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Replacing A/C compressor in 98 Civic

I have a 98 Honda Civic. The A/C compressor was bad (the clutch froze up). I replaced it with a compressor that I got out of a 92 Civic. The compressors seem to be virtually identical. Before I make the final connections and start it up, I need to figure out what kind of oil to put into the compressor (I dumped the old oil out so I could put in new oil). I have a bottle of PAG 46 oil. Here is my question: In researching the type of oil, I found out that in 1992 the A/C system used R-12 (and thus mineral oil in the compressor?). Will I have any compatibility issues with the PAG oil if I don’t first flush the compressor somehow? Will this compressor create any issues with the system of my 98 Civic? In other words, is there any reason I can’t just fill the 92 compressor with PAG 46 oil, connect everything, charge the system with r134 and be good to go? Or am I risking a major problem by doing that? Thanks!

If I were doing this compressor swap, instead of using PAG oil I would use ester oil. PAG oil is used only in R134a AC systems. But ester oil can be used in both R12 and R134a AC systems.

Tester

Ok - thanks! At Autozone I only saw ester oil in a medium viscosity as opposed to the low viscosity of the PAG 46. Do you think that’s a problem? I could probably hunt around for a lower viscosity of the ester oil. Thanks again for the tip!