When I installed air conditioning in the Miata I started by rebuilding a used compressor with a gasket kit and new front pulley bearing. There were not many references, hopefully these photos are helpful for anyone else rebuilding their AC compressor.
The first replacement pulley bearing I ordered was the wrong size, I recommend measuring the ID and OD of the bearing and finding an exact replacement. I’m not sure how many variations there were across different years of Miata air conditioning compressors.
Not sure what the purpose of that felt pad is, but I kept it installed on my compressor.
The sections of the compressor were hard to separate after years sealed, but also because some of the bolts holding it together were not obvious. Two sneaky bolts are labeled in the image above.
This projects was very messy, compressor oil everywhere by the end, even with the plastic sheet.
Some percussive force was required to separate the compressor sections.
Some black engine enamel was spayed over the surface rust on the main compressor housing.
The bearing went in the freezer overnight to shrink its diameter a bit before pressing it into the pulley.
The small washer keeps the spacing of the compressor clutch in spec for the electromagnetic to engage the clutch.
Later when replacing the power steering pump belt tensioner a 10mm x 1.25 tap was used to clear out these thread. They were crusty after 25 years of exposure on the side of the motor.
The compressor bracket also got a fresh coat of black engine enamel. The top-front corner needed to be shaved off later to clearance the new Flyin’ Miata belt tensioner.
This compressor rebuild job was successful and has been working perfectly without leaks since 🤞 (as of Feb 2024). The clutch was pretty worn on this old compressor, so it does have some occasional slipping and squealing. I bought a replacement clutch to be installed in a future post.