viscous clutch always engaged
 

Hi Folks.

Yesterday I changed my watercooler and since today my fan squeals some minutes when engine is still cold. So I noticed that the fiscous clutch of my fan is always engaged and the fan pulls full air even if cold. So can this result in a problem after some time or is it already and can it be fixed or should I replace the fan?

thanks,

Harry

Did you tighten the belt enough?

I don't believe the clutch ever fully disengages (as in the fan sits still). It's more of a "degrees of engagement." Mine's pretty stiff even when cold, and tightens up more as it heats up. Doesn't bother me - I'd rather it stiffen up than not turn my fan.

If it really bothers you, just put an efan on, but as long as it's turning the fan, I wouldn't mess with it.

-=Russ=-

I know the fan never completely stops. But if the clutch is cold the fan should be easily stoppable (and was before). Now it always pulls strong - not good at higher RPMs I guess.

Harry

start looking for a new one..means that it going out...if it is always ON then it will wear the water pump out very fast....but it coudl break and alway be OFF then you can overheat...either way is not good...get a new one and not a used one SOON

If the clutch is cold, it should be harder to stop. When the clutch heats up, it spins more freely.

ok. gonna sacrifice my fingers once more :-)

Uh... care to rethink that? The idea is that when the engine is cool, the clutch is disengaged and the engine can turn without the fan turning much. As the engine heats up, the clutch will tighten, and the fan will turn with the engine & cool it.

For people with a properly working clutch: When the engine is cold, how far will the fan spin with a good flick? I don't get more than 1/3 turn even stone cold.

-=Russ=-

The stock S4 fan clutch pull some all the time, and gradually increases it's bite as the radiator heats up.
The S5 fan clutch is more on/off, with a very light pull when cold.
Some aftermarket replacement S4 clutches work like the S5's.
I bought one for my 87 & thought it was broken, but no, it was better.

The big deal is the torque limit.
The hot engine fan RPM should go up with engine RPM to almost 4K.
If it slips at 2500, it's worn out.