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AC compresser


Well-known member
Feb 9, 2001
Shreveport, LA
1981 silver/blue: two tone
When the air is on the compresser cycles pretty often. When it cycles, the clutch makes are good racket. I have checked the belt and it is loose, so I tried to tighten it. When I pulled back on the compressor to tighten it, it turned toward the firewall. This misaligned the pulley. Do I have some different kind of bracket on this or what? I am obviously not a professional, but this should not be that difficult. What should I look for.
compressor turn/shift

You didn't say what year yor pride and joy is... or if it has the A6 axial type compressor (cylindrical; about a foot long by about 5" diameter). If it's an A6, check the large bracket that mounts to passenger exhaust manifold...it is attached to manifold by at least one stud that also holds manifold tight to head. This stud could be broken... allowing bracket to shift but manifold remain tight. Upon disassembling my motor for rebuild, I found a compressor stud ALMOST broken from years of heat & vibration. This is hard to see and get to as it's underneath compressor and at ex manifold...whatever, do let motor cool first:( ! Hope this helps...let us know how it turns out. Jack
It is a 1981. It is not the A6. The compressor is about 6-8 inches long. thanks for the input
R4 radial compressor

Your 1981 probably has the R4 radial compressor... I don't personally know the R4's bracketry... but I'd check all brackets and bolts no matter what model year / compressor. Again, look for broken or missing bolts and studs... also possibly cracked bracket(s). My bet is on a broken or missing fastener...hope it's just that.
You were right. After some investigation, I found that the bottom bolt that went completely through the compressor was missing. I am in the process of replacing it and that should do the trick. Thanks
:) :)
If your compressor cycles on and off very often, you might be low on freon.
loctite & R134a

Great news on missing bolt! Try some LocTite thread locker on those fasteners. Safe bet Gid's right about low freon...could be bad pressure switch too...or both. Whatever, you sure need some air down there in bayou country! If it turns out you need freon, now's a good time to convert from expensive R12 to the current R134a...that is unless you've got a stock of R12...if so, be my pal (lol). Please, whatever you do, stay away from those "cheap-miracle replacement refrigerants" as some are quite dangerous and are little more than butane. I bubba-bench-tested a flea market hawker's "replacement" freon for flammability...laid an open can with an ounce in it on ground...held lighter to it (it was already struck) and...WHOOM! Consider R134a...you can get it anywhere for $5 a pound/can...no license required...and it's a safe & proven entity.

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