I was thinking I would leave everything installed, but disconnect the lines from the compressor then suction out 2 ounces with a syringe. What do you think?
Hmmm. I find it hard to imagine that 2oz of excess oil is causing the issue. It sounds like you have a loss of capacity which can be caused by several things. One is fouled condenser and or evaporator. Two is insufficient charge. Three is a weak compressor - possibly leaking piston rings. Four is stuck reed valves at the compressor. Five is stuck expansion or POA valve. If we are operating on the theory that the excessive oil is occupying space in the system and causing excessive pressures my sense says it would take a lot more than 2oz of excess oil. So far as pulling some out of the compressor sump, I don't think that will have much effect since the circulating oil in the system is separated for the most part from the oil in the compressor by the piston seals. If compressor oil is getting by the piston seals then the compressor needs a rebuild and that will likely turn out to be the culprit. The purpose of the circulating oil is the lubricate the reed valves.
