A/C compressor clutch

[MTBLAZER89]

Just poking around under the hood of my 89 crew cab. I notice the plug is disconnected on the compressor. I hook it up and flip on the air, and the belt just starts to squeel Can you replace the clutch on the compressor without opening the system? I idon't know if the R-12 is even charged, but if it is I would like to just try and replace the clutch. Can a shop check the level of refrigerant in the system?

 

[goldwing2000]

If the belt squeals when you turn the system on, the problem is not the clutch. Your compressor is probably seized. And when that happens, it usually dumps metal shavings throughout the system, so it will have to be flushed after it's repaired and before it's recharged.

No, a shop can't check the refigerant level, per se. They can check the system pressures and tell you if it's low but not by how much. But they can't check anything if the system is nopt operating properly.

Lastly, if you're going to be changing the compressor, you might as well change over to R-134a (or some other refrigerant). R-12 costs a fortune these days. It would probably cost you at least $100 in refrigerant (maybe more) to keep the system on R-12.

 

[MTBLAZER89]

Yeah I guess i didn't think about that obviously the clutch is working huh Yeah I will swap over to 134. I had a shop give me an estimate of $250 so that doesn't sound too bad.

 

[eclipse]

250... is that with a new pump, changing it over to 134a and a system flush out? That ain't bad

 

[MTBLAZER89]

No that was before I knew the pump was screwed

 

[spoolnaround]

I think I still have the pump that was on my 74, if I remember it worked. If I still have it your welcome to it.

 

[MTBLAZER89]

Will the pumps interchange? I was thinkin about taking the one off of my K5, but it's serpentine. If so I'll prolly take it off your hands.

 

[goldwing2000]

If the belts are the only difference, you can just change the clutch pulleys and it will switch over fine.
If you do that, be sure to set the air gap right.

Before you go tearing things apart, make sure the compressor is bad. With the engine off, try to turn the compressor by hand (the front of the clutch assembly is fixed to the compressor shaft). It should turn easily.

 

[MTBLAZER89]

If the belts are the only difference, you can just change the clutch pulleys and it will switch over fine.
If you do that, be sure to set the air gap right.

Before you go tearing things apart, make sure the compressor is bad. With the engine off, try to turn the compressor by hand (the front of the clutch assembly is fixed to the compressor shaft). It should turn easily.

Ok what is air gap?

I tried turing the front inside part, and it's stuck really good.

 

[goldwing2000]

Ok what is air gap?

I tried turing the front inside part, and it's stuck really good.

Compressor's definitely shot, then.

Air gap is like spark plug gap for your clutch. It's the space between the drive plate (middle part with the belt pulley) and driven plate (the outer part). If the air gap is too large, the clutch will not engage properly (or at all) and may slip and overheat. If it's too tight, the clutch may not disengage fully, which will cause the compressor to run constantly and the system to over-pressure.

Also, be sure you change the orifice tube and flush the system before any new components go on.