Beogram 4004 (5526): Restoration of DC Platter Motor

After rebuilding the PCBs of the Beogram 4004 (5526) that is currently on my bench it was time to give the squealing DC platter motor a bit of attention. This shows the motor after extracting it from the enclosure:

I took it apart to get to the two Oilite brass bearings:

They are the two small donuts on the black pad up front. I immersed them in motor oil and pulled a vacuum:

Immediately, vigorous bubbling started from both of them. This indicated that the vacuum drew out the air inside the Oilite pores, making room for oil to diffuse back into the bearings. After ~48 hrs the bubbling stopped and I extracted the bearings:

Then it was time to reassemble the motor. For the upper bearing I used my 3D printed tool that allows to flatten the tabs on the retaining ring with sufficient force to get the bearing back into its original location:

This shows the two bearings back in place:

I put the reassembled motor back into the 4004 and installed my BeoloverRPM device for the performance of a 24 hrs RPM stability test:

This is the curve I measured the next day:

This is as good as it gets. This motor is back in business!