how do u tell if the compressor is bad. neva been able to use A/C because of no r12 but compressor is turning slow and looks like its havin trouble??
Easy steps- With the engine off, see if you can turn the compressor by hand. Not the pulley, the front part with the three holes in it. That's the shoe, which gets pulled in when you engage the electromagnet. If not, the shoe on the clutch's springs are shot. If charged, it won't be easy to turn. Check the system pressure with a pressure gauge (tire type is good enough) that goes above 100 PSI. A fully charged system has 100+ PSI in it when it's not running. Look at your hood. Do you see a streak of oily residue across the hood, in line with the compressor clutch? That means a bad seal. It's turning, but slowly, not at engine speed? Clutch is toast/compressor has no oil in it. Any one of these conditions is indicative of a bad compressor part. Note that the clutch, seal and shoe can all be replaced, but you have to ask the question- 'Is it worth only doing part of it, when all the rest of the parts are that worn?". I wouldn't, but then I'm a picky old fart.
Nice SteeveeDee, Really good breakdown of compressor problems, sir. I'll disagree with you on this, though: Look at your hood. Do you see a streak of oily residue across the hood, in line with the compressor clutch? That means a bad seal. Compressor shaft seal oil leakage was normal and expected on all A6 compressors due to the design of the ceramic shaft seal. It varied widely in amount, but GM claimed that any oil leakage was "normal" as long as there was no detectable refrigerant leakage. The oil stripe on the hood blanket and all over the engine itself was part of the Four Seasons Climate Control option. At no extra charge. Today, that 2 piece ceramic seal can be replaced with a double lip neoprene seal, which will eliminate the oil leakage.
need A/c guages static psi will change some with ambiant temps run your a/c and watch guages r 12 should be around 28 -38 high around 225-250 tops depending on outside trmp . Sound like high side is very high if compressor is slowing down , possable over charge ?
thanx for relpies guys. im waiting on a buddy to get back from outta town to look at it.i was told maybe low freon would keep it from turning?? belt spins just not the frontal part that is supposed to.i can turn it pretty easily with hand tho.(sorry guys i kno nothing about this but buddy from outta town is heat and air guy so he will....and he has good supply of r12)
OK, lsrx101, that oil leak info is new to me. I always thought that if there was oil, the refrigerant was leaking, but in retrospect, I can accept that the refrigerant would stay if the oil provided a good film. I learned something today! On the low refrigerant condition. Depending on what year you have, the clutch won't engage at all if the refrigerant is low, because there is a fuse (out near the compressor, under the hood) that will blow in that case. I still have some of those in my AC service stuff. Probably no good- I went to work as an engineer in 1984, and I don't remember the last time I replaced a thermal limiter fuse. Also, your high side can get as high as 400 psi if you are standing idle and running the AC in hot enough weather. I used to put a big fan in front of the radiator to help cool the car in those conditions. That was for impatient customers. If they left the car, I'd let it cool down and restart servicing it. On a day that's 107F in the shade (gotta love California), it gets pretty hot under the hood, especially when the AC is adding all that waste heat to the cooling system.
