1991 240sx: anybody experienced with the stock fan clutch?

[vancouverbc]

my current fan clutch is seized up and only rotates 6 inches when I spin it. I bought a used clutch to replace it but it seems seized too. I dont have a fan to attach to it . Without the fan blade, it does not spin. I'm trying to figure out if I should just buy a new one?

http://ca.youtube.com/watch?v=Eva1fpxEm_c
Modified by vancouverbc at 8:56 PM 12/15/2008

[livinglegend2100]

you should pick up a set of electic fans from the junkyard or wherever and get rid of your clutch fan.

[AZ89two4Tsx]

^ I hate the clutch fan. It noisy, ugly, and in the way.

[OM3GA]

IT's most likely not "seized" its thermostatic, you are supposed to be able to turn it but feel tension. Thermal fan clutches have a temperature-sensitive bimetal coil spring on the front that reacts to temperature changes. When the air coming through the radiator is hot, the spring expands and opens an internal valve that reduces clutch slippage. This causes the fan to spin faster for increased cooling. As the air cools, the spring contracts and closes the valve. This increases the amount of clutch slippage, allowing the fan to slow down and decrease cooling.

Spin the clutch fan when the car is cold, It should spin less than one full rotation any more than that and its definitely bad or just really worn. Newer ones you can spin them and they rotate maybe 1/3 turn, thats how mine is since i just bought a new one maybe 7000 miles ago. Sounds like you dont have much to worry about with it Try it out and see how it works.

With it off the car and you rotating it it should have a decent amount of tension but not enough to have to really work to get it to rotate. Try it out and hopefully all goes well!

[Ghast]

First of all isn't youtube WONDERFUL for things like this? I think it is.

I always thought the fan was supposed to have a little bit of play but not as if its like a bearing or anything. Going to go spin mine really fast.

*10 minutes and a glass of ovaltine later*

Ok well i spun mine and it did the same thing as yours.

Only it spun a little more, because of the area+weight of the fan.

I am not exactly sure how the stock fan works but my Theory of operations would be that it has a little bit of play because that would be a little bit hard on the system if it was to be powering the entire mass of the fan at all times, mainly on start up and slow down. and i guess at high speed or maximum speed is when the "clutch" inside of it would kick in.

But i dunno, i don't think the one u have is broken.

Does anyone have a good video or article to read on cooling fans? like any proof that the electric fans cool as well as the stock clutch fans? because LOOKING at it the electrical fans don't look at all like they would be as powerful as a stock clutch fan.

This was probably not helpful but if yours is broken then mine is broken and you are not alone in the "broken clutch fan boat"

Good Luck.

One Love,

Ghasty

[the converted]

Here's a decent article. http://news.carjunky.com/how_s...shtml

The nice thing with electric fans is that they are not engine speed dependent, so you can get their full flow idling at a stop light. Once your over ~20mph the air speed forces more air through than the fans would anyway.

[livinglegend2100]

Here's a decent article. http://news.carjunky.com/how_s...shtml

The nice thing with electric fans is that they are not engine speed dependent, so you can get their full flow idling at a stop light. Once your over ~20mph the air speed forces more air through than the fans would anyway.

got any pics of that lotus?? /threadjack

[the converted]

I have pictures of miscelanious bits and peices that will one day become a Lotus.

[vancouverbc]

IT's most likely not "seized" its thermostatic, you are supposed to be able to turn it but feel tension. Thermal fan clutches have a temperature-sensitive bimetal coil spring on the front that reacts to temperature changes. When the air coming through the radiator is hot, the spring expands and opens an internal valve that reduces clutch slippage. This causes the fan to spin faster for increased cooling. As the air cools, the spring contracts and closes the valve. This increases the amount of clutch slippage, allowing the fan to slow down and decrease cooling.

Spin the clutch fan when the car is cold, It should spin less than one full rotation any more than that and its definitely bad or just really worn. Newer ones you can spin them and they rotate maybe 1/3 turn, thats how mine is since i just bought a new one maybe 7000 miles ago. Sounds like you dont have much to worry about with it Try it out and see how it works.

With it off the car and you rotating it it should have a decent amount of tension but not enough to have to really work to get it to rotate. Try it out and hopefully all goes well!

Thanks. That clears things up. I have a really bad belt squeal at low rpm's and when I turn on the interior heater so I assumed it was the fan clutch because it only turns 6 inches when cold. However, today, i spun the fan after I had been driving for half an hour and the fan spun about half way around. I'm assuming my existing and replacement fan clutch are fine. damn. I now have to figure out what is causing the darn belt squeal because it does not go away even after I have driven for long time.

[vancouverbc]

noticed that if i drive for half an hour and turn off engine. the fan will spin about half a turn for a few minutes until it cools down and then becomes stiff. some people say the fan should stop spinning when engine is cool during start up.