Troubleshooting a Noisy Fan Clutch
Sometimes the fan clutch in your car will start making squeaking and squealing noises. In this article we will tell you how to troubleshoot and make sure that the fan clutch is the problem and not something else in your automobile. If you start your car and turn on the air conditioner or heater and the noise is a scraping or squealing noise that goes away when you turn off the fan, it is probably the clutch. A noisy fan clutch can also be the culprit when your car is overheating.
The Clutch Is Moving
Watch the fan clutch while the engine is on, and if the clutch is moving on the shaft, this is a simple fix. Check the bolt and washer on the center and be sure that it is tight. If it is not tight, re-tighten the center bolt. If this doesn't help then change the space or the length of the shaft and this should take care of the problem.
The Pulley Bearing is Making Noise
If there are noises when the the pulley is going, take the bearing out and check it for burrs or see if it is rough. Check the belts and make sure that you are not overloading them and the bearing. If your bearings are overloaded you need to reduce the belt load. See your car manual for instructions on how to do this.
If the clutch is slipping and the car is overheating you need to remove the clutch and look at it. If it is discolored, then it has been slipping and needs to be replaced. You will hear the clutch slipping when you have the fan running and it will be making noises. The heating or cooling will also be interfered with by this slippage. If your air is running cold, then warm and then cold again, then you need to check to see if your clutch is slipping
Remove the clutch and check the race bearings (inner and outer) for damage. If you find damage or the key is too tight causing pressure on the inner bearings, you need to replace the clutch and bearings. If you replace the bearings you need to replace the clutch as well. You cannot just replace the races.
Checking the Clutch
After running your car, check the temperature of the clutch shaft where it mounts to make sure it is under 300 degrees. If it is too high then you have to replace the clutch. If your clutch is heating up the shaft it will cause the high temperature overload on the engine.
When the clutch is not engaged and you hear pinging or metallic noises your air gap is too close. You need to increase the air gap between the clutch and the mounting. Nothing is wrong with your clutch.