Amateur

Dexron 3 for both auto and power steering fluid.

Yes, it is the model compatible with the superhheat switch

Ok, the compressor is definitely the superheat switch. I understand a pressure switch simply will not fit/connect in a compressor that has the superheat switch. I am using a new superheat switch since the one on the old compressor I had to replace was old. I have disconnected the superheat switch and that appears to have stopped the smoking thermal fuse issue-why this is so I do not understand. I ran the compressor like that for 2 minutes whereas the previous times, when it smoked it was within 30 seconds. Measuring resistance of the superheat switch gave a reading of 1-1.2 with AC off Compressor green wire terminal resistance reading was 4.5, black wire terminal was 0.9-1. These were with AC on but engine off Compressor voltage was 11.96 with engine off-the terminals are uncomfortably close to the fan, so I haven't taken any readings with engine running I can't get any readings in the thermal fuse connector but that is probably user error Also tested the the engine ground which was barely 1 ohm

Disconnect the superheat switch? Would the compressor still work? Obviously risky given that there would then be nothing to stop the compressor burning out if refrigerant gets low. I tried a different thermal fuse, but all that did was take a few seconds longer to start smoldering. The system is partially charged with refrigerant, because the shop didn't want to keep charging with a smoking compressor-they were concerned enough to stop.

The thermal fuse I've just noticed has a shorter middle prong than the previous one and is shorter than the 2 outer prongs. I'll try another fuse with the right prong size over the weekend, hopefully thats all it is...

Thanks, compressor has good clutch and was filled with correct amount of new PAG oil for running on R134 as I can't get R12 where I am. I just don't get why it would smoke at the fuse.

Car is a 1976 Cadillac Fleetwood Brougham. I've just replaced the compressor and superheat switch with a rebuilt A6 and changed out the dessicant bag in the VIR with new o-rings. When it came time to recharge, there was some difficulty getting the compressor to turn. I suggested replacing the thermal fuse which the shop did (although the fuse hadn't stopped the old compressor from seizing but the fuse was some years old so worth a try). This got the compressor turning as refrigerant was added however within a few seconds, the fuse was smoldering and there was a burning smell. Shutting off the AC stopped it. The fuse was almost too hot to touch. The wires have no obvious fraying or chafing etc and much of their journey is in a protected plastic conduit wrapped around them. What could be causing this? The Compressor is getting current and voltage, its the standard A6 direct replacement. Could the shop have installed the thermal fuse the wrong way round? (although wouldn't that result in the compressor not turning and therefore no smoldering?) Bad superheat switch? Electrical issues aren't really my thing Thanks

Thank you very much. So the second wrench is simply held in place on the VIR unit or do I turn both wrenches at the same time in the same direction?

I have to take the VIR off to replace the dessicant bag after the compressor burned up. Car is a 1976 Cadillac Fleetwood Brougham. It looks like there are 2 nuts, but one is part of the VIR unit itself (an old one left in a box with the car by previous owner has this nut too and its not loose as I thought it would be if its been removed from the car). That nut has threads inside it. I've tried PB blaster on the hex nut on the refrigerant line but can't get it to move. I presume it follows the 'lefty loosey right tightey' adage which would mean I turn it towards the passenger side wheel? Is there some trick I'm missing for this one? I haven't come across 2 nuts joined together like this before. Someone must have removed one of these things before and can advise?