How does clutch fan work

But even if it rotates three or fewer times the clutch could still be bad. You need to do more tests. In these vehicles, the silicone fluid doesn't drain back overnight, so the fan may barely spin on a cold engine.

It could take a brief drive to get it to declutch. If your fan clutch is not operating the way it should, it's likely due to a fluid leak or a bad thermostatic spring or valve.

When a leak occurs, it's at the bearing seal, at the center rear of the clutch. Run your finger around the joint and if you get a big dollop of black goo, that's silicone fluid that has leaked from the housing. Replace the fan clutch. A light smear of silicone fluid could be normal seepage--no seal is perfect. Obviously, if a substantial amount of fluid is missing, the clutch won't spin as fast as it should. As for the other potential culprit, most failing thermostatic springs open the valve too soon.

On the other hand, failed valves that stick closed result in low fan speeds and little cooling. Let's say spinning the fan didn't reveal a problem, there's no leak and you think the spring is okay. You could still have a bad valve. Here's how to find out. You can't use an infrared thermometer because it will read the temperature of a nearby surface, which could be very different from the air temperature. Find a joint in the fan shroud with enough flex to let you insert the probe without getting it in the path of the fan.

If necessary drill a small hole in the shroud. Run the engine at fast idle. Check the engine temperature gauge or your scan tool. If it's a hot day, the coolant temp will rise. Note: Don't try to take an instant reading. A conventional thermometer, even the probe type, takes at least a couple of minutes to stabilize. If you don't have a thermometer, you can hear what you need to know. Listen to the fan noise with the engine cold, then warm up the engine.

Watch the temp gauge. As the coolant gets hot, fan noise should increase to a roar and the fan should spin a lot faster. If not, you'll need a new clutch. Don't let the vehicle overheat. Use a probe-type thermometer to check the temperature of the air moving through the radiator. The fan clutch is design with either an electronic controlled activation device or a temperature sensitive spring at the front of the clutch to tell the clutch when to turn on and engage to the input shaft.

When the clutch engages the fan blade starts to operate pulling air though the radiator to cool the engine down. Most fan clutches are filled with silicone grease which will leak out when the fan clutch goes bad.

Because the fan clutch is not used when the engine is cool it will disengage which helps increase gas mileage and engine performance. A main housing, input shaft, input shaft bearings and a clutch shoe is used to make up the fan clutch which then bolts to the fan blade and water pump. A cooling fan can turn either clockwise or counterclockwise depending on the manufacturers design.

Are you saying that, if you grab a fin and try to spin the fan but it stops very nearly as soon as you let go of it, the clutch is bad? It should stop spinning relatively quickly—but if, after the engine has stopped, it just spins and spins, then it points to a problem with your fan clutch. Is it ok to use a heavy duty fan clutch when a standard is normally used or came from the factory?

So my question is. I have changed out my fan clutch 3 times already and my car is still over heating? Changed it out again this past weekend stopped over heating but now less power? Then this morning started up had the power it should but once again started to over heat!! Please help me!! What is wrong with my car?? Its a Oldsmobile bravada. Do you think there could be another reason your engine is overheating? What is the age of the coolant?

Has the radiator been flushed within the last 4 years? Was the thermostat replaced in the last 4 years? What is the age of the water pump? Did you prove the water pump is functioning the way it should? How about hoses? What are their ages? Did you ever see an old hose collapse? You have too many questions and not enough answers.

Do to need to have a belt driven pulley when running a spring actuated fan clutch and how does the water circulate around the motor without one. Yes, a spring actuated fan clutch would only be used on a vehicle with a belt driven pulley. On vehicles without a belt driven pulley, the water would be circulated either by a water pump driven by the timing belt, or by an electrical water pump. Either way, the cooling fan in such vehicles would be electrical. With a thermal clutch fan if you remove the spring the fan will stay engaged!

I had to do that to a number of trucks to keep them running for the day R. I live in Cali. Your email address will not be published. Your Website.