Maho Mh600E Indramat Drive

Recently purchased a Maho MH600E. I kept getting Error Y07 when trying to start machine using start and clear and all three axis would move until they hit end stops.

I disconnected the cable from the Y motor and then the X and Z axis stopped moving when trying to start ( is a bit of drifting ).
I removed the motor and took brushes out - the rotor looks black inside and brushes have a lot of grease etc.. so figure this must be causing the problems.
Does anyone know how to disassemble so I can clean the rotor.
I removed the cap that houses the magnets ( not sure if this is the tacho or brake ).
Cant see how to remove this to get to shaft. Maybe a bearing puller ?
There are 4 threaded holes that could be used to push it out - tried this but scared I brake the bolts( M4 i think ) .

Thanks,
Paul

Attached Thumbnails