I need your advice.

My 1993 XJS 6.0 V12 coupe has a faulty air conditioning compressor.

It was one of the last models fitted with R12 refrigerant.

The compressor leaks at the end nearest the drive belt.

It seems like my options are replacement compressor or attempt to repair the compressor (assuming appropriate seal kit is available).

I have read quite a bit about air con on this and other Jaguar forums.

I know R12 not available so my options seem either R134a or an R12 replacement.

I am leaning towards either R406a (mix of R22/142b/600a) or Isceon MO49 (R413a - a mix of R218/134a/600a)

My existing compressor is Sanden SD709 (unsure of type number)

I am aware Sanden seem to have good reputation and current model is SD7H15

as to Jaguar part numbers there seems to be a lot of confusion regarding MHE7300AA or
MHE7300AB

Some say the model for 4.0l won't fit 6.0l but is incorrectly listed as compatible on certain supplier sites.

I need your advice regarding my concerns above.

 

Can you actually buy the stuff you are talking about using? You can research what is best all day but in many places you have to have a license to buy it.

 

Should have said I live in UK.

I know one of the above refrigerant wasn't available in US.

I haven't checked extensively but at least two air con service places were offering these R134a alternative.

Incidentally I believe R134a is due to be phased out in 2017.

 

Paul
You might be over-thinking this a bit. It would be best and undoubtedly quickest and probably cheapest to get a decent car aircon guy round. Pretty much all Sanden cylindrical pulley-driven compressors will do as far as physically getting it in is concerned. My car has one as previously used OEM on the 4 litre cars and XJ40s. The critical thing is aligning the pulley with the crank pulley. The compressor to engine fixing bracket is just a lump of steel that can easily be cut and welded to suit if needed. Modern click-on click-off fixings to use modern aircon loading and testing equipment will go straight on to the Sanden. Conversions from R12 to more modern gasses were done pretty roughly, so there is no guarantee your old converted system was 100% to begin with.
The aircon guy will know what gas to use, will know which flexibles to replace the old ones with, if that is needed from the leaching out of the gas through the hose material point of view. With the modern kit they have, it will take all of 30 minutes to leaktest, fit the compressor and charge the system.
New compressors are not cheap, but the rest should come in under the 100 quid mark. Evacuating the system yourself is damn-near impossible, charging it properly and safely ditto. And if you have a leak, the guy will find it and where it is, so it can be fixed before going any further.
Just my ideas, but it worked for me, as I think the car is undriveable in summer without aircon!
Greg

 

Thanks for your reply Greg, I always tend to overthink things!

Should have been clearer, I took car to air conditioning business recommended by a Jaguar specialist (David Marks garages, Nottingham)
They connected to their system, my air con was empty, previously had R12, never been converted.
The test showed wouldn't hold vacuum, leak was on compressor.
I asked them to supply and fit whatever needed to get working.
Wasn't bothered if they repaired or replaced my compressor.
Numerous phone calls to chase progress, got nowhere. Assumed I was on my own. Tried to buy compressor Sanden, Hella suppliers stated no stock and couldn't get any.

I know a compressor is just a pump and only needs sufficient capacity.

However I can't weld and as it's my only transport I didn't want car off road .
Just want to bolt on compressor and take it to air conditioning service to charge with refrigerant , hence preference for getting a compressor that will bolt on to existing bracket if possible.

I am aware compressor not cheap, prepared for approx Ł200 to Ł300 for compressor.
Not wanting to go the Jaguar Ł800 route for identical compressor.

 

I quite understand. The seal at the front is the weakest point on all compressors, and the main reason that, if you lay up the car for the winter, you should give the aircon a 15 minute run every two weeks. Something to do with it drying out if it does not get a lube feed from the oil in the gas, I understand.

Somewhere on here there is a thread with the Sanden compressor part number that I used on my car. essentially, any aircon guy can fix it, does not have to be Dave Marks' recommendation; there is nothing difficult or unusual about the system; so no specialist XJS knowledge needed at all. I suggest you go to a decent local garage and ask them who they use. Then it should just be a compressor and a dryer and a charge, as you know the rest of the system is fine.


Here is the link to the thread. I did not have to do anything to the bracket, but if you do, anyone can cut and fix it for you at the local under the arches place!
https://www.jaguarforums.com/forum/x...pgrade-126362/


Greg

 

https://www.jaguarforums.com/forum/xjs-x27-32/ac-compressor-95-6l-v12-xjs-question-117522/#post991167