Hi to all,

Need some advice on the a/c compressor swap on my 1988 XJS. The new compresor replacing the Harrison A6 is an aluminum FourSeasons (FS) 58096.
On the attached picture you can see the following items A, A1 and B, B1.





A, I think this is the low pressure safety switch on the A6, on the FS on A1 it seems to be provision for this switch, but no switch, should I just transfer the switch with a new o-ring?

B looks like a high pressure relief valve, but is much larger in dimensions than B1, am I correct and is B1 equivalent to B?

I still have more question on oil and gas capacity but don't want to make this thread to confusing.

Alfredo

 

B1 looks like a plug to me, rather than a relief valve. The earlier compressors had a superheat switch, and the later ones a pressure switch. They are not interchangeable, but it looks like you have the pressure switch. It should transfer across.

Make sure the snap ring is in good contact with the switch, as that's the only electrical connection to the body of the compressor. If the body of the switch isn't making contact with the compressor then the circuit won't close and the clutch won't engage.

 

Thanks so much for your reply, will leave B1 alone and just transfer A switch.

 

Curious of your decision to swap to an aluminum compressor...original Harrison finally gave up or converting to newer freon since R12 N/A? If you're converting to newer freon, are your replacing hoses/fittings, as well as a new style condensor?

Dave in AZ (where A/C is not just a luxury)

 

The Harrison just gave up, charged the system a couple of times and the charge just lasted a few days each time, the dye shows it's leaking all over the place... It's a pity there are no proper seal kits for this compressors any more. Both charges were done wit R134, and it worked very well while it lastes, so I think besides the compressor,leaking, the rest of the system is in good condition, but I will be changing the dryer any ways, it's very simple and very cheap... The expansion valve is also very cheap to buy, but kind of tight to change and many chances to brake something, and since the system seems to work well (except for the leaking compressor), I will leave it alone...
I just need to make a decision on the amount and type of oil to use, on the following images, the Harrison is supposed to take 10 oz. ocording to the sticker on the compressor:

On the new compressor, the sticker covering the oil filler plug says it comes prefilled with 3 oz. of oil and to adjust according to a chart via a QR link with the following lines referring the XJ-S:


And finally, the new compressor came with the following "card" that states that PAG 46 oil is required, and that for A6 models you have to reduce the amount of oil by 3 oz... :

To be honest I am really confused, should I use 10 oz as per the Harrison sticker and reduce that by 3 oz acording to the yellow card for a total of 7 oz? Should I use PAG 46 oil? Or should I use 6.5 oz of Mineral Oil as per the pdf...
I hope some one can give me some advice...

Alfredo

 

Can't help with the new compressor, but the old A6 has a sump, so that's why it takes so much oil. New compressors generally don't have a sump they just push the oil around.

R12 was fully miscible ( disolvable) in mineral oil, R134 isn't. That's why the new types of oil were developed. With R12, you had a mix of oil and freon circulating, so everything was well lubricated all the time. One of the new types is compatible with mineral oil, and one isn't I can't remember which is which. I would probably want to do a flush and get the old oil out and start with clean oil (PAG 46).

 

Thanks so much for your reply, it makes sence, yes, the now compressor does not has a sump, that might be the reason the yellow "card" indicates reducing the amount of oil by 3 oz.
On the oil type you are correct, it's ESTER OIL the one that can be used with either R12 or R134a..
I will keep reading about this retrofit in otjer cars that use the Harrison compressor.
Again, thanks for your help.