Bosch WFO2866gb not turning

[TH3 M0L3]

My girlfriends Bosch WFO2866GB started making strange noises a few days ago, and has now stopped working. I offered to take a look, so tried it on the spin cycle. The drain pump kicked in and the timer showed 12 minutes. After a few attempts to start the motor (i could hear the relays clicking in and out) the timer went to one minute and stopped without the drum spinning.
I took the motor out to examine the brushes and found them to be very worn down. They were probably about 1.5cm from the base at the spring to the sharp end. I searched online and the pictures of the new brushes show that they should be a lot longer.
What are my chances of this being the fault and not the pcb or speed controller?

While the motor was out, I took the opportunity to open it to inspect the stator, this appeared to be ok, although covered in the carbon dust from the brushes.

Is there anything else I could check if the brushes dont work?

[Penguin45]

Re: Bosch WFO2866gb not turning

Test meter is your friend. Meter across the motor terminals and ensure that the circuit shows 5-10 ohms. If you already have the brushes out of the motor, check that the running surfaces of both are nice and shiny. If one looks dull, they’re finished and need replacing.

Penguin45.

[TH3 M0L3]

Re: Bosch WFO2866gb not turning

Penguin45 wrote:Meter across the motor terminals and ensure that the circuit shows 5-10 ohms

is this the same for all terminals as there are, as you probably know, a few.
I am used to working on induction motors as I am a air-con/chiller engineer, but don’t come across these motors at all so not familiar with them?

Penguin45 wrote:check that the running surfaces of both are nice and shiny. If one looks dull, they’re finished and need replacing.

One of the brushes has a silvery surface, the other not. You can see the wire in the end of the latter brush, so I’m guessing this is my problem

[TH3 M0L3]

Re: Bosch WFO2866gb not turning

Well, the resistance of the windings was somewhat confusing as there are multiple terminals. The most I got was 1.5 ohms.

Anyway, regardless of that, I replaces the brushes which did the trick.
The machine even runs quieter now because I cleaned the motor out too.

Thanks for the info.

[TH3 M0L3]

Re: Bosch WFO2866gb not turning

Ps I have earned major brownie points for doing this
😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛 😛

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