Fitted brushes now motor sparking

Puzzled This page is about problems encountered after fitting new carbon brushes in a washing machine. If experiencing these issues without having just replaced the brushes though some of this article (and links) may still help.

Motor is sparking

A small amount of sparking is normal. Small sparks may occur until the carbon brushes bed in properly. Little minute sparks are often present but as long as they are very small should not indicate a problem. However, if there is a lot of sparking, particularly if it is flashing or arcing around the commutator then the repair is no good and you should stop using the washing machine before it blows something.

Have brushes been fitted correctly

The first thing to check is have the brushes been fitted correctly? It should be impossible to fit brushes the wrong way these days. The brushes come inside plastic holders. The holders are keyed so that they will only fit in the correct motor and the correct way. However, if for some reason someone has taken brushes out of their holders and manually put new ones in then they can be put the wrong way around.

Also, if someone has fitted the wrong brushes and forced them to fit or removed the keying stubs then you need to fit the proper brushes for the motor in question.

A correctly fitted brush has the curved end of the brush trailing against the commutator (the copper segments). If fitted the wrong way round then only the tip of the brush trails against the commutator instead. This would cause a loud ratchety sound and excessive sparking or lack of power.

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If brushes are fitted correctly, but you still have excessive sparking, especially big flashes, this is caused by poor contact between the brush and the copper segments they run on. This is usually because the commutator (copper segments) is worn or there’s a major fault on the armature. There’s nothing you can do except replace the armature – but as most manufacturer’s no longer supply new armatures – the entire motor.

In most cases now, new armatures can no longer be fitted and a complete new motor would be required. I would be cautious about buying an expensive motor unless you are very confident about the diagnosis and fitting.

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Motor is making a strange noise

When new brushes are fitted there is a period of bedding in needed, during which time (especially on first running) they can make a loud noise as the motor turns. This noise should diminish within a minute or so and diminish more after several washes.

As long as the motor isn’t sparking excessively it should be ok and they should bed in. The noise should be the same when the motor is running as when you turn the drum by hand. It is the noise of new brushes riding over the segments of the commutator on the armature which is always loudest before they bed in.

Motor making loud clicking noise?

If there is a discernible click on each revolution, then one of the copper bars on the commutator that they run on could be loose and slightly raised. In serious cases even missing. This can’t be repaired and a new armature or motor would be required.

To test for this remove the motor from the machine and place a fingertip on the commutator (the copper part with small individual sections). Slowly rotate the armature from the end where the belt fits. See if you can feel if one of more of the copper bars is slightly raised or not. If so the motor needs replacing (if it’s economically viable).

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33 thoughts on “Fitted brushes now motor sparking”

  1. Andy Trigg (Whitegoodshelp)

    I would put it on a normal wash cycle with no laundry in. If they don’t bed in after a few washes and sparking is big the motor may fail. There’s a possibility the main armature is worn.

  2. Hi,

    I replaced the brushes in my Hoover washing machine (Haier motor) – I’m in Australia if it makes any difference.
    The brushes I received from the internet are angled the opposite way – but it is still possible to to fit them so they make full contact because there are pin holes and screw threads that accomodate both ways in the housing. eg. /0/ to \0\
    My question is, will this make any difference? It does seem to be making a lot of noise still after two full cycles – mainly in the clock ways direction which is the fast spin direction. Also, at full speed spin there is sparking.

    Thanks in advance for any help.

  3. Andy Trigg (Whitegoodshelp)

    Hello Charlie. If you had to adjust the way they fit you may have adjusted the angle. Obviously without seeing I can’t judge, but each brush needs to be held at the exact right angle so that the curved part of each brush fits perfectly against the copper commutator. If you have had to adjust where the brushes fit on the motor they may not be running properly. I would imagine that altering the angle that the brush goes in even by a few degrees could have an adverse effect. If the brush isn’t fitted perfectly aligned with the curvature of the commutator then you will get sparks.

    Also make sure you have released the brushes. Most carbon brushes now are held captive inside the brush holder and when fitted they need releasing.

  4. Richard Howram

    I got an F43 error code on my Siemens washer, so after much internetting and struggling to get the motor off, I’ve managed to replace the carbon brushes. The machine is working again now, with the error code gone, but the drum won’t spin up to full speed – it’s turning, but not speeding up to a spin.
    Could this be caused if I’ve managed to put the new brushes in the wrong way? Maybe just one of them?

  5. Andy Trigg (Whitegoodshelp)

    Hello Richard. If the brushes came inside holders it should be impossible to fit them the wrong way around. The holders are usually keyed to fit only one way. If the carbon brushes came separately and had to be placed in the holders then maybe something went wrong, but even so I would think it difficult unless they were the wrong brushes. If a brush is fitted the wrong way around, which is more likely when they don’t fit inside brass holders, then instead of the curved end of the brush running on the commutator only the back edge makes contact. This results in a ratchety clicky sound as each copper segment runs over it. It also results in loss of power and excessive sparking.

    Another possibility of problems is if the brushes didn’t come with new holders and one of the brushes sticks or jams inside the old holder.

  6. Richard Howram

    Hi Andy
    Many thanks for taking the time to respond & offer the benefit of your experience. I took it to bits again and it was immediately apparent after looking over the motor that I’d put one of the brushes in the wrong way. The channels to fit them into were actually angled to the spinning bit, which I hadn’t noticed previously.
    All fixed now & I’m right proud of myself!

  7. Andy Trigg (Whitegoodshelp)

    Thanks for the update Richard. Yes they are keyed so that they should only fit the correct way but obviously not well enough to ensure they can only be fitted one way.

  8. Hi
    I’ve just replaced carbon brushes Nd now when it’s spins fast smoke comes out the back and it smell like burning plastic…


  9. Andy Trigg (Whitegoodshelp)

    Hello Graeme. It sounds very much like the armature is burning out. When this happens the smell produced is quite pungent and persistent. There’s nothing can be done for such a motor. You would need to buy a complete motor and they can be ridiculously expensive. However, having said that if it wasn’t smoking and smelling of burning plastic before you replaced the brushes it could be that you have done something wrong. Is the plastic holder where the carbon brush fits inside somehow touching the commutator (the copper segments)? Or is something else somehow catching? It shouldn’t really be possible but I would take the motor back off and carefully examine it to see if anything is catching as you turn the motor by hand. Also I’m assuming that you have observed the smoke coming out of the back of the motor? If you meant the back of the washing machine then double checked that nothing else like the belt or the motor shaft isn’t catching on something.

  10. Hi just removed carbon brushes from motor but forgot to check positioning any advice on putting new brushes in correctly it’s a Bosch 1400 excell thanks

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