Problems after fitting carbon brushes

Puzzled If you fitted new carbon brushes in a washing machine motor and now the motor doesn’t run there are some things you need to check.

Fitted new brushes but the motor doesn’t run

The first thing to think about is, did the motor run before you replaced the brushes? Maybe they were replaced because they were sparking, or the motor was struggling, or simply during maintenance. If it did, run but now it doesn’t run at all then it’s clearly something you’ve done whilst fitting them.


But if the motor wasn’t running before you fitted brushes and it still isn’t running with new ones fitted then there are two possibilities. First, you have done something wrong, but second, you may have fitted them perfectly okay but misdiagnosed the fault. In other words one possibility for the motor not running is that the fault was never to do with carbon brushes at all. The only way you can work this one out is to carefully check your work and if satisfied it is okay then there must be a different fault (possible causes of motor not running).

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Check the motor plug

Make sure motor plug is connected to the motor, and connected properly. If it is, unplug it and check the pins in both the motor connector block and the motor plug to make sure none of them have pushed inwards when they were pushed together. Sometimes if the pins don’t align properly, when they get pushed together one of the pins can get pushed out of its seating.


Gently press down on each pin in the motor block to see if any push down under slight pressure – only gently though, we don’t want to create a fault that wasn’t there before.

Check the wires on the carbon brushes

Check that the small wires on both carbon brush holders are connected properly. There should be an electrical connection to both brushes.

Ideally, check continuity across the carbon brushes with a continuity test meter to make sure they are contacting the commutator properly. Test by measuring with a meter across the two appropriate pins in the motor plug block on the motor so that you are testing down one pin, to a carbon brush, then across the commutator over to the other brush and then up to the other pin.

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Were the brushes fitted the right way round?

Check that you fitted the brushes in the correct way around. Modern carbon brushes are usually designed so that they will only fit one way. However, many replacement carbon brushes non-genuine copies. Sometimes they are not exact and need to be modified before fitting, or you may have once for a slightly different motor.

Did you have to file any lugs off or make any adjustments to get them to fit? If so they may not be fitted properly. Did you replace the entire carbon brush and the holders? If you actually fitted just the brush inside existing holders this is not ideal at all. Make sure they are fitted the correct way around…

Take the brushes back out and make sure one or both haven’t stuck inside their holders. If the motor did run for several washes but then packed in check to see if both have been making good contact. If one is charred it may have been stuck in the holder. This can especially happen on older Hotpoint or Creda brushes if you didn’t release the small brass lug properly. The brush should be able to be pressed all the way in and spring straight back out when you let go.


Were the old brushes actually faulty?

If you are confident that you have fitted them correctly and nothing has gone wrong during the repair Carbon brushes article contains useful diagnostic advice for all carbon brushes, with pictures)

Do further research

Research the Washerhelp forum under the Hotpoint & Creda section. Try searching for “carbon brushes”. You may find a solution there. Try searching also for TOC. The TOC (thermal overload cut-out) in the motor may have blown. You will need a continuity test meter to test for this.

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2 thoughts on “Problems after fitting carbon brushes”

  1. We have an Indesit washing machine XWD71452. This week it developed a fault with the drum. It seems to be trying to turn but is unable to do so, or occasionally it does turn but seems unable to reach the required speed for a spin or to maintain a steady tumble. We checked the brushes and although they don’t appear to be worn we replaced them anyway. This has not corrected the problem. Do you have any suggestions as to the possible cause of this fault. The machine is filling and pumping out as normal.

  2. Andy Trigg (Whitegoodshelp)

    Hello Malcolm. Aye that’s why I wrote my article on carbon brushes diagnostics. So many people waste time and money on a hope :) Unlucky though as carbon brushes are the most common cause of motor problems.

    If the motor is struggling to turn and it’s not the belt slipping or the brushes, we would next look for dodgy connections on the motor block and/or motor plug, broken wires in the motor harness going from motor plug down to the pcb or faults on the main pcb. I would not recommend trying changing the pcb though.

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