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Within each vehicle there are many “pressure points,” where components that operate independently of each other need to engage. One of those locations is occupied by the flywheel/clutch mechanism.



What is a Clutch Flywheel?

For a vehicle to move, the engine must produce power and the transmission must deliver that power to the road wheels. Despite that you’d have to have some way of starting and stopping the vehicle, this would be enough to propel it in certain conditions and at a set speed. However, the driver must adjust the speed according to elevation or obstacles and as such needs a gearbox to achieve this variation.

The clutch mechanism enables instructions given by the driver to be converted into a variety of different speeds and crucial to the clutch mechanism is the flywheel, which is a heavy-duty disc that is mounted on the back of the engine and spins vigorously when the motor is running. In certain circumstances, it will interact with the gearbox and the rest of the clutch mechanism, to transfer power.

How Does a Clutch Flywheel Work?

When the engine is running but the car is not moving, the flywheel is directly connected to the clutch plate, which is another component that is bolted on to a splined shaft. When the driver is ready to engage gears, the gearbox and transmission must be separated from the engine and this is achieved by depressing a lever which is operated by the pedal. When this happens, the clutch disc and associated pressure plate move along the splined shaft to disconnect everything and when the driver eases pressure on the clutch pedal, the disc and plate once again meet the flywheel. The engine is now able to propel the car forward according to the specific gear ratio the driver has selected from within the gearbox. The flywheel is, in turn, mounted to a small bearing that is designed to match up with the gearbox input shaft, so that it can rotate effectively with the clutch assembly at certain stages.

How Is a Clutch Flywheel Made?

A typical flywheel is made from premium grade iron and dynamically balanced during manufacturer so that it can withstand vibrational forces and perform effectively over its lifetime. In some circumstances it is possible to replace an original flywheel with a lightweight version made of aluminum, but this is more common in racing applications than road use.

How Does a Clutch Flywheel Fail?

  • Pilot bearing break down
  • Dowel pins become dislodged
  • Surface may become damaged

What Are the Symptoms of Failure?

  • Inability to engage gear
  • “slippage” between gears
  • Burning smell
  • Excessive vibration

What Are the Consequences of Failure?

  • Excessive wear and tear on the vehicle’s transmission
  • Inability to move the car

The clutch and flywheel are designed to be able to put up with a considerable amount of vibration and engage many thousands of times during a typical lifetime. However, as in the case of other mechanical components, they will wear out over time.

If you have questions or concerns about Clutch Flywheels or any of your vehicle’s components, come into your local Pep Boys where we can answer any question, help you find any part, or perform any vehicle service you might need.