A/C Help

[tkeiser1]

I need help to resolve a problem I've been working on the past two summers. I have a 63 Riv and I'm trying to get the A/C working. The expansion valve was clogged so I bought a new one. Unfortunately, according to Jim Cannon, all parts manuals have the same expansion valve listed for all big 63 buicks, but the Riv actually had a different one. The two main connections on the replacement valves are different sizes, although in the original they were the same. I had an AC company make me an adapter. But they said they can't help me with the following problem. The third connection, the equalizer line, has a male connection on the tube, whereas the original had a female. Does anybody have any suggestions for how to join these two lines?  (see pics)

[Turbinator]

You might a well check the STV valve for functionality. Most people buy the electronic switch that by passes the STV operational function. Since zi rebuilt 3 STV I finally gave in. 
I just bought the expansion valve from Old Air in Texas. Works good. I worked on the 63 AC for a long time. Ended up replacing everything J could. Even had the hoses rebuilt. Mr Jim Cannon is most experienced on this 63 AC. Are all your vacuum actuators working? Vacuum hoses all in good shape? Just trying to save you one ounce of aggravation.

Turbinator

[tkeiser1]

The vacuum actuators are working, but I don't know about the STV. That was going to be the last thing on the list after I got the connections right. Fill me in on the bypass switch. I'm not familiar with that. 

[Nick57]

I have that same expansion valve sitting on my work bench never to be used.  Old air products in Texas has the correct expansion valve its triple the price but it works with with no adapters needed.  I personally bought two after my first brand new compressor was junk out of the box and filled my system with metal shavings.  I included the link below for the the STV update switch.  I have a new Alma compressor in my car and I talked to an engineer at Alma and he said the clutch they use would be fine for cycling.  I have not noticed any issues with mine so far.  Biggest pain about installing this is that you have to get the probe up on the outlet of the evaporator and that involves taking the case out form under the dash.  Also make sure that your lines and muffler are thoroughly flushed  I ended up having to eliminate my muffler after the compressor went bad because I couldn't fine a replacement muffler and it just wouldn't flush clean.

 

https://www.oldairproducts.com/product/50-2500p-stv-update-kit 

Edited September 20, 2020 by Nick57 (see edit history)

[Turbinator]

Nick57, I’ve had a problem with AC muffler allowing oil to puddle up in the line and not allow the system to charge. This puddling was discovered twice when flushing the and evacuating the system. I also have the Alma A6 ( newly manufactured).

My current AC problem is a leak. The leak could very well have been at the STV where the update takes place. I went ahead a rebuilt the STV again for the electronic switch. Can you hear the clutch cycling off and on with electronic switch? Than you

Turbinator

[Nick57]

It is so smooth unless you are really looking and listening for it you wont hear it.  I can only notice it when the switch itself clicks, under the hood you can barely tell unless you are watching the compressor clutch waiting for it.  I mounted my switch on the bottom of the evaporator box using an existing screw hole so there's no extra holes drilled you can hear the click inside the car.  I would probably eliminate the muffler if its giving you trouble.  I notice no noises that are loud from the system and have had 3 other cars with A6 compressors with no mufflers that worked just fine.

 

-Nick  

Edited September 21, 2020 by Nick57 (see edit history)

[tkeiser1]

Very helpful info, Nick. Thanks.  

 

Tom

Edited September 21, 2020 by tkeiser1 (see edit history)

[Jim Cannon]

The A/C muffler was an early production add-on change to the '63 Riviera.  The first models produced did not have it.

 

Someone decided that the A/C was making too much noise.  The muffler provides a volume into which the hot gas pulses can be smoothed out.  Later GM A/C systems used a much smaller cylinder mounted to the side of the A6 compressor.

 

The A/C will certainly work OK without it. The connections of the hose to the muffler on my car are screw clamps. Not as good of a seal as an o-ring, so a potential leak point.  Better to just eliminate it.