I just put on the R-134 fittings and checked to see if there was any pressure in the system and there was none. So I just went for it and loaded up all 3 12 oz bottles and the compressor clutch only engages for second every 15 sec or so and while looking at the pressure gauge on the R-134 filler the compressor kicks on when the gauge reads 45 psi and shuts off quickly and the gauge drops to 25 psi. The pressure slowoly builds and the senario repeats. I searched previous posts and read about the low pressure sensor in the compressor that will disengage the clutch when the pressure drops. I figure that there is a leak in the HP side maybe but at this point do not know. There is a compressor from the same year truck (1985) at the junkyard if needed. The crappy chilton manual mentions nothing about AC repair so could someone tell me if it is worth it to fix it? I live in southern Cal so it would be nice but its not as important if I lived in Tucson.

 

Before you put the 134 in the system, did you pull a vacuum?

Did you put a can of oil in it too? You should.

I wouldnt worry about the compressor. From what you are saying, it is probably working.

If you have a freon leak, you will see some oily residue at the connection or part that is leaking. That oil is refrigerent oil.

I converted my '83 to 134 year before last. First thing I did was pull a vacuum and let it sit for an hour or so with the vacuum. I had no leaks, as the vacuum gauge never moved during the hour.

The only bad thing that happened was that after I put the single can of oil in the system, my helper came back and added another full can of oil. Therefore, it could get colder than it does, but it does just fine for heat in the Western NC mountains

You might need to bite the bullet and start over with a vacuum.

Good luck!!

 

It was and R-134 kit so it had an ester oil mixed in. YOu had to shake it while filling. Whats the preffered method to find leaks?

 

A/C systems are still extraneous to the basic engine function. Engines have good reliability, vast source of replacement parts...readily replaceable by a decent shadetree mechanic. A/C systems are less reliable and more difficult to repair by DIYers. I enjoyed my A/C for the years it lasted (with too many repairs), so when it crashed the last time I just said forget it, I'll just drive it in the cooler mornings (Texas). It wasn't worth risking being a money pit.

 

I may of missed but if you retrofit an R12 unit to R134A. You must flush out the mineral oil, change the filter/dryer out,O-ring seals, fill with an ester oil about 5-7 oz. Then pull a vacuum for 30 minutes, then let it set for 30 minutes to see if it stays, if not you have a leak. Remember R134A is a synthetic fluid so it will leak where R12 didn't. Then charge with R134A. R134A should be only 80% of what R12 calls for. You can add a dye that will show leaks. Most leaks are COMPRESSOR FRONT SEALS. AutoZone sells rebuilt's fairly cheap. I just converted my wife's Dodge and had to replace the compressor. It works great. We are in 118 degree temps and it will only get hotter before it gets cooler. Nights are 90s. So A/C is kind of a must here. Unless your real tough. Me I like comfort. I have very little trouble with A/C. Lack of use is the worse thing for them. My 86 F250 4x4 had to have the compressor replaced in 1999, after 13 years. Every three or four years I have to add a can of R-12. I replaced the low pressure switch this year. Other than that I have had no trouble. The trouble comes when people try to do A/C work that don't have good A/C experience. A/C units are very simple if you know how they work and how to service them. I carry an EPA Type I &II certification along with an ASE Cert.

 

This is very true kermmydog. AC systems aren't tolerant of mistakes or shortcuts "just to get it working". It's a case of "Do it right or do without".

78Sharpshooter:
You are blind without knowing the high side pressure. If you want to fix the system, you need access to a manifold gauge set, a vacuum pump, spring lock fitting tools and a proper can tap. With 3 cans of refrigerant in the system, it shouldn't cycle. This"could" be a blockage in the system, but your high side pressure would be skyrocketing. You really need both pressures to have a clue what's going on. You can rent most of the tools from many parts stores.
As a DIY project, you could replace every component under the hood for $300-400. The actual repair shouldn't cost that much unless the compressor has grenaded (worst case).

You are going to need (at least):
-accumulator
-orifice tube
-O-ring kit to reseal all of the fittings
-solvent for flushing (lacquer thinner works well)
-Lots of compressed air and a blow gun
-refrigerant
- 16 ounces of ester oil (8 for the system, 8 to flush the compressor)
- Quality STEEL retrofit fittings. The aluminum fittings from that Death Kit are very poor quality and usually leak.

At this age, the compressor seals probably leak. Look for oily dirt on the clutch hub and oil stains on the bottom of the compressor body. A used one is a real crapshoot (bad idea). So are the cheap remans sold at chain stores like AutoZone. www.ackits.com has a NEW, good quality compressor (FS-6) for $199.
Right now, you have an unknown amount of refrigerant in the system, along with an unknown amount of 2 oils mixed running around in there. You need to have the system recovered and then inspect the orifice tube. This will usually tell you the extent of the repair.

As for being worth it, some folks don't believe $50 to fix an AC system is worth it on any car, some will spend $1000 on a beater for working AC. It's all about what it's worth to you.

To get an idea of what's involved, check out the forum at www.autoacforum.com It's sponsored by ackits.com.