My parents' 2014 Chevrolet Spin Diesel compressor shaft seal was leaking. We replaced the seal and shaft's ball bearing (located between the seal and clutch plate), add about 44mL PAG oil into the compressor (before compressor disassembly there is almost no oil in it), reinstall the compressor, vacuum, and then fill AC system with refrigerant. Leaking problem gone, AC seems worked properly for a few hours of operation, and then compressor clutch always failed to engage. At that time, air gap between clutch plate and pulley was about 1.2mm. Then we remove the clutch plate and found that the bearing had moved slightly outward. We tapped the bearing lightly so that it sat back to original position and reinstall the clutch plate. The gap was about 0.4mm. AC seems worked properly again now, however the gap gets wider after few hours of operation (now about 0.8mm). I'm afraid that the same problem will soon happen.
My question is:
- by design, what keeps the bearing in its position? I don't see any snap ring or similar that preventing the bearing from moving outward.
- what is possible causes of the bearing moving outward by itself?
- what can I do to fix this problem, other than obvious compressor replacement?
The compressor is scroll type, label says "GM" "QS90". Except electrical connector and pulley, the compressor is visually very similar with QS90 (possibly made by Mitsubishi Heavy Industries) installed in Mitsubishi ASX. Below is screenshot from Mitsubishi service manual, showing where the bearing located. The bearing location is exactly the same with my compressor.