Air Con Compressor

[zwhitea]

Can anyone offer any guidance on a problem i have with the air-con compressor.. It appears that the clutch no longer engages when the A/C is turned on, and you can hear a continuous squeek (like a slipping belt but not)..

Is this something which could be easily repaired, or would it be better to get an exchange unit..
Has anyone suffered a similar problem..?

adam.

 

[Dave Wilkinson]

Adam,

It's really a matter of trying to isolate where the problem is. The compressor clutch is electrically operated and makes a very distinct "snap" as it engages. It can be prevented from engaging if the system is low on refridgerant but from your description it sounds as if the clutch is engaging but the compressor is failing to turn. If this is the case it may be that either the clutch itself has failed or, perhaps more probably, the compressor has seized.

You can turn on the a/c with the engine stopped and you should be able to hear the clutch engage. If the compressor is seized I would imagine the clutch would break before the belt would stop.

If you CAN hear the clutch engage I would imagine the next step would be to remove the compressor and get it checked out in isolation.

Regards

Dave

 

[johnk]

when engine is off try turn the centre of the a/c compressor by hand or by the 13mm nut in the middle of it if this doesnt move it has seized. but may be just a gas problem..

 

[zwhitea]

Thanks for your responses...

Haven't had chance to hear if the clutch engages, as I haven't had 2 pair of hands yet.
As for being seized, then I know it isn't as you can turn it easily by hand..

I'll try to hear if the clutch operates tomorrow, as I guess it still could just be electical..
Hope its not the refridgerant as it was only re-gassed and pressure tested a couple of years ago, so if its low I've got a leak.[]
Does the 993 have a A/C spy glass for refridgerant levels, or any warning lights.?

Oh well, when it rains it pours.. my 3.2 is currently having its A/C system overhauled, who know what that's going to cost..

Adam.

 

[zwhitea]

I thought it was the belt initially, but this is tight.. and isn't slipping.. The assembly I can move by hand is just the magnetic clutch and not the pulley.
I have since had a meter on the system, and the feed wire to the clutch is only getting under a volt... ?

I have had a look through the wiring diagrams I have (which are not the best) and can only assume it is either the relay or a pressure issue, unfortunately I can't trace or understand what the "3-level Pressure Switch" does and haven't got a spare relay to try at present.

I have also been offered a second hand compressor for £175 which came from a very low milage 993 before it was turned into a track car, which sounds like a good deal to me, if that turns out to be one of the issue.?

Adam

 

[cytefx]

if you do not need that second hand compressor, I am willing to take it off your hands

 

[zwhitea]

Well.. Found out what's wrong with the A/C.. it isn't a leak or the pump..
But a blockage messing with the expansion value, which in turn is messing up all the pressure resulting in the 3-way switch cutting off the A/C..
The A/C Man expects it is all down to the dryer degrading and breaking up..[]

End result is that no A/C on the 993 this summer as it is one hell of a job to sort out, its a good job its a Cab.[8|]
And a big bill over the winter as the fuel tank, and most of the bulkhead fan assembly needs to come out, just to gain access to the value.. Thing were far easier on my 3.2 Coupe.. Which now has great A/C again..[]

Let this be a warning to you all... Ensure you get a new dryer fitted as part of your recharge, especially if you don't know how old it is, they are relatively cheap and just inside the front wing..

Adam

 

[cytefx]

So, if its not the compressor, want to sell that spare you have, mine has got the clutch wires broken when the belt snapped (ironically just before it was due to be serviced)

I have been looking, already brought one but it was a little knackered, I have been able to pull of the clutch but i would prefer a good compressor in tact.

thanks