Repairing a Siemens Schuckertwerke AC Motor

Motor overview

Nameplate

Disassembly

Te screws of the bearing covers were completely sheared off, probably from vibrational damage.

New bearings

Replaced the old bearings with new SKF 6200-2RSH ones.

New bearings

Odd screws

The screws holding the bearing cover were of an odd dimension, either imperial or something like M3.5.

I decided to rethread the inner plate to M4, so I can use standard screws. To do this I used a 3.5mm reamer to clean up the hole and re-threaded it to M4.

Rethreading

Cleaning up some mess

My hand press wasn’t high enough to fit the stator under, so I had to abuse my drill press to press the bearings and small steel rings in. Unfortunately this left some marks on the steel ring, so I cleaned this up (taking off ~10um) on the lathe.

Lathing

Reassembly

Connection box

The connection box is interesting in that it doesn’t provide a seal or gasket but instead relies on milled surfaces to achieve water tightness. I cleaned these up with a scouring pad.

Connection box

Aftermath

Motor after repair

Contents