1969 Cadillac Sedan DeVille

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Cusser
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1969 Cadillac Sedan DeVille

Post by Cusser »

My friend has a 1969 Cadillac Sedan DeVille which has been in his family forever; nothing has been done to the AC (still R-12) in decades. He reports that the AC only cooled "mediocre" in 90F weather last summer, figure some refrigerant loss over those years.

However, his immediate issue is that his AC-power steering belt came off and was making noise, did this without using the AC. I went over to take a look-see, and his AC clutch pulley bearing is very rough, the PS pulley turns normally. I advised him just to get a shorter belt and bypass the AC compressor for the time being, so the Cadillac would be able to be driven. The compressor drive plate itself does turn with what I consider typical force, so the compressor does not appear seized. The system does have R-12 pressure (I didn't measure, didn't have gauge set with me).

The compressor is Frigidaire Model 6550133, code 060171 (may be a serial number), states 3.75 capacity; may be an A6 type. He called a dedicated AC shop, the owner said he cannot get R-12; I even see that Ebay has banned sale of R-12 these days.
Question 1: is the 1969 Cadillac Sedan DeVille a good candidate for a conversion to R134a?

Question 2: if the AC clutch bearing or AC clutch assembly can be replaced readily, would that be a decent path? I understand some R-12 would be needed in this instance to try to improve performance.

Question 3: We'd be open to all suggestions from you professionals. Thanks.
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Re: 1969 Cadillac Sedan DeVille

Post by Tim »

It's an A6 by your part number. Hub/bearing fail all the time on those. Resurface the clutch pulley, bearing, and hub. A6 will always leak for the most part. If it still has some refrigerant. I'd do the clutch rebuild first. Swap oil and accumulator and see what you get with R134a. The old caddy should have a large condenser. But in AZ, doubt it will cool great when it's 115.
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tbirdtbird
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Re: 1969 Cadillac Sedan DeVille

Post by tbirdtbird »

Cusser, our wonderfully devoted EPA forced eBay to ban R12 sale.
You may still be able to find it on facebook marketplace.
Eventually, tho, he will end up with 134.
I would bite the bullet and do the conversion. You will have to adjust the POA valve, or get one from eBay that has already been adjusted.
We have a quality A6 rebuild place here in Texas (Yellow Rose) which is not far from me. Change the condenser over to PF, they are available, I am sure Tim can help. Dave
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Re: 1969 Cadillac Sedan DeVille

Post by bohica2xo »

Cusser:

A few paths to take, depending on the use the car sees.

1 You could keep it R12. We know the refrigerant is harder to get, and that the A6 seal design will always pass a little oil. Along with that oil a little refrigerant is lost. If the car sits a lot the seal seems to leak more. The up side is the POA valve stays in place, the oil is good to go, and you add expensive refrigerant occasionally

2 You convert to 134a. A flush and different oil. The POA will need recalibration. It will still leak oil and refrigerant, but the refrigerant is less costly - and is headed for phase out like R12 was.

3 You convert to the R290 /R600 HC blend. The oil can stay, the POA can stay. There are some that will argue against any HC, but now that 1234a is in wide use the argument begins to fade for many. The stuff works. It is flammable. So is 1234a

So is this a family heirloom? A parade car? A daily driver? Pebble Beach car?

As Tbird has already pointed out, swapping to a large PF condenser always helps. If there is no need to keep the car 100% original, the better condenser is always a good plan

The "slap a sanden on it and toss the POA" plan always cools poorly here in the southwest. Like roll the windows down in August below 65 mph bad.

I can probably find you some R12, do you have your 609 license?
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Re: 1969 Cadillac Sedan DeVille

Post by Cusser »

I will pass on the suggestions to the owner.

The car is a family "heirloom", in pretty nice condition for its age, and not a show car.

Would anyone link good instructions on how to replace a compressor clutch on this, like with any extractor/installer tools? I have pulled AC clutches on about 3 vehicles in the past, and for my 1988 Mazda B2200 truck (Sanden SD-708) I had to make some tools, the loaner set from the parts store didn't help at all.

For a 1998 Nissan Frontier I just had to purchase three 5mm hex head screws to extract the drive plate.
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Re: 1969 Cadillac Sedan DeVille

Post by bohica2xo »

Cusser:

The A6 and other GM products have a pressed on clutch hub. The clutch service takes a special puller, then another puller and support to get the pulley off. Here is a video:

https://www.youtube.com/watch?v=URqFd3KkSRY

I doubt you want to buy the tool kit. Having said that, the guy in that video is in Tucson. He can probably service that bearing for you.

How often do you get to Las Vegas?
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Re: 1969 Cadillac Sedan DeVille

Post by Tim »

Cusser, I probably still have my GM tool service kit if you need some loaners. I know I have the Mastercool Master kit.
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Re: 1969 Cadillac Sedan DeVille

Post by Cusser »

Thanks, all. I will pass on your responses to him; he lives in Prescott, but his two kids live in Phoenix, so he might be amenable to a repair shop here. I'll let him make the decision, don't think I should get involved hands-on other than bypassing the compressor with shorter belt so car is driveable. A fellow senior softball player in Prescott area has a well-equipped garage with a lift, and I think we'll ask for his input and experience as well. He helps his friends as a hobby; I have never yet used him (don't want to go to the well too often) and have even given him an old shop press, and he's a nice guy.

Advanced Auto Air in Prescott Valley was the place that said they couldn't find R-12. Last time I used them, Smart Auto on N. Cave Creek still did R-12, and I heard on Mark Salem's radio show that Salem Boys Auto in Tempe does R-12.

Myself - I don't have a 609 license; I have only one vehicle (1988 Mazda truck) that still is on R-12, and I have a few cans saved for that from the old days.
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Re: 1969 Cadillac Sedan DeVille

Post by tbirdtbird »

Cusser, you can get your 609 here:
https://ww2.epatest.com/

The test is really not that hard, you already know at least 75% of the answers and further, you are a smart guy and it is open book. For a guy like you, it would prolly be a good idea.
Might even consider getting your 608 in case you want to buy residential refrigerants like 410.
Now, point in fact, technically you do not need a 608 to purchase 410, but most places do not know that and demand one anyway. Again, not a hard test. They are mostly concerned with you knowing how to properly handle and dispose, ie there is no more venting to atmosphere, as you know.

And Brad, as far as 1234yf, we both know soon enough that one will be supplanted by yet another one, so that everyone has to re-tool yet again. Somewhere, someone at a higher level has turned refrigerants into a revolving door scheme
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Re: 1969 Cadillac Sedan DeVille

Post by JohnHere »

Some additional comments about R-1234yf...

Last summer, I purchased a new Toyota 4Runner Limited that has the above mentioned refrigerant, my first personally owned vehicle that didn't have either R-12 or R-134a. The best it would cool for me on a hot summer day here in the humid South (~90°F) was in the high-40°F range at the center vents after driving around for quite a while—30 minutes or longer. This performance is noticeably warmer than my other vehicles that would quickly pull-down the center-vent temperature into the high-30°F range even on local roads.

So I took it back to the dealership last year under warranty. They recovered the charge and found it had the approximately correct amount. Subsequent testing revealed that they could get it to produce only 46°F at the center vents and typically higher than that. To me, temps like those aren't acceptable, especially for a brand-new vehicle.

Of course, it's too cool to test it now. I'll have to wait until the temps climb to 80°F or above. Then, I'll see what it does. But so far, I am not at all encouraged by this new refrigerant.
Member – MACS (Mobile Air Climate Systems Association)

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