On 7/8/2012 10:14 PM, J Stewart wrote:> Then, if that is true, the
compressor Bus Depot just sold me as
 > compatible with either R12 or R134A isn't-the label on it says "mineral
 > oil" I'm still confused here and don't want to ruin an expensive part!

I think you want to empty any oil that's inside, and preferably flush
it. AC flush should be available at your FLAPS. Since your system was
upgraded, it probably uses ester oil, so you'll need to put some of that
in (Ester is compatible with both mineral oil and PAG, and compatible
with both R12 and R134a, so it's the "universal" choice). The Bentley
should say how much sits in the compressor.

The new compressor should have come with the right amount of oil, so you
could theoretically measure what comes out. But that assumes it was
properly filled, didn't lose any during its obviously long storage, you
can drain almost all of it, and there's not a large amount which comes
out with the flush.