[V6-12v] Removing AC compressor

[apowell at colocougs.org]

Tom Christiansen <tomchr at ee.washington.edu> asked:

My A/C compressor has seized. I do intend to replace it... I have a rough
idea of which parts need to be changed (drier/receiver, some little screen
that I forget the name of, the compressor, some o-rings).

The question is: How much work is involved with changing the compressor?

I've been looking at it from the top... Looks like it's more or less
impossible to get at the parts from the top. A bottom up job... Looks like
the oil filter may be in the way. Will this compressor job require that the
oil filter be removed or that the oil cooler be removed? What are the
common snags of the procedure?

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Never let it be said that a Cougar won't take time to help a Husky.

Tom, BTDT last year with a 1993 90Q. You're right, the ONLY way in and out is from underneath. The
job is a royal pain in the butt, but doable with patience and probably at least 10 hours' work the
first time you do it.

Right, the oil filter AND the squarish cooling unit between it and the block must come out to
provide room to work. Since there are both water and oil plumbed through the oil cooling unit, you
will have some mess (and cursing) involved.

The compressor mounting setup isn't all that bad, as there are a limited number of bolts involved.
What IS difficult is getting the refrigerant lines loose. Have plenty of various-sized end wrenches
available, and be ready to exercise GREAT patience in getting the lines loose. I had to get the
compressor as loose as practical without falling before I could even think of reaching the
connections on the lines. (Remember this when it's going back in!)

Doing this job requires changing the compressor, drier (accumulator) and the orifice valve or
conical screen. I STRONGLY recommend that before you do this job, you take the car in and have an AC
shop draw vacuum through the system and get as much debris as possible out. This will give you
better odds of a clean job.

The drier is the easy piece to reach - no real challenge there.

When you put it back together, the directions will tell you to put X number of ounces of PAG oil in
the compressor before installing it. PLEASE try to remember this (...don't ask why I urge you to do
it before you get the compressor mounted.) However, the grunting and twisting involved in getting
that stupid compressor and lines installed will surely spill an unknown amount of PAG oil...and then
how much do you need to add? I suggest you chat with the shop that will charge the system for you
and ask whether you really need to oil the compressor before installing. If it's OK to let them add
the oil with the refrigerant, it will save you slimy hands and trouble.

I'm tempted to let you go crazy like I did trying to find the d**n screen, but here's the secret:
it's at the firewall connection where the two refrigerant lines go into the firewall near the
passenger's feet. You MUST separate the connection there and remove the screen that will be found in
one of the two lines, then install the new one and button everything up. it's not impossible, just
be patient.

Incidentally, this compressor is hideously expensive - like $600 for a reman. I elected to buy a
used compressor for $150 and take my chances, and it paid off for me. You may also find that
www.BlendAir.net in Dallas can rebuild yours. They seem to be  willing to tackle most units. I spoke
with them about doing mine but the used one solved my problem. I haven't bought from BlendAir, but I
think they're worth checking out. I know they can sell the other parts needed.

Email back if needed. This post is written from memory.

Good luck, and GO COUGS!

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Al Powell
apowell at gocougs.wsu.edu
1958 Fiat 1200 Transformabile Spyder
1983 Datsun 280ZX Turbo
1993 Audi 90Q
1991 Camaro RS Convertible
1997 Chebby Blazer
1999 Chebby Blazer
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