noisy fan belt?

[skippy]

can any one help me?

I have a noisy fan belt i have done the following

changed fan belt
cleaned all the v's on all pulley's
changed both tension and idle pulley's
tried reversing the belt

it seems to be coming from the crank pulley?
if you put dry lube it goes away for a minute
if you put belt grip it gets worse
if you put degreaser on it the noise goes for a while put returns.

this is doing my head in. Cannot work it out

 

[USMC_TOP]

Leave it alone it goes away

 

[alrock]

Take off the belt - does it still occur? Crank engine and let it run for just a moment. Or, with belt on, does it change with a/c on or off?

 

[skippy]

alrock it doesn't do it when the belt is off and the aircon makes no difference?

 

[LagunaH1]

..so it's one of the engine accessories?

 

[skippy]

no it is definitely coming from the crank pulley

 

[alrock]

That would be a bit odd since the crank is what drives the belt but belt noise is caused by belt slippage. Theoretically it shouldn't be slipping on the crank pulley but would instead be slipping on another pulley like the power steering pump (hence that whine you hear with many cars with cold starts and/or failing pumps).

Then again, let's say the power steering pump is holding back the belt that would mean the crank pulley is moving faster than the belt and thus the squealing.

Please take my opinion with a grain of salt - I'm just using a bit of logic here, this isn't based on direct experience.

 

[4speedfunk]

Yes. Just because there is squealing at the crank pulley....doesn't mean that's where the problem is. It could be one of the other accessories that is putting a load on the belt, and it just happens to be slipping at the crank.

I once had an AC compressor lock-up on a 91 Suburban. It stopped the motor dead. Hit the starter...nothing. Not even a "clank". Totally locked up. The compressor was replaced under warranty...problem solved.

 

[Happy Hummer]

May we know the brand of tensioner, pulley & belt?
Chris

 

[Chook]

Not my Hummer but our Ford Focus has had this twice........ The first time it was the water pump............The second time it was the Idlers

 

[skippy]

they are oem pulley and the belt is gates

i checked all the accessories and they spinning extremely free?