how do i know if my fan clutch is bad.? with engine off i can spin the fan freely, engine running at idle and rpms the fan turns with the speed of the motor. I have searched the forum and can only find threads on bad cooling systems, i just want to find out if my fan needs replacing

 

You should have some resistance when turning the fan by hand when the engine is cold. When starting the engine when cold, the fan clutch will make a louder noise because the fluid oil inside is cold. If it is bad, you will notice higher temps when stopped or driving a slower speeds. When running at higher speeds, the fan clutch doesn't really play a role. They are not available new.

 

Here's a video where I test mine cold and hot

https://www.rx7club.com/1st-generati.../#post12436191

 

toruki, my fan is full speed whenever the engine is running, it spins same speed as the Eshaft, i can stand back by the drivers compartment and its like a tornado blowing at me and this is all less than 2500 rpms. as the engine speeds up so does the fan and causes quite a wind blowing effect as i have no hood on right now

 

Does the tornado change after say 5-10 minutes? I've never seen one stuck in cold mode.

 

no i ran it for one 30 min cycle and the whole time the fan was full bore with the speed of the motor

 

Sounds like it's time for a good fan clutch.

 

Are there any aftermarket fan clutches that will work

 

There aren't. Buying a used one is iffy. Since yours went bad in the locked (cold) position it would be safe to run but noisy. The way I test my spares is to see if they have resistance when off the car. Given your experience, the only way I would test one now s on the car.

You can always go electric. Just make sure to include a shroud.

 

ok, suppose ill just run it the way it is for now. at least it will not overheat easily, also can i change the location of the coolant temp sensor to the position on the back of the water pump neck where the sensor is to operate the choke? would like a better sensor? also what is your experience with changing the oil pressure sensor to mechanical? good idea or bad to have hot oil in the passenger compartment or do i just change out the factory gauge and sensor for an aftermarket one that is better?

 

You could swap the water pump housing sensor to an aftermarket one and go with an aftermarket gauge. You will lose your choke and have to run that new wire to the new gauge.

Another option is to get an adapter sleeve for the upper water pump hose that has a 1/8 NPT bung to run a water temp gauge. Not sure which diameter is needed.





You can also replace the rear iron oil temp sensor to an aftermarket sensor and run a new electric oil temp gauge.

 

@Paulieboy72 did you ever sort out your fan clutch always matching engine speed?
I have the same exact issue, and replaced the fan clutch with another one from a friends parts bin, and still have the same issue. Is there anything else that can lock up the fan clutch such as a belt or water pump?

 

No. There is no fix other than finding a fan clutch that is not locked up or switch to an electeic cooling fan setup. If your clutch is semilocked up but spins with motor that is better than it not spinning, your just going to lise sone HP

 

Got it, thank you. Did you end up keeping the fan clutch or going electric?

 

You can refill the clutch fluid, it’s tedious at best, but for me, I wanted originality.

mine works awesome now!