You got that right that’s for sure
As far as the refrigeration portion of the system goes, well, it’s plain as mud. Nothing Jaguar-specific. Any known A/C shop with a good reputation (and normal mental/emotional state) can do the repairs
Cheers
DD
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Interesting thread and a sad example of the times we live in. The GM A6 compressor is readily available at most of the name brand auto parts stores. The last one I bought last fall was going in my Corvette. $125.00 with a lifetime warranty. It is not filled with oil so will work with R12 or R134 depending on which oil you install. The clutch can be changed but requires a special pulling and installing tool. When reinstalling the clutch, you crank it on until the proper clearance is obtained. If you go to far, you simply install the removal tool and pull it back off a bit. On the XJS, the compressor is so accessible, you can change the clutch on the car without even having to remove the hoses. The kind of switch on the rear of the compressor is to disable the compressor when it runs out of Freon. The V12 E-Types did not use a switch. The system can be changed or you can just pay attention and disconnect the compressor if it stops cooling. The later Compressors have metric bolts and go by a different number at the stores. Some of the rebuilt units come with a bolt set so it will fit either style. If they say they are out of one, ask about the other style so simply search for a A6 GM compressor. Tell them it is for a Jaguar and the price goes up.
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At the end of April , on advice from several club members, as well as several shops who spoke highly of them, I purchased a 4 Seasons 58096 compressor with receiver/dryer from Rock Auto. A fellow club member suggested I talk to the owner of a shop he’s worked with and had good experience. I explained to the shop owner what I wanted to do: evacuate & save what I believed was a sizable quantity of R12 still inside my compressor with the failed clutch and install my new compressor with the saved R12. As a reminder, my car is a 1987 series 3 XJ6. Well, I’m glad my friend recommended this shop. When I arrived there, the owner unpacked my new compressor and held it up over the engine to see if it appeared to be the right size and shape to fit my car. He then expressed his concern to me that while the back of the new compressor had four holes for bolts, the old one looked like it had five bolts and the new one seemed to be missing a panel on the back into which a pressure sensor is supposed to be attached to monitor the high pressure side of the system. I told him the failed compressor currently in the car was installed twelve years ago by the charlatan who I would no longer do business with, and he had probably used some marginal aftermarket item. So, the shop owner says to me, “OK, we’ll see what we can do, but if this new compressor doesn’t fit, you’ll have to leave the car here and find another way to get home, the car cannot be driven without a compressor installed with loose hanging hoses. Now I was in a real quandry, because the shop’s R12 recovery machine broke last month and parts are no longer available for it. I waited five weeks hoping the parts would be located, but they have remained unobtainable. In addition to that, I noticed to my horror, that since I’d purchased my new compressor in April, the invoice says ‘no returns , refunds, or exchanges after May 31st.’ I told him to remove the old compressor, and see what he could do. When he proceeded to do so, he showed me there was little if any R12 left in the system. He showed me when the clutch failed, along with the main shaft, which could now be wiggled side to side with impunity, there was nothing left to ‘save’. I decided then and there I’ve had it with R12, and instructed him to convert the system to R134… With all the components out, I knew now is the right time to replace all the O rings in the system. So I went to sit down in the office waiting room, trying to get some work done on my smart phone, wondering what I’d do if the compressor wouldn’t fit. 90 minutes later, he walked into the waiting room. “What’s the verdict?” I asked. Rather than answer me right away, he motioned for me to follow him in to the shop to show me the current state of things under the hood of my car. “The good news”, he began,” is the compressor is the correct one for your car, and we cannibalized the pressure sensor from the old compressor and were able to attach it to your new one." “The bad news?” I asked. He turned the pulley on the front of the compressor one sixth of a turn before its progress was halted by one of six bolts holding the clutch and pulley being blocked by the metal bracket which exists to hold the air pump above it. “What can be done?”, I asked. “We’ll have to measure and fabricate a new bracket.” he said. I asked him to do whatever he thought necessary to remedy the problem. One hour later, he called me in to the shop again to look at the new fabricated bracket with the compressor already installed, as he spun the pulley freely. 90 minutes later, he came in to the office to tell me the installation was now complete. He added what I thought was a very reasonable amount to the price we had agreed on for the additional fabrication of the bracket. It was a long, stressed filled day, but in the end I felt lucky I’d found a group of qualified professionals who did a superb job.
Now for the bad news: Though I do now have a working air conditioner, it’s obvious to me R134 does not blow air as cold as R12. I called my friend to ask what he thought. He has a series one XJ6 which he converted to R134 some time ago. "Oh, no, 134 will not blow as cold on these cars as R12. “Why not?” I asked. 134 seems to work fine on newer cars. He then explained that newer cars have bigger condensers than what Jaguar had installed on their older cars.
My question to others on this site is, what, if anything, could be done to make the XJ6 with 134 run a bit colder? It’s not that I couldn’t live with the way it is now, but, if possible I wouldn’t mind having it run as cold as it used to. I think my friend’s condenser theory might make sense, as I’ve noticed it does run colder on the open road at sustained speeds over 50 MPH… and oh, one more bonus… the engine runs quieter, and there seems to be less of a power drain on it when I run the a/c.
Thanks for reading this long post. If anyone has any thoughts and ideas or comments, I’d certainly be interested in hearing them. Thanks…
Mel R.
Mel,
I am glad that you were able to get someone to work on you A/C system so that you now have some cooling air again.
It is a well established fact that older A/C systems modified to run on R134A will not blow as cold as the original unmodified systems running with R12. Search the Jag-Lovers archives and the Internet and you will see this mentioned many times. This is the big disadvantage of converting from R12 to R134A and there is nothing that you can do about it in your Series III XJ6. This is exactly the reason that I have kept the A/C systems in my Jaguars working with R12 and spent such a significant amount of time, effort and money to do so.
Paul
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As Paul says, Mel - no way. Or rather; you may find another service minded magician like the one that fixed your original problem - and install a bigger evaporator.
The obvious solution is to reconvert back to R12 - which here in New Zealand is illegal. So I have to live with drawback of a ‘warmer’ AC…
Frank
xj6 85 Sov Europe (UK/NZ)
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I think the secret to have 134 cool to a more tolerable level as is, requires driving at sustained highway speeds and not sitting in slow moving city traffic .Yesterday I drove 11 miles on the highway to a destination with little traffic, going 60 MPH all the way there. Now it’s true temperature outside was not terribly warm in the 70’s (F) with high humidity, which, coupled with bright sunshine, still made outside temps uncomfortable. As I entered the highway and turned on the a/c, I was pleased to feel cold air blasting on to my face like in the ‘good old days’ of R12. After several minutes of driving, with the fan speed set to ‘auto’, the fan even went down to a lower setting. After leaving that destination where I had been parked outside for ten minutes, the a/c fan went back to the high setting and was not as cold as I would have liked, but after a few minutes on the highway, it felt cold enough once again. If the a/c ever breaks on my other XJ6, which still has R12, I’ll do whatever it takes to have it fixed using only R12. Thanks Frank
Mel R.
Frank,
Do mean “evaporator” or “condensor”?
I have heard that the newer more modern cars with R134A A/C systems have larger condensors or maybe with a lot more surface area and fins to dissipate heat better because R134A isn’t as efficient at transferring heat as R12. I can see that a larger evaporator could bring more cooling air into the cabin, but only up to a point. But a larger and more efficient condensor might be a better option especially since the condensor is so easy to access and the evaporator in buried deep inside the dash and requires a great deal of work to access.
I am not proposing such a modification, and I suspect that there would be a lot more to it, but I am trying to understand better how the A/C systems work.
Paul
Paul, the key is to have all of the components “balanced.” On a given system, increasing the capacity of the evaporator, compressor, or condenser will benefit cooling. Or, ideally, all three. In practice, what works best depends on the original design of the car.
Many cars suffer from too-small evaporators due to space considerations. The Series 1 XJs (the first Jaguars to switch away from evaporators located in the boot) are infamous for this. Cooling is barely adequate if that, and nothing can be done excepting substitution of an under dash aftermarket unit, or substitution/addition of a rear evaporator (the Mark X unit actually fits perfectly, and was in fact used on very early Series 1s). The later S2/S3 evaporators are much better, but still not as big as the boot mounted units, nor as big as the contemporaneous American car evaporators.
Condensers of the time were all “serpentine” design and roughly equal. Some cars had extra layers of tubes (e.g., Corvair), roughly equivalent to adding “rows” on radiators. But with R134a came “parallel flow” condensers that are intrinsically about 30% more efficient than serpentine. So swapping a (ideally larger) parallel flow condenser is considered an almost mandatory move if switching to 134a.
Our compressors (2 cylinder York/Tecumseh; six cylinder GM A6) are quite adequate, and in fact are sometimes downsized to reduce parasitic drain. The A6 is supposedly good for about 5 tonnes, which is suitable for a good sized house. IMHO.
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When the fans drop to low speed, Mel, it indicates that the system has brought cabin to the set temp - and the system goes into ‘blend’ mode; tempering air with the heater…
Frank
xj6 85 Sov Europe (UK/NZ)
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I mean the evaporator, Paul - that’s the one providing the cold air by evaporation due to falling pressure. The condenser liquefy the refrigerant for repressurising by the compressor…
A bigger condenser may be required if the evaporator is enlarged - but condenser increase will in itself not increase the cabin cooling effect.
I was a bit tongue in cheek; there is no way to replace the existing evaporator with a larger one. However, one may put a larger evaporator somewhere else…
Frank
xj6 85 Sov Europe (UK/NZ)
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Hi MRCHB.
I am about to embark upon this work only as a DIYer. I have been researching compressors and like the 4 Seasons 58096 compressor. I am worried about the fitment in the car, primarily because of your post. Pictures of the 58096 on some sites show those bolts on the clutch assembly and they look to me like they will not clear the lower compressor mounting bolt/bracket while spinning. Other pictures of that AC Compressor (at Summit Racing for example) don’t show any bolts there.
Is there any chance you could snap some pictures and post or email to me showing the installation on your car. I’d really like to see how this compressor is bolted up on an XJ6 before buying one. I’d like to know what I am getting into before I buy the parts. And believe it or not, you are cutting edge on the interweb for this work. Everyone else seems to talking about an old compressor model. I called 4 Seasons today to make sure the 58096 had those bolts and the person said yes. But it is hard to describe location of bolts in a picture or a mechanical part.
I’m trying to avoid buying a reman’d original in all its 38 pound glory for the only reason is it is the only thing that will fit without bracket modifications. Also, there are bracket adaptors available at Summit and I’d be interested in seeing if any of them might fit to solve the bolt issue.
Cleaning the condensor can make a big difference in hot weather. You can clean with home hvac chemical cleaner. purchased at home depot. this will make a difference there’s all kinds of stuff in the fins. Also could make your car run cooler seeing has its in front of radiator. Just my suggestion.
I stopped in at Home Depot and purchased the spray cleaner, following instructions and rinsing off with water from a garden hose. While I was at it, I sprayed the outdoor air conditioning unit at my home as well. I think the cooling capability was improved somewhat on the home unit, but don’t know if much, if any improvement was made on the car. To be fair, we took the car out for a drive on Sunday to an area where daytime temperature hovered around 90 degrees F. On highway speeds cooling was acceptable, though not as ‘biting’ cold as it was when the car was filled with R12. The limitations of the R134 system became more apparent when sitting more than a minute in slow stop & go traffic. But, even when the car was filled with R12, it always ran colder on highway speeds and less cold when sitting in traffic. At any rate, it is what it is. Knowing what I know now I might have preferred paying the extra $$$ to have filled the system with R12. On the other hand, if the cooling level remains acceptable, if not ideal, for a few years, before it needs a refill, at least I will have the option of purchasing a can of R134 at a reasonable cost and topping it up myself.