Does a fan clutch always spin?
Spin the fan. Electronic types might freewheel, but most fan clutches should spin with a little effort. If the fan spins more than three times, you may have a bad fan clutch.
When do you know it’s time to replace the fan clutch?
According to Hayden, here are some signs your fan clutch might need replaced: Fan spins excessively when engine is stopped (three or more times when hot engine is shut off). Poor A/C performance at idle or low vehicle speeds. Fan speed does not increase when engine is hot.
What is an electric fan clutch?
The fan clutch is a cooling system component that controls the operation of the engine cooling fans. While many newer vehicles now use electric cooling fans to keep the engine cool, many older vehicles used a mechanical fan clutch to control the fans.
What causes a car fan clutch to go bad?
Insufficient heat in winter is another common problem but caused by the opposite fan clutch failure. If the fan clutch seizes, it remains engaged all the time, cooling off the engine too much. Excess fan noise at high speed is caused by the same problem, a seized fan clutch.
How can you tell when a fan clutch is engaged?
You should be able to audibly detect when the fan clutch engages, with an accompanying rush of air. At idle, as engine temperature increases, a thermal fan clutch will engage at a certain temperature. Torque-limiting fan clutches will disengage at a certain engine speed. Alternatively, an optical tachometer can be used to measure fan speed.
What happens when you have a bad fan clutch?
A stuck fan clutch will cause excessive, unnecessary drag on the engine, which can cause a drop in power, acceleration, and fuel efficiency, sometimes to a quite noticeable degree. As the fan clutch is one of the main cooling system components, it is very important to the proper operation of the engine.
How does a torque limiting fan clutch work?
A torque-limiting fan clutch reacts to engine speed. A centrifugal valve opens to allow the flow of heavy silicone fluid, locking the fan blades to the pulley. At idle and low engine speeds, this fan clutch is fully engaged, gradually disengaging as engine speed increases.
What makes a fan spin with a cluthc?
With a fan cluthc your fan will rotate constantly regardless. The clutch engages and locks the blade to it so that it spins faster than normal the hotter that it gets. The only time that your fan will not spin is when the motor is off. It is a common misconception that the fan will only spin when the clutch engages. Click to expand…
What’s the difference between standard and heavy duty fan clutches?
Standard-Duty Thermal Fan Clutch: This design turns the fan at 60-70 percent of the water pump shaft speed when engaged, and 20-30 percent when disengaged. It’s made for fans with a lighter pitch. Heavy-Duty Thermal Fan Clutch: This fan style turns the fan at 70-90 percent of the shaft speed when engaged for increased cooling.