not start unless the clutch pedal is positioned on the floor. The second function is to cut off the cruise control system, if equipped, when the clutch pedal is pushed downward. Some systems may have a clutch pedal assist spring. This reduces driver fatigue during stop and go traffic.