North American Turbocoupe Organization

I had my A/C compressor go, and traded for one off of an 87 TC, as well as the lines that go with it. Here is what I learned in the process of the swap:

1. The wheels for the compressors are real easy to change with a gear puller and a lot of PB Blaster. Once the drive plate is pulled with a gear puller, the rest is relatively easy.

2. Not only is the drive wheel different, (v-belt vs serpentine,) but the lower mount is different. The mount on the 83-86 TC is a bracket, and the mount on the 87-88 is a bolt hole. Looking through the yards, most of the other compressors of that type matched the 87-88.

3. The bracket on the 83-86 compressor is hard to remove without destroying the compressor. We ended up cutting up the compressor and grinding the parts off of the bracket that weren't bracket, and then ground the lower bolt hole off of the newer compressor. The guy doing the welding arc welded it with some wire-feed welder. We turned the drive plate between welds to clear the hot air out of the compressor to reduce the chance of damage. If I had needed a compressor for an 87/88, I would have got one from one of the mid-80s Fords, Mercuries or Lincolns with the same bolt pattern. Quotes for labor ran from $40 with no guarantees, $20 if I ground off the bolt hole from the 87/88 compressor, or a 20 pack of Bud Light dropped off at a shop where I used to work.

4. The line from the condensor to the firewall (containing the expansion valve) is different. The 83-86 has a nut instead of a snap-lock on the firewall end.

5. Both of the expansion valves were pretty clogged, and could barely be blown through. I cleaned both before I realized the 87/88 line wasn't going to work.

6. Looking back at how things worked out, one of the last things I did before the system died was add R134 with an oil charge. I'm guessing this was PAG, which I have since read (and probably read long ago and forgot,) is detrimental to systems formerly running R12. Looks like that forecast verified.

Hope this helps someone.

Nice write up Mike! You wouldn't happen to have any pics would you?

A few. I'll put up a web page when I get time.

well, PAG only destroys systems that used to have R12, THAT WEREN'T FLUSHED PROPERLY. ive done a TON of conversions, and not properly and totally purging the system will cause failure, either soon or sooner. when not flushed, or poorly flushed, what happens is the gunk that is already in the system(the stuff you found in the expansion valves)soaks up PAG oil until it clogs completely. sometimes this alone destroys a 20 yr old compressor. however, usually, the big hunk of garbage breaks loose, and basically turns into a clot. it finds its way to the high side of the compressor, and boom, the seals blow out, or it takes out a bearing. if you flush the system, then charge it, then recover it properly(creating a 1 lb vacuum in the system)then recharge, you can almost always avoid this.

good job on the swap though, and id have never thought of using the far more efficient 87-88 compressor.



-J0N

JON,

You were right about not flushing - I originally just used one of those $40 retrofit kits once I had all of the R12 pulled from the system. I've had to refill a few times due to seals blowing, and never flushed. I guess this incident is a good example of why one should flush the system when switching.

Except for the bottom bracket/hole and vbelt/serpentine thing, I thought the 83-86 compressors were the same as the 87/88 compressors. Are there other differences? I had momentarily thought about switching to the system on the early 90's mustang, but wasn't sure about getting a vbelt wheel onto it, or how to adjust tension.

A few pictures have been added here .