Air conditioning squeaking

[bluegrommet]

It's getting warmer here in Melbourne, and I've had the air conditioning on a few times in my 2003 WG 2.7 CRD recently. I noticed the system was not really blowing cold air - shoot, gotta re-gas it I guess.

Last week though I noticed a faint intermittent squeaking when the system was running whilst driving. The squeaking was much louder when I got out of the car - clearly coming from the engine bay. It only squeaks when the AC is on - nothing when the heater is on.

It's not a screeching like a slipping belt on startup - it will squeak intermittently, sometimes not at all, sometimes a lot.

Any hints on what to do next?

[JeanLuke]

Check the idler pulleys, and the bearing on the viscous heater pulley (the thing that looks like a second water pump at the top of the engine). Take the serpentine belt off, then feel everything for play in the bearings. Nothing here is difficult to fix. Finding which one to fix can be hard. When the compressor is running, it loads everything up and can make a dodgy idler squeak.

The bearing on the viscous heater is (I think) identified in the "Everything CRD" thread, along with the idler pulleys. I would recommend getting metal ones if you are going to replace any.

EDIT: Before you take the serpentine belt off, take lots of pictures to help thread it back on... or get the manual with the diagramme.

[bluegrommet]

Thanks JeanLuke. Well, the good news is that the squeaking noise went away. The bad news is that the air conditioning still doesn't work.

I've hooked up A/C to a manifold gauge set and I read about 100 psi of refrigerant on both the low and high pressure sides. The compressor doesn't engage and there's no movement of refrigerant - manifold needles don't budge. I'm going to take the belt off and see if I can work out if the compressor clutch is bad.

Can I buy the clutch anywhere here - is it generic to other Jeeps maybe?

[bluegrommet]

I've removed the A/C compressor clutch relay and bench tested - all good. I used a short wire in the relay ports to jump the clutch manually - jumper connectors spark, but clutch doesn't move.

Now to try work out how to remove the thing - I've got about a finger or two of room between the bearing and the hydraulic fan shroud when working from under the car. Not looking forward to trying to remove those snap rings.

No visual on the electrical connector - I'll keep poking around.

[5oclock]

When my aircon compressor went bad it had seized up and burnt the rubber "spring" on the clutch up. So the belt still went around but compressor wouldnt turn. Got a new one from Rock Auto at a good price, much cheaper than here. Dont know what Rock Auto price would be now since our dollar has gone down a bit, but they did have a few to choose from back then. I dont think that just the clutch is avaliable on its own. The compressor is a bit of a bugger to get out because of the lack of room and you have to go by feel, think there is 3 torxs bolts holding it in. Dont think there is enough room to get the clutch off if you leave the compressor in place. Also I used Minus 30 gas instead of 134a, because in Vic you can use HC gas like Minus 30 without any licence etc since it is not a greenhouse or ozone depleating. Minus 30 is cheap to buy. Aircon system charged with Minus 30 is colder and the compressor has lower pressures to work against. If you get a new compressor get a new TX valve as well , because they go bad too and the system will not work well with TX valve that is not in perfect condition.TX valve was about 20 bucks from Rock Auto, and they had new valves and orings as well. Also Minus 30 will work OK with the original PAG oil thats in the system from the 134a . Check out HyChill web site for info and hints on charging your AC system. Good luck , hope you get it working again and let us know whats happening.

[bluegrommet]

Cheers 5oclock - I actually already went and bought a can of Hychill Minus 30 when I thought the R134a had all just leaked out. Hooked up a manifold set and whoops, system still fully charged. I'll hold onto it incase I need to replace the compressor.

Is it possible to try turn the compressor by hand to see if it's seized?

Another thing - I was looking at Rockauto but isn't the compressor on the US petrol 4.0L / 4.6L different to the 2.7L CRD? They look like a Denso 10PA17E whilst I think the CRD has the Denso 10S17C. Will the US model fit?

https://www.rockauto.com/en/catalog/jeep,2003,grand+cherokee,4.0l+l6,1416125,heat+&+air+conditioning,a/c+compressor,6628

[5oclock]

You should be able to turn the clutch plate by hand but it will be hard to turn.
So now I am trying to remember exactly what I did. Bit more complicated in my case since I have a WH 3.0 crd as well as WG 2.7 crd (its not possible to have too many Jeeps!) and I had the Denso compressors crap out on both,the WH came pre-crapped out when I got it.
So the WH compressor has a 7 groove pulley and the WG is a 6 groove pulley. I am pretty sure the 6 groove belt fits OK on the 7 groove pulley.
So I just I ordered a WH 3.0 v6 diesel 2007 10S17C compressor from Rock Auto and it was the same as the 10S17C on the WG except it had a 7 groove pulley.

[bluegrommet]

Wow, good catch on the WH compressor - the cheapest is a UAC $394 inc shipping/tax from Rockauto.

I just went and turned the clutch by hand - it didn't offer much resistance. Given that it turns and that the system is still charged I'd say the compressor isn't seized?

I'll see if I can get the clutch off without removing the compressor - don't like my chances but I'll give it a go. Then I'll see if I can get a clutch for cheaper than a whole new compressor. Would be good to avoid evacuating the refrigerant but we'll see how I go. Cheers for the help so far!

[5oclock]

So there is 1 or 2 shims between the clutch shaft and the compressor that will be easily lost if you are not extra careful removing the clutch, they also can be sneaky and stick on the clutch side or the compressor side and drop off in the grass when you arnt looking. The shim is to get just the right clearance for the clutch and the pulley.
My hunch is the rubber spring is burnt up and part of the clutch plate was rubbing on the pulley face making the "squeaking" noise. May be moved a bit and stopped making noise now. This is pretty much what happened on my WH. So I put a "new" clutch on it from my junk box of Jeep spares and all was good for a few weeks till the compressor seized again and burnt that clutch as well. So then I put the new compressor in. You will soon know when you pull the clutch plate off if its no good.