Hello , I'm wanting to replace seals in my compressor 71 vette A6 type . Mechanic says to replace ceramic seal and he has proper tools . That is all I know at this time . Questions I have are : how many seals to replace , what else to consider on compressor that has been sitting disconnected on my dry shelf for 15 years . Compressor worked in late 80 s before restoration,however , front pully turns but seems tight or stiff . Thanks everyone .

 

Bump

 

Kendal:

I normally hang out in the C1C2 Area, and have been one of the principals there for AC repairs. I will try and answer your questions tomorrow when I have a bit more time.

A old friend forwarded me you post from the C3 Area and suggested I try and help. Look for info tomorrow.

Larry

 

Kendal:

I will answer your direct questions from above, and then provide some additional information for you to consider.

The A6 compressor has only a single front seal. Very early ones were metal seat, but later (1965 and up.....or thereabouts) they went to a ceramic seal. Most modern/current AC compressors use double lip seals, which seem to last for MANY years.

The A6 compressor has its own oil sump and oil pump. There is a drain/fill plug on the side. I would drain out all the old oil and then refill a few times (draining each time) with new oil. Spin the compressor shaft (not the clutch/belt pulley) between flushes. Compressor takes about 7 ounces of oil. If you want to continue to use R12 refrigerant, then use refrigeration grade wax-free 525 viscosity mineral oil. NAPA and other places sell this. If you want to use R134a, then I would recommend 100-150 viscosity Ester Oil. You could also use 135-150 PAG oil, but if you do, you MUST do a thorough cleaning of the entire AC system and hoses, etc. Ester will mix with a bit of residual mineral oil...........but PAG will not mix well.

If your system has been sitting open for years, or you change refrigerants, there are a number of things you also need to do. I can help you with this as needed.

If the compressor is still stiff after the oil flushing/changes above, it may require rebuilding. You can also check to see that it pulls a vacuum from the suction port in the rear and produces pressure from the discharge port when rotating the compressor shaft.

Now for some additional comments:

The ACDELCO seals (ceramic type) sold today may not provide a good compressor seal for you. They are cheap and not within original tolerances. One of our forum guys is a seal engineer and he purchased and analyzed the ACDELCO seal. He said it was not acceptable for service. And based on the failure rate I read about, he may very well be right.

I have a friend that rebuilds the A6 compressors. He is probably the best in the country, and he is also a C1C2 Forum Member. Dom builds for the best cars out there. He told me he buys all his seals from one of the big USA compressor manufacturing companies, and does not use ACDELCO. But you or your mechanic can try and replace the ceramic seal with what you can buy. 62Jeff from the C1C2 Forum did an OUTSTANDING tutorial on how to do this rebuild. We have it on the C1C2 FAQ Section. I can help you find it if needed. Jeff became a Forum Tech Contributor status from this tutorial. Good stuff!! EDIT: Here is the link: https://www.corvetteforum.com/forums...placement.html

You need to decide which refrigerant that you will use, since this determines a lot of other things you MUST DO.

Dom may be able to rebuild your A6 if needed. His son was hurt badly in a robbery attempt and Dom has spent weeks in the hospital with his son.........so A6 compressors are the last thing on his mind right now. His son remains in critical/intensive care. Four Seasons is also a decent rebuilder and sells rebuilt A6 units.............but personally I would try Dom first. You can also buy NEW A6 compressors from ALMA Products in Michigan. They use the modern double lip seal and a chromed compressor shaft for longevity. The compressor is identical to the originals except it has metric threads and internal metric machined parts. But it is a damn good unit.

Read over what I wrote, and do the oil flushes on your old compressor. Then come back and talk to me about where you want to go next. Send me a PM if I don't respond quickly, since I normally don't get to the C3 forum section.

Good Luck in getting things running again.

Larry

 

Larry:
I can find a number of 100wt Ester Oils, but no 150 wt. What would be the pros/cons of 150 vs 100 wt for a conversion from R12 to R134a? Any recs for a 150 wt Ester Oil brand/source?

Thanks,
Marc in Indy

 

Marc:

Ester 150 is difficult to find.........as you know. That is why many folks (especially those up north) use Ester 100. It should be fine. If you GOOGLE A6 compressor oil capacity or something similar you get a number of recommendations for PAG and Ester oils for R134a. Some say Ester 100 and a few say Ester 150. The 150 I believe is closest to the 525 SUS Mineral Oil the A6 was designed to use. So the Ester 100 is a bit light, but still okay.

However, one source for Ester 150 is this: http://auto.supercool.ac/product/hea...uv-dye-gallon/ With a bit more time I can find others. But this also says you may have to order it on-line..............since no one locally may carry it.

Larry

EDIT: Four Seasons AC Company (big/major AC builder and rebuilder) shows they sell the Ester 150 as well. #59012

 

Kendal:

Are you still there??

Larry

 

Thanks Larry I will pm