I will be soon pulling the heater/evaporator housing to replace the heater core. While I have it out and apart I thought it would be a good time to replace the evaporator core as well. I know there is a leak somewhere in the system so I would rather do it all at once. Are there any other parts I should look at replacing while it is torn down, and are the evaporator cores available for these cars? If not is there a compatible part?
When I couldn't find one, Classic Auto Air "refurbished" mine for about what I'd expect to pay for a new one. Think "refurbish" means clean, inspect, test and repair if necessary. A local AC shop declined when I asked them about testing it. They didn't want to bother finding fittings to fit the old connectors.
I had a local shop test mine ($20.00 also) and it proved to be in operating condx. While u have it out clean all the rusty metal doors, paint them w/ some kind of rust inhibiting paint and it's a gud idea to test the vac motors in the system. Also, all the foam seals in the box will need replacing frm dry rot. I believe I used a Mustang seal kit in mine which required some minor alterations to fit the Mav box. Im not sure which kit I used but I can ck my purchase records and hopefully find it.
The only thing pressure testing will do, is tell you if it's holding pressure, at that time, anything could happen, 2 days after, 2 months, 2 years....I wouldn't pay more than 20 bucks to have it done...
Thanks guys. I was wondering if any of the Mustang stuff would work. I will see about picking up a seal kit for one before getting into it.
If you still happen to have it out then I may be of some assistance. I believe these cars had a TXV that comes out right above the heater core. (Looks like a square black box with a saucer-like top plate. It separates the low side from the high side of the AC system. Sometimes these can get either stuck open, or stuck closed if the spring inside is broken or if the diaphragm is cracked. There are several signs signifying one of these occurred, but you would need AC gauges to test it and these can get fairly expensive if you don't have them already. Another issue concerning these old systems is the R12 they were designed to run with. It's become a little more expensive to even purchase R12 these days and I've heard that you need a Universal license to even get your hands on it in some cases. The problem with this is, the hose fittings and even sometimes the hoses themselves are not compatible with HFC-134a if that's what you're thinking of putting in there. (The molecules are significantly smaller and the seals will not hold it in) Most places you can go to get the AC system checked will probably vacuum test the system and then pressurize it with nitrogen (since it can be vented) and test for leaks. I would suggest asking them about restoring the AC system as they may have some more information for you. Good luck with getting it all back to working order! It would definitely be cool to have an AC system that blows cool in one of these old cars. Edit: Here is a picture of the expansion valve I was talking about earlier.
