Recommended A/C Upgrade to Use R134a?

[DJ_Baar]

A/C Compressor clutch is shot (new project) and suspect system needs complete upgrade ('67 Chevy C20 LB Camper Special). Recommendations on best way to fix this?

[1972RedNeck]

Originally Posted by DJ_Baar

A/C Compressor clutch is shot (new project) and suspect system needs complete upgrade ('67 Chevy C20 LB Camper Special). Recommendations on best way to fix this?

Personally, I would source a USA remanned stock compressor and adjust the POA valve for R134 pressures.

[davepl]

Stock parts work for me! I'm running a reman stock style compressor with the system previously converted for R-134 and, other than a leak I'm chasing, it all works nicely.

If you're not concerned about appearance, I'd likely consider a more modern style aluminum compressor. But the stock unit works for me.

[DJ_Baar]

Here's a picture from under the hood & interior. Truck is all original with factory air and power brakes (drum), except change to engine (replaced 327 with 350).

[F.A.A.benny]

You can get a reman a6 compressor pretty inexpensively. Just might have the oil misting from the shaft seal before too long. If that isn't an issue, then just recalibrate the poa valve for 134a. If you don't wanna deal with the oils misting issue then you can go with an aluminum a6 replacement compressor. Most commonly known as a pro6ten or S6. You can get those for around $300. Also, should get a new drier, O-rings, flush the system and add pag oil. If you don't completely flush the system, go with ester oil as its compatible with both pag and mineral oil. Someone will probably chime in though, saying not to use ester because it absorbs moisture. Its what we used where I use to work.

[davischevy]

I have two trucks with all original components running 134A that work great.

One truck had the POA recalibrated and one truck that doesn't. The one that had the POA recalibrated works somewhat better, but the one that isn't recalibrated works plenty well.

[davischevy]

I meant "original Style" components. I have changed some hoses, compressors, valves, dryers etc.

[flipbr61]

What are the gauge pressures thank you. Phil

[DJ_Baar]

Compressor clutch is shot, so no pressures ... was looking for best route to fix this for new Freon, etc....

[davepl]

Originally Posted by davischevy

I have two trucks with all original components running 134A that work great.

One truck had the POA recalibrated and one truck that doesn't. The one that had the POA recalibrated works somewhat better, but the one that isn't recalibrated works plenty well.

My truck was converted before I got it, but I had a leak in that little valve that looks like a plumping part 90-degree with the probe that goes to the discharge tube to moderate expansion (expansion valve? not sure).

What needs to be recalibrated? Is there any way to tell if that was done when they did the original conversion? Or could I just have a shop "adjust" my current one somehow?

Doesn't sounds like I -must- do anything, but that you got better results with a reconfig, so am curious.

[F.A.A.benny]

The poa valve is whats recalibrated. With the gauges on, if the low side only goes down to 30psi then its calibrated for r12. There are write-ups on recalibrating it for 134a. If you don't want try it yourself, I can recalibrate it for you. I do it all the time for the poa valves that I rebuild.

[LEEVON]

I am running a Pro6Ten compressor from Old Air on the original system which has completely restored. The compressor is lighter, more efficient, does not leak and cost about the same as a new A6 so it's a no-brainer in my opinion. If you're going to use the original system, it's important to make sure all of your vacuum hoses and connections are good, cables freely operating and flap doors sealing. I used R12 only because I have a good supply and it works great. R134 conversion with the POA adjustment is good too. The only thing I am missing is the factory idle compensator, so I have run the idle speed a little higher during the summer.

[1972RedNeck]

Originally Posted by F.A.A.benny

You can get a reman a6 compressor pretty inexpensively. Just might have the oil misting from the shaft seal before too long. If that isn't an issue, then just recalibrate the poa valve for 134a. If you don't wanna deal with the oils misting issue then you can go with an aluminum a6 replacement compressor.

That's why you have to find one that is rebuilt right here in the United States of America by Americans. They run for years with no problems.

[F.A.A.benny]

Actually they all eventually mist oil. Its in their design. Gm knew about this way back even before these trucks rolled off the assembly line. Some GM models even had a cover on the clutch to catch the oil that was slung. Also interestingly enough, the Pro6ten/ S6 aluminum version of the Frigidaire A6 (Made here in the US) that a lot of guys are so fond of, is made in China.