The cooling fan clutch plays a pivotal part in your vehicle's cooling system. It helps power up the fan blade when your engine gets too hot and it turns it off when not needed to save power. Anytime your engine gets too hot, the clutch will engage the fan blade assembly so it blows air at your radiator to help it cool down. Once your engine gets to a normal operating temperature, it will disengage from the fan to help conserve power. Just like any other part on your vehicle, the fan clutch is prone to fail due to normal wear and tear and should be replaced as soon as possible to avoid any additional damage to the engine.
Some symptoms of a bad cooling fan clutch include:
- Overheating when idle or in heavy traffic
- Fan blade assembly is always running
- Grinding noise due to a worn bearing
- Poor A/C performance at low speeds
An overheating engine can cause the head gasket to crack or the cylinders to warp, which will be a more expensive fix than the cooling fan clutch. If the clutch is stuck, always in the engaged position you will notice a more sluggish ride because the part is taking power from the engine in order to operate. It is recommended that the water pump also be replaced if you are changing the fan clutch, and vice versa.
There are 2 basic types of cooling fan clutch
, thermal and non-thermal. A thermal one works similar to a thermostat in that is uses a bi-metal thermal spring to engage or disengage the cooling fan blade. When it is hot, the spring will expand, opening a passage and allowing a silicone base fluid inside the part to enter a reservoir in the clutch which causes it to engage the fan. When it gets cold, the spring will retract, closing the passage, which will cause the part to disengage the fan. A non-thermal one works based on speed of the water pump shaft and not based on temperature. At idle or low speeds it will turn the fan at a 1:1 ratio. At high speeds it will basically lets the fan free-wheel.
Replacing your cooling fan clutch is a pretty straight forward process. It will likely require the removal of the fan shroud which will only be held on by a few bolts. Next step will be to remove the fan blade/fan assembly. They will be held on by either a few bolts or one large nut. If you have the style with the large nut, it might require the use of a special tool, which can be purchased or rented at your local auto parts store. Then just set the fan blade/clutch on a table and unscrew a few more bolts to remove the fan clutch from the fan blade. Then just repeat the process backwards using the new cooling fan clutch.
If you have confirmed that your overheating problem is caused by a bad cooling fan clutch, be sure to replace it as soon as possible with a new one from Car Parts Discount. Save your engine, and your wallet, from a more expensive fix that can occur from driving with a bad cooling fan clutch.