OK guys here's the deal. 1990 Iroc with the original a/c (still r-12) was working fine and then poof....nothing. My clutch won't cucle at all, no mater what setting....now I know that having low freon can cause the a/c not to cycle but I don't think thats it. I was working on my fans and something smoked on me...couldn't tell what....and noticed the next day I wasn't getting any cycling of the compressor. I'm suspecting my a/c pressure switch....if I unplug it and jump the two terminals my compressor kicks in...so I know there's no power interuption...all fuses are good. Any way of testing the switch itself? And if it is bad....can I replace this switch myself...or will I loose all my expensive R-12? Thanks guys.

 

From the sound of it you don't have much r12 left. Hook up a manifold set an see how much pressure is in the system. I don't recall how much pressure it takes to close the switch. You don't see too many of those go bad.

 

I think it should be around 35-40PSI, with the compressor engauged or jumped.
You might be able to find a cheap pressure tester. It looks like a tire tester, but with the bigger opening. Now I'm not promising that, cause they (EPA) have realy made it a turd to get the cheaper R-12 test equipment.

You can replace the pressure sender yourself, but you'll need to have the freon taken out professionaly. You should be able to get a claim ticket, to get your freon back plus a small fee when your done with the work.

I'm going to go with 'cp87GTA', I bet you strung a leak.

I preach this alot, but you might look into a blend like R-414B, instead of replacing the R-12, cause the crap is getting to damn expensive.

Ron

 

ok....think a fuel pressure tester would work??? If so...do I connect to the high end or the low end? Thanks

 

You'll want to test the low side. As far as a fuel tester, I dought it(probably has different size, and pitch threads).
I had two types of testers for R-12, one that accualy screwed on there, and one that had a plasic stick that would slide out (like a tire tester).

Here's a thought, if you cant find a R-12 tester. Get a R-134a adaptor that screws on your R-12 low side, and a 134a tester. The 134a tester are easy to get. I think Pep-boys carries a bunch of testers, and adapters fittings for 134a.

Ron