How a Transmission Clutch Works
When your car is stopped or coming to a stop the engine needs to be disconnected
from the transmission
or the engine will
stall. With
automatic transmission
vehicles a torque converter
is used to separate the two units, but with manual transmission vehicles a clutch
assembly is used to do the job. This clutch kit or unit is composed of a clutch
disc, pressure plate, throw out and pilot bearings. (Some front wheel drive vehicles
do not use a pilot bearing). Both types of vehicles use a
flywheel but are designed
a little differently. An automatic transmission has a lighter weight unit that the
torque converter bolts directly to and is sometimes referred to as a flex plate.
A manual transmission flywheel assembly is made heavier to help engine inertia and
to make shifting smoother. The clutch pressure place bolts to the flywheel trapping
the clutch disc in-between. The throw out bearing presses against the pressure plate
to engage and release the disc. The pilot bearing is mounted in the flywheel and
holds the input shaft for the transmission steady.
Clutch and Flywheel Assembly (Cut Away) Most clutch assemblies operate on the same principle; hold a clutch disc against a flywheel under pressure with the ability to release the pressure to allow the clutch disc to freewheel. The clutch disc is connected to the transmission using an input shaft to the transmission gears and then through to the drive shaft or axles.
Typical Fly Wheel Configuration When replacing the clutch assembly always resurface the flywheel clutch disc surface. As the clutch wears it can cause the flywheel surface to become un-even, much like a worn brake rotor. If a new clutch disc is installed on and old flywheel it can cause the clutch to not operate properly. If the flywheel is dual stepped (example shown) it must be machined the same way or the clutch clamping pressure will be incorrect causing the clutch to slip or not disengaged.
Typical Clutch Pressure Plate, Disc and Throw-out Bearing There are two different types of clutch activation methods. Some manufactures use a cable that is fastened to the clutch pedal and then to the clutch fork. While other manufacturers use a hydraulic clutch master cylinder that is connected to a slave cylinder which is positioned at the bell housing, also connecting to the clutch fork. When the clutch pedal is depressed it will force the clutch fork onto the pressure plate causing the pressure plate fingers to release the clutch disc. If further assistance is needed, our certified car repair technicians are ready to answer your car questions.
Typical Clutch Fork
Related Car Repair Information
Clutch and Flywheel Assembly (Cut Away) Most clutch assemblies operate on the same principle; hold a clutch disc against a flywheel under pressure with the ability to release the pressure to allow the clutch disc to freewheel. The clutch disc is connected to the transmission using an input shaft to the transmission gears and then through to the drive shaft or axles.
Typical Fly Wheel Configuration When replacing the clutch assembly always resurface the flywheel clutch disc surface. As the clutch wears it can cause the flywheel surface to become un-even, much like a worn brake rotor. If a new clutch disc is installed on and old flywheel it can cause the clutch to not operate properly. If the flywheel is dual stepped (example shown) it must be machined the same way or the clutch clamping pressure will be incorrect causing the clutch to slip or not disengaged.
Typical Clutch Pressure Plate, Disc and Throw-out Bearing There are two different types of clutch activation methods. Some manufactures use a cable that is fastened to the clutch pedal and then to the clutch fork. While other manufacturers use a hydraulic clutch master cylinder that is connected to a slave cylinder which is positioned at the bell housing, also connecting to the clutch fork. When the clutch pedal is depressed it will force the clutch fork onto the pressure plate causing the pressure plate fingers to release the clutch disc. If further assistance is needed, our certified car repair technicians are ready to answer your car questions.
Typical Clutch Fork
Related Car Repair Information