what does it mean when a viscous fan doesn't spin when the engine is at full temperature?

my BMW's been dropping some oil lately, and i opened the bonnet when i got home from work today to have a look, the fan wasn't spinning at all, and didn't move when i revved the engine a bit, yet the car stays at perfect temperature. i was just about to touch the fan to try and start it moving, decided against that that idea though

is this normal?

Not normal, it must have leaked its fluid.

They should always have a bit of resistance even when cold, but if it does not overheat then best to remove altogether incase the bearings fail and it causes a breakdown.

I would guess with BMW prices an electric replacement is in order.

ah bollocks.

if its not one thing its another...

cheers mate, I know a few bmw breakers, might be able to sort a replacement for a good price. I got a door for my old E30 for £40 including next day delivery, so fan should be ok

remedy = take of the powerrobbing fan and install an electrical one.

most of the times that is the cheaper sollution

grtz Thomas

power robbing you say?
200bhp is enough for a young lad like me. I'm surprised i got insured.

had a look this morning, the fan shroud was a bit loose and touching the fan, clipped it back in place and the fan turns, so i'm not worried about the bearings now, but i'm not sure how these things work anyway.

how do they work?