Pull the cover off the old one and see if the "O" ring is part of the problem.

 

Just wondering: how did you conclude it had enough gas (R134a) in it?

 

The 50psi ish low pressure reading shows that there's a proper charge...

Take care,

George

 

Back in the fall, when this problem first really occured, I put a cheapie Auto Zone dial gauge on the low side and I had gotten a reading of 125 psi which would be an over charge. I have never put any refidgerant in it.

Of course I said the hell with it and fix it over the winter............well that was one fast winter!

 

Was the car running and the A/C on? That 125psi reading (albeit with the craptastic AutoZone gauge), seems WAY high, however when the system isn't running, the high and low side pressure equalizes.

I'll call you in a few mins,

Take care,

George

 

You mean it should be able to pump harder and result in a lower low-side pressure?

 

Sort of. If the car didn't have enough freon (under 25 psi) on the low pressure side, the compressor would not engage.

When the system is at rest, the low and high side pressures equalize. Normally you see around 40psi on the low side and 200-220psi on the high side when the compressor is engaged. In this case, the compressor is working BUT not at it's proper level - there is probably a failed seal between the low / high side causing some bleedback, so the low side never drops all the way to 40psi, and the high side never reaches where it needs to be for proper cooling. Does it have the proper level of charge, we don't know, but it has enough charge to diagnose the malfunction of the compressor.

If the compressor was ok, you would see the same 40psi on the low side, and probably 175ish pressures on the high side if the charge was low, but not full. The car would have cool, but not necessarily cold air, but it would be consistent.

The jitter on the gauge on the low side is the tell tale sign here. Obviously that is indicative of a leak, or a failed bearing in the compressor causing it to bleed pressure back to the low side.

Take care,

George

 

^^^Thanks for the above George^^^

Saga continues, yesterday George sent me an ebay link to a Jaguar OEM NEW compressor (Jaguar S-Type *NEW* A/C Compressor 2004-2007 | eBay)

Auction ended last night with my winning bid of $110.00 plus $15.00 shipping. Great Deal!!!

The wrong remanufactured will be shippped back with full refund!

Thanks for the heads up on the OEM George!!!!

 

Thanks George - but to play devil's advocate:

1. couldn't the low dropping to 50 (instead of 40) be "just what the jag does"?

2. couldn't the jitter be due to 50-ish being the lowest the jag goes and so it's repeatedly tripping?

I suppose these are the same as asking "how do you know that 40 (rather than 50) is the target low-side operating pressure for the jag's a/c"?

 

Just from practical experience / measuring my own car, 40psi low side, 210psi high, air cold enough to need a coat in the summer and cause condensation around the vents.

The jitter isn't the compressor going on / off... you would see spikes as the pressure started to equalize (more than +_ 4psi).

The PROPER way to charge a 134 system isn't by measuring pressure, but by measuring weight of the gas. This is done via a digital scale on the r134a tank. You can get CLOSE using premeasured cans, but it's not accurate. Fortunately there is a fair amount of variation allowed in terms of actual refrigerant quantity that the system will still operate under.

Take care,

George

 

I measured mine but can't find the readings!

(I do know how to check / hold vacuum / recharge / etc, thanks.)

 

This worked for me and it might help you and I hope it does.

http://www.gusglikas.com/images/Auto...s/ACSystem.pdf
http://www.gusglikas.com/images/Auto...or%20Codes.pdf

 

UPDATE:

Just received the new OEM compressor a few minutes ago. There is 1 difference between the new and old, I will post pics later, otherwise the new one has the 4" casing bolts rather than the 3 1/2".

I will be installing tonight.

 

WOW what a fast weekend! Little update, installed new compressor and with Georges help got it all charged up and yes Joyces Jag is now blowing ice cold again!

As mentioned earlier I have pics and I will do a complete write up. Really was a simple job on a 3.0 litre.

 

Very impressive, Rick. Did you have an A/C shop do the 134a charge, or did you do it yourself? Again, I'm impressed but not surprised. I think you can fix most anything that these vehicles can throw at you....

 

He vacuumed it down and charged it himself with a little help from his friends

Take care,

George

 

Thanks for the additional input, George. I didn't read Rick's last post closely enough. I should have known that you were part of the solution!

My wife has me very busy with home repair projects lately. Not much time to spend here on the forum. And with our S-Type running perfectly throughout 2011 thus far, not many questions to pose, either. I guess that's a good thing....

 

Ok as mentioned earlier, I purchased a "new" OEM AC compressor off ebay for MYs 2003 through 2008, 3.0 litre. It does infact have a Jaguar sticker on it.

There is 1 big difference between the old and new. The new did not come with the black cover plate as seen in the pictures. I have taken a couple of different pics for everyone to see "whats behind door #1", and it isn't a goat .

The small black cylinder on the left is a 2 part micro filter, in the 3rd picture.

 

Rick:

I am curious- did you put the cover plate on the new one? I looked at AllDATA and they indicate you need a


Did you have any use for these items or did you work around it or is this a false positive.

Thanks

'Tom in Dallas
2005 S-Type 3.0 58K

 

Tom are talking about the compressor?