Help needed troubleshooting my new AC system

hi. I will start by saying I am an idiot when it comes to AC systems.

There, now the issue.

I purchased a complete 134a conversion kit and pro6ten compressor from a reputable company.

I installed everything.

I initially tried to charge with freon but could only get the system to take 1 can.

Someone said I needed to pump down my system first.

I bought a vacuum pump and pumped it down first for 10 mins, then added freon.

It took 2 cans, but stopped with the third.

I have ~120lbs pressure on the high side, don't know low side because I apparently broke my low side gauge somehow.....will get a new set tomorrow

I am getting 12 volts to both pins on the leads to the compressor when the AC is turned on, but I do not ever hear my compressor cycle.

My questions:

Should I get 12v to both leads?

What are my next steps with troubleshooting?

 

One lead is ground the other is power. If your near North Fl I'd be glad to help you with it

 

Well, I will start there. Must have an issue in my harness somewhere. I have 12v to both leads? Will update once I fig it out.

And nope....in Albuquerque New Mexico, but thx for the offer.

 

If you are working on one of the 1972 Buicks, they have a fuse-like deal on or near the compressor. It's called a "thermal limiter", and like a fuse it's cheap to buy. If the charge gets low, it blows and won't take a charge unless it's jumped or replaced. I'll look for a pic....... http://shop.advanceautoparts.com/p/...1022_s__vi__&gclid=CLe_tLeA28cCFdCRHwodG7sNng

 

Ha. Good timing. was just going to post "what is this thing?"


So this fuse does not enable voltage to go from one pin to the other?

 

I honestly have not seen or worked on a 72 up AC for a really long time! I'm not sure if that's the right plug. I know 72 up uses the fuse, I think it has a superheat switch also that takes a single wire at the rear of the compressor. There should also be a ground wire around the compressor. I know zip about converting that to a Pro6Ten.

 

Well, the Pro6Ten has a 2 prong female connector that is supposed to plug into the 2 prong on our harness.

The instructions also said to wire the new pressure switch in series with the wire on the left side of the prong.

Bottom line, my compressor won't cycle and I can't figure out how that thing would cycle without at least one of the prongs being a ground - which it is not. Once the AC system is turned on, both sides show 12V.

Does anyone have any insight that has wired up a 72 with a similar system? Could someone check to see if both sides of their plug have 12V when AC is on at max?

Would love to get this thing blowing cold tonight. Leaving to a car show 3hrs away with the family tomorrow......

 

Well, I ended up wiring both sides of the original harness plug into one female plug. I then made a black ground wire with female plug. I plugged the wires into the pro6ten compressor and CLICK it started working. Got the system charged and drove today with AC in the car for the first time since purchase in 1989.

Problem was then that I could not get it to shut off. I discovered that I have 12v at both sides of the original plug at all times when key is on, regardless if AC is on or not. I suspect that I may have a bad AC switch. I wired in a manual toggle.

I still want to figure out how it is supposed to be wired correctly, but this works for now.

 

That is how mine came from the factory

 

I was at a show over Labor Day and checked a friends GS. His has a conventional plug and wiring set up, one side positive, one negative. Only 12v on positive side when AC switch is in on position.


Color me confused.......

 

I've yet to reinstall the AC components back into my GS since the motor replacement. I'm in Mount Dora. So, is the offer of help with AC work good for me if I drive up to Ocala? I remember meeting you at that shop opening over on the coast some time ago. I had my WE4 with me that day.

Don't mean to hijack so, go PM if you like.

 

I would sure appreciate if you would please take photos of what you have done. Would help my situation if I could see your solution. Oh holy cow some of you on this thread are in FL... woo hoo! Any of you passing through Debary? I could use the AC help!

 

Wow I grew up in Debary and that's where my parents live. Next time I come back home I'll shoot you a PM and try to meet up with ya. And thread revival because I'm researching putting my AC back in my car haha

 

That plug is NOT the thermal Limiter. The thermal limiter has 3 spaces on its plug. That is the compressor clutch plug.