Beogram 4002 DC Motor Restoration

 I recently received a Beogram 4002 DC platter motor from Belgium for restoration. This shows the motor as received:

A quick bench test revealed a loudly squealing motor, indicative of dry bearings. I disassembled the motor to get to the bearings:

The bearings are the two small donuts on the black pad upfront. I immersed them in motor oil and pulled a vacuum:

Immediately, strong bubbling started, indicative of air being drawn out of the porous bearing material. This makes room for oil to inter-diffuse into the bearing. After about 3 days the bubbling stopped, and I removed the bearings from the oil:

Then I reassembled the motor and installed it in one of my Beogram 4002s for a 24 hrs RPM stability test with the BeoloverRPM device:

This is the curve I plotted after about 24 hrs of runtime:

This is as good as it gets with the Beogram 4002 DC platter motors. This motor is back in business!