Welcome to Beoworld !

The Beocenter 3500 is a wonderful machine and definitely worth fixing.

When B&O tells you that it cannot be fixed, they are merely telling you that
- They can no longer supply the motor
- They have no tech guys at their authorized repairshops capable of taking the motor apart, clean and lubricate.

It's the old lubricants that has dried in the sintered bronze bearings. It will have to be removed and fresh oil
pressed in. Not the easiest task but it can be done.

Martin

thank you so much what type of lube do you recomend?  

That would be mineral SAE30 since it contains the additives needed but do a google search on
pre-oiled sintered bronze bearings and how to re-oil them.
It's not just a matter of adding a couple of drops, the process involves boiling and the best
results are achieved if you have a vacuum chamber but there are other ways.
The bearings should be re-oiled before becoming worn. When the oil dries and no longer
flows out from the pores of the material, the bearing and motor spindle will run metal against
metal and that will wear the bearings quickly.

Martin

I have a beocenter 3500 too, but my engine spins the exact speed. Does that mean I don't have to relubricate those bearings?

Yes but I wouldn't expect every Beocenter 3500 to run forever without fresh oil.
The problem with the bearings is that when the oil has hardened (or been used up),
the bearings and spindle will begin to run metal against metal. That will cause a drastic increase in friction
and the bearings will be worn very quickly (a few hours playing time).
The delicate poreus surface of the bearings will start to smear out and the bearings (or bushings as they
really are) will have to be replaced rather than re-oiled.
This is the cause for many motors showing good repair signs at first try but the next day
they are running slow again. Bearings like these often cannot be saved.
The spindle will normally run on a very thin film of oil inside the bearing, never in metallic contact
and the extremely low friction this provides is essential for maintaining correct speed on these
one-phase AC motors, who theoretically have no serious torque (but will theoretically never wear out if
oiled correctly).
Along with many other projects, I am currently working on having these bushings re-produced,
they are non-standard sizes so cannot be found anywhere.
If the motor is still working fine, the bearings will not have started to wear yet and that would be
the ideal time for re-lubricating.

Martin

I'm glad of what I hear from you on the one side, but not so happy on the other side. I think it's a masive undertaking to relubricate them, especially as I am not very fond of screwing these machines open and do a bit of 'trial and error'. I don't even know how the machine looks from the inside (sorry guys, but I've only found this one on the attic a month a go or so). So if someone has got some instructions and/or photo's on how to do this it would help a lot.

The machine was serviced about 15 years ago and didn't run since then. It was kept in a dry and cool room so It didn't suffer a lot of wear. 

Noone can help me?

Lennaert,

I just had a look around and the service manual is available on site if you upgrade your membership to the Silver/Gold level.

I do have the service manual at the moment. It just shows circuitboards and such and I'm totally non-technic in the case of circuitboards.