Electra WD1100 washer/dryer problem

[franglais]

While the machine fills with water at the beginning of a cycle, the drum is meant to turn the clothes over intermittently. The problem is that the motor starts to turn the drum, but manages only a quarter turn before giving up.
Opening the back, I am able to help the drum pulley around manually when the motor switches in, so it feels like the motor cannot muster sufficient power to do the job alone.
However, the motor is fine when it comes to the spin cycle and everything else is fine.
Any suggestions what might be the problem?

 

[IanDB]

It could be the brushes. A motor exhibits loss of power when these wear out.

 

[franglais]

Thanks for your reply.
Looking at the motor, I think it may be a brushless type. I can see 7 wires entering the body of the motor, presumably to field windings. Then there are two wires connecting to a component housed in a shallow metal cylinder bolted to the rear of the motor over the motor spindle. On removal I can see a multipole ring-shaped magnet on the spindle. I think this must be a device to monitor the rotation of the motor.
What do you reckon?

 

[breezer]

sounds like you are refering to a tacho, yes it does monitor speed.
are you sure it doesnt have brushes

 

[franglais]

I'm pretty sure there are no brushes. And I can't see any signs of any windings having burnt out. Any idea what else might be causing the problem?