AC decompression diagnosis

[Tora]

My AC was blowing cold and working fine for 10 the years of light use I put it through (not much occasion in the Northwest aside from a couple months in summer). I recently did an electric fan conversion with the OEM temp sensor and was running my car in the driveway with the AC on full blast to get the engine temp up high enough for the electric fan to kick in. Suddenly, I hear a LOUD hiss come from somewhere in the engine bay. I shut the engine down and after 5-10 seconds the hissing stopped.

Needless to say, my AC stopped working after that.

I had Jiffy Lube try to recover all of the R12 they could out of it, and it took FOREVER on account of a leak somewhere in the system. While the system was being sucked dry, what looks like a pressure release valve on the back of the drier was making a hissing sound and sucking air into the system. Eventually, the machine shut off and showed that they recovered maybe 0.1 pounds of R12.

So, I'm hoping that the problem with my AC is just a bad drier; a cheap part that should be replaced with a recharge or retrofit anyways. However, the compressor clutch no longer engages when I turn the AC switch on. I'm not sure if it was engaging before the leak, but it seemed to be blowing cold. Does the clutch only engage when the whole system is working properly?

[allencr]

IIRC system has a low pressure switch.
AC's dash button blinking?

[Tora]

Not blinking. The button stays lit.

[Tora]

Anyone have any experience working on the AC in a GTS? I've got a new, cheap drier, and I'm wondering if replacing that and the O rings might be enough to revive my system or if it'd be a good idea to just go ahead and replace the more expensive ($300) compressor.

[allencr]

Wouldn't replace the comp. without reason, like its extremely high pressure actually caused the failure & blew up the drier, or it wasn't previously working, or its seal was leaking too much. Much oil residue by its clutch?