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Hi, just registered and this is my first post, hoping someone might be able to help.
The other day I noticed the machine wasn’t spinning the drum although the counter was running down and “finishing” the programme.
Had a look at the back, hoping snapped belt was the culprit, but no such luck. Noticed that when I gave the big wheel at the back of the drum that the belt goes around a little bit of a “nudge” it would start spinning. However, after a few minutes of careful poking around (doing nothing other than trying to see if it will spin at all on its own, or only when I give it a push) there was a bang, a fuse tripped and a little smoke and a burning smell appeared from the motor.
After some googling, I took the motor out and found the brushes were totally worn down, with about 5-6mm left of each and the copper wire visible in the centre of the ends that press against the commutator. I also noticed where a short happened, the very worn old brush must’ve somehow caused it, but I could see no visible lasting damage, just a bit of blackening and a tiny blob of melted metal. I cleaned everything as best as I could, and fitted new brushes which I ordered, paying attention to install them correctly because of the way they’re angled. I installed the motor back in, connected everything back up, but I wasn’t in luck. This time, the machine gave no sign of life whatsoever after being plugged into mains. The display doesn’t come on at all, and it’s appears completely dead. It’s as if there’s an internal fuse somewhere which may have tripped.
I googled everything a bit more, took the motor back out, opened it up again, and tested the thermal fuse and I think it’s ok (my multimeter beeps when I touch the ends of it with the black and red electrode)? Also, there’s no continuity between any of the 6 connectors in the plug and the body (earth) of the motor. The motor looks fine to me (but I could of course be wrong, as I’m only an amateur).
Forgot to say I also tested the fuse in the plug, which was fine, and verified that 240v shows on the live and neutral connectors plugged into a component (don’t know what that component is though) where the main cable goes into the machine at the back.
Could anyone suggest what I could check next, or if there’s some sort of a main internal fuse?
Very grateful in advance,
Vlad.
i would say you have melted a track on the timer due to playing with the pulley
take out the timer and inspect the tracks for damage
Dave
Hi Dave,
Many thanks for such a prompt reply.
I’m sorry, as I’m not an expert on this, could you please explain a little further. Is the timer a component in the motor? Where are these tracks I should be looking at?
Very grateful for your help.
Vlad.
the fact its dead means it cant be a motor fault athough it was at first
the tracks are copper conducters on the printed circuit board of the timer
its in the front panel
Dave
But if the tracks have blown on the pcboard a component part on that pcb might be damaged too and you still have the motor problem i.e. a new motor ( armature failure / blown stator overload). Becareful you do not get caught in an expensive repair loop. Check the board first as recommended then see what happens. Look up on Bosch`s own parts website the cost of the parts that may well be required and if so you will find that the pcb is £222.18 part number 00448305 and the motor is £193.80 part number 00144797………sorry to say it is a free bucket of freezing cold water to bathe those burnt paws with every purchase!!! If so do not go there is my advice.
I’ve only just had a chance to have a proper look at this. It’s not looking great, several tracks look blown, see attached pictures. Also some blackening around some tracks although those tracks themselves don’t look blown.
Is it even worth looking further at this? Can the tracks be repaired, by soldering a piece of wire to bridge the blown part?
I couldn’t attach pictures as they’re over the allowed file size, please have a look here:
https://photos.app.goo.gl/sNtbe9ri7KEYfFSz9
Many thanks!
well its worth a try
you can repair the tracks with 15a or 30a fuse wire and a soldering iron
what i think has happened is the motor had a surge when you turned it on which blew the tracks
when you fix them put a 5 amp fuse in the plug. that way if it goes bang it wont be a big one. the only reason for the 13a fuse is to accommodate the heater so if you select rinse or spin it wont energise
Dave
I took the PCB out (so fiddly!) and this is what one component at the back looks like. It’s covered in soot. Does it look like it’s burned out?
Grrr, again can’t upload pictures, please see the original link to photos, I added it there.
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