SirVelociraptor

As the title says I'm rebuilding the AC system in my Olds after the compressor clutch failed and violently expelled the systems contents a few months ago. I tore the whole system down, flushed out the evaporator and condenser, as well as all of the lines, replaced all of the o-rings, rebuilt the VIR assembly and filled the system with 10.5oz of mineral oil, which is what the shop manual specified as a "full charge" of oil for the system. I got the system to hold nearly -30 in. Hg of vacuum for twenty-four hours and decided today would be the day I charged it (R-12, for reference).

I tapped a can and once the system reached equilibrium with it, I started the car and engaged the compressor, only to be met with a sound that I can describe as a woodpecker if it pecked on hollow metal. I ran the system for five minutes (enough to pull the rest of the contents of the can I had tapped into the system) in hopes it would quite down as refrigerant picked up oil and cycled through the system, but it did not. I can't tell if the sound is coming from the compressor itself or the clutch, however I can say it increases and decreases with RPM. I've had no luck in finding any information from anyone else whose had a similar issue, but at this point I'm assuming I was sold a faulty reman. compressor. Before I pull the trigger on trying to get the company that sold it to refund or exchange it, which it's doubtful they will as I didn't take it to a licensed mechanic (as if there are any still around with the capability or want to work on R-12 systems) and waste 12oz of the extremely expensive refrigerant, I thought I would check in here and see if anyone might have any recommendations for things to try.

Olds64

If you've double checked the setting on your clutch and it only is noisy with the AC on the I'd say you have a bad compressor. Your clutch activated properly, doesn't it?

SirVelociraptor

I'm not sure what settings there'd be for me to check on the clutch, the unit came with one pre-installed, but yes it does engage and diesngage properly.

Fun stuff. Guess I'll be investing in a refrigerant recovery unit.

Hammerdrop

Why would a clutch failure empty the system ?

SirVelociraptor

It failed violently and took the shaft seal with it.

rocketraider

Did you drain the shipping oil out of the new compressor before installing it and the fresh oil charge? Instructions should also have mentioned rotating the compressor shaft by hand before installation.

SirVelociraptor

Correct, I drained the shipping oil and filled it with 10.5 ounces of R12 compatible mineral oil (as specified by the shop manual for a full system charge after a flush) and rotated the comoressor fully clockwise close to two dosen times before starting it.

Olds64

You can set the gap on your AC clutch, but I don't think having it set wrong would cause the compressor to grenade.

SirVelociraptor

To clarify, the current compressor is not the one that grenaded (in fact it is functioning), it is just far louder than it should be.