Thread: Any A/C guru's on here?

Hi all.
Is there anyone on here who's pretty switched on with car A/C?

Just after some advice.

The problem i have is, when i start the car on a cold morning i get a whine from the a/c compressor for around 20 seconds.
If i start the car with the a/c off its fine.
Also, the aux belt and tensioner are new..so can rule them out.

I have tried a re-gas to the specified 750g... which didnt change anything.
Have also tried running with 700 and 680g of refrigerant in the system, to hopefully take some load off the compressor.
Neither changed the noise.

(whilst at it i dumped 25g of PAG in there to help lubricate the system)

Now im stuck for idea's short of renewing the compressor.

What usually takes the wear?.. is it a bearing or the clutch?.

Any help appreciated.

Originally Posted by csweatherston

Hi all.
Is there anyone on here who's pretty switched on with car A/C?

Just after some advice.

The problem i have is, when i start the car on a cold morning i get a whine from the a/c compressor for around 20 seconds.
If i start the car with the a/c off its fine.
Also, the aux belt and tensioner are new..so can rule them out.

I have tried a re-gas to the specified 750g... which didnt change anything.
Have also tried running with 700 and 680g of refrigerant in the system, to hopefully take some load off the compressor.
Neither changed the noise.

(whilst at it i dumped 25g of PAG in there to help lubricate the system)

Now im stuck for idea's short of renewing the compressor.

What usually takes the wear?.. is it a bearing or the clutch?.

Any help appreciated.

Can't remember his Username - but if you read through this and the General Chat links, you'll see a guy who's signature has feq asked Q's on A/C

You're thinking of Staz.....

Cheers guys, ill drop him a PM.

Hello mate,

to be fair it's more a mechanical problem than an air con one. The PAG is used to lube to seals in the pipes and the compressor internals so I'm not surprised that it didn't solve the problem as it does sound more like it's down to the external parts. If you've changed the tensioner and the belt (and they're fitted correctly) then I'd suggest it's the compressor pulley bearings.

I'm no guru by the way. I did an ECS course in 2007 and haven't used it since so please don't take anything I say as gospel, I'll help if I can though

Ahh, cheers for the reply Staz.
Im pretty sure its the compressor pully bearing/s.... Are these servicable?
My Other option is to dump the gas out, so the ac clutch wont come in....hmm

Well you can disable the clutch by removing the fuse/disconnecting the connector anyway mate if that's all you want to do. I'd have thought you'd need a new compressor if it's the bearings but I don't know. It'd probably be almost as cheap to get a reconditioned compressor anyway, plus you'd get a warranty on it.