I have a customer with a copeland 3RA compressor for a fresh seafood case that busted a rod and locked up around 4 months ago. I got the compressor started and it ran for another week on one piston while I ordered parts. I put new rods, pistons, and a valve plate in it and new oil filled to 3/4 on the sight glass.
I don't know what oil level the pump was running at pre-rebuild as the sight glass was too dirty.
I assumed the low velocity of the compressor running on one piston would result in an oil logged evap and that the rebuilt compressor would be overfilled once the oil came back and I would need to drain some. However, just the opposite happened. The oil level dropped to 1/4 in the sight glass and stayed there.
what could be an explanation for this?