So I am getting ready to work on my air conditioning system, to put it right and hopefully not look back! I have a few questions.

First, here's the history: 1987, a/c probably hadn't been used much if at all in ten years (car mostly parked, used in a cooler, rainy climate). Heat has always worked great.

About six weeks ago, I took it in to a local Jag specialist to get the a/c brought up to good working order and have the system converted to R-134a. They said they've done a lot of these and this would likely be pretty straightforward.

Over the course of a number of visits and an increasingly Large sum of money, they kept finding new reasons each time the system was not blowing cold air. I won't go into specifics, but they have achieved the following thus far: a new receiver/drier, a new thermal fuse, a cleaned expansion valve, superheat switch replaced with a low-pressure switch (said they re-wired accordingly, but wiring looks exactly like the diagram Doug recently provided for the superheat switch).

Finally, we specifically focused on finding leaks, using a lot of dye followed by a lot of driving. Although an earlier dye test had only revealed a leak at the superheat switch, this time they found the condenser was leaking quite a bit at fins as well as connections.

The system has been blowing cold for about two weeks now on the latest charge, which is a record, but I don't expect the gas to last with a leaky condenser, and who knows what else, so I'm going to install new hoses, o-rings, condenser and expansion valve, and re-charge the system with R-134a. Picked up a manifold gauge eat and will borrow a vacuum pump.

I've been studying up and think I understand the process and procedures pretty well. But I do have a few questions:

1. I have a very new (month-old) receiver/drier. I would like not to pay for a new one. If I close the ends after opening the system, can I dry it sufficiently when I pull a vacuum not to have to replace?

2. What should I do about adding PAG oil? I assume best practice would be to empty the compressor (the condenser, the other place significant amountsof oil reside from what I've read, is being replaced) and simply add the correct amount of oil. Can I do this without de-mounting the compressor? How much oil do I need for an R-134a retrofit? BTW the shop used PAG 46 so that is what I will use.

3. Where can I find a thermal sleeve to fit the high-side line? New hose did not include it.

4. Any other techniques for making this as simple as possible? (I would rather not debate merits of R-134a versus other refrigerants, please. When it is charged, the R-134a system is quite cold enough for me!)

Thank you!

Andrew.

PS- the original A-6 compressor seems to be chugging along quite well, as is the Delanair system (knock, knock!)

 

1. The recommended practice is to replace the dryer when exposed to air, but i suppose you could reuse it if you do this in a non humid environment.

2. I would drain whatever oil is residing in the condensor, and add this plus about 10%. You can inject the pag by pouring it down the 3rd (yellow) hose on your manifold gauge or by getting the r134a cans that are premixed with pag oil.

4. You can get an electronic sniffer from Amazon for under $50, it will allow you to detect leaks in areas where the dye is not easily visible such as evaporator, non accessible portions of the condensor, etc. Also, dont forget to replace aged Schrader valve cores

 

Lot of options like this, especially if you search the high-performance oriented sites

https://www.designengineering.com/ca...nized-sleeving


Cheers
DD

 

Sorta bodge:


For two or three years, my Jeep needed a can of R134a recharge each season to get back to really cold.


A couple of years ago, I recharged it, but with cans containing a "stop leak". Voila.
So far so good, this year. Nice cold air.


The Jaguar is another story as to AC. At present I am in "information overload" mode.


Carl