Anyone know about washing machine motors?

[stinkwheel]

My 9 year old panasonic NA127VB4 has packed in. Odd failure. All the pumps, heaters etc work, it's the motor. It sometimes works, sometimes jerks a couple of times as if it's going to start moving then stops and the machine just stops there. You can never get two "starts" where it will move properly in a row off it. It does it both when it's simply trying to rotate the drum or when it's trying to spin so i don't think instability is a factor. There is a slight whining noise from the motor area when it runs but I'm not sure if that's new or just me looking for something.
Being a resourceful chap, I cleaned the motor armature with IPA and changed the brushes (which were nearly down to a nub). Put it all back together agains and... no change.

The drum itself rotates smoothly.

One of the motor bearings is perceptibly looser than the other but there's no actual detectable play. I've tested the resistance of the windings, field coils and movement sensor (I think it's a hall effect?) against the manual. All appear to be within normal limits.

I stripped the motor and noticed these dings in the rotor. They are symmetrically diagonally opposite (if there's a ding on the front on one side, there is a similar size ding on the back and opposite side). I can't see any damage in the field coils or housing that explains this but surely it's significant? Must have taken a fair old whack.

The whole area is enclosed in the field coils and motor housing so it's not like something can just drop in there.
Suggestions? (Yeah, yeah, I know, buy a new one but I've gone this far now)

https://lh3.googleusercontent.com/pw/ACtC-3dcgPrmLsZ6_aFewaZ_RisLTKBM3IEEJ2uRpVVqLc44Ly2_Y5o8xljTAd2t7p8vSKcu_83eQIm_qL7vET6IxTf5lv3lHOAWVFo3eQ0lhWCRr9LEHGoN4dkF9JqsUoxvPkMf8F5RFi6QvTL22H80ebwX=w1529-h860-no

https://lh3.googleusercontent.com/pw/ACtC-3f_2jPz9PIYNSfY-UMX3VjpAeh_oj0LMuAW6rsoeJZR4H8vXG8KofrclpD9XEgK5G5QMOtxAlzhv0k5rDP10ifHyQ2o1tZZEqKUSATHImhrK9_9XcigIedmDuTt3hZhu6p46kEsVEh7-if2sy7aTqUE=w1529-h860-no

https://lh3.googleusercontent.com/pw/ACtC-3dNc4n13Xuiwn1PMSSBmvzNxnw5O6V3FwwO-EHArBcPljDoh_gS4kR9tkQbhZDM7z3hPuaxBrUV0Y4dKsy9tQMQ8KOlMa6uwjavG8MUqjhaYd2fguGKyNOpe3t4Kz5jcUlKQvO2hQC8a4p3NikvWmO6=w1529-h860-no

https://lh3.googleusercontent.com/pw/ACtC-3dOHuuqHaYkXb0mvcvp2xmqV3jiw2M857sWUV1x_lHoHWLeZskTgnHydWYzCvFYp2kwpDGslQzBL9K3n_IeY-amSpwqPsEE6qqWyXGCMWRCmaOl6qE-pnrkMKdjsSHdIkWVNAoIMQteMJAKHrJvWUS0=w1529-h860-no
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Nobby the Bastard]

Are you sure its the motor and not the controlling electronics?
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Islander]

Are they actually dings or could they be material removed for balancing?

[stinkwheel]

At this point I'm not sure about anything. I'd sure like to know where those dings came from. Interesting how they are in the centre of and inline with the iron cores and not inline with the spindle.

I should add I put it into a diagnostic cycle too which is supposed to just spin the drum with no balancing etc and it did the same thing btu did not return any errors.

It's pretty much looking like new washer time. A new motor is £70 which is a third of the way to a new machine with no garauntee it'll fix it.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[stinkwheel]

[virus]

Those dents look like balancing to me too, they are too even and in a logical pattern opposite each other to be random damage, especially with no damage to the magnets.
____________________
own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[stinkwheel]

Just for the shit of it I've pulled the bearings (more to see if I could). One of them has a noticeable notch which you couldn't feel with it on the shaft. Not much but it's there. I wonder if this is sending an oddball "wobble" signal to the hall effect sensor and making it cut out?
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[sickpup]

I would be measuring the voltage at the motor while trying to run. If it has a constant voltage when it's trying to run it suggests its the motor OR the motor sensor/tacho coil which tells the machine the speed the motor is rotating.

If the motor is 12v I would test it off a car battery, if 230V off the mains as this would eliminate or put the blame squarely on the motor.

If the motor is ok I'd look at the tacho coil. Easy way to check it s a multimeter on DC volts, connect to the tacho coil which has 2 wires and rotate the drum, should give a few volts. Tacho coil will have 2 wires the same colour probably thinner than the others

Lots of youtube vids for checking the motor and tacho coil.

Thats about the extent of my knowledge which is probably the same as yours.

This explains a bit better than do.

[stinkwheel]

Here's the sensor/coil/whatever.
https://lh3.googleusercontent.com/pw/ACtC-3ecPPnv_M3kKqMy75JGpaQQjvotOUDIzGK4DhNICaBW7cXoWk_APC0PQ-C8CNLW13FISUkoPjoA709G8E_KeItMl5cTeGmCA2v9tvD0_XCcbZ3XkmFDB70lhtCNeZp330HIRJ8JzfSifV7gbo1h9P4D=w1529-h860-no

It must be quite sophisticated because it's the only sensor to do with the motor and drum. This is the only way it has of detecting an imbalance and setting the motor speed for a spin. It can tell if Mrs stinkwheel has tried to sneak in an extra bedsheet.

I just pulled the bearings to see how hard it would be (easy with a 3-leg puller). One of them does have a perceptible notch on it that you couldn't feel with it in-situ. if that sensor is very delicate, maybe this is tripping it at low speeds. Worth a punt for the price of a couple of 6202s against the price of a new washing machine.

I want to be able to fix this. I can fix a V4 Japanese motorcycle, it's a washing machine, it is a lot less complex!
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Islander]

I don't know if this is useful to you or not - it's a service manual (downloadable too). I've linked to the motor section and there are various wiring diagrams in the subsequent pages as well.

https://www.manualslib.com/manual/1049085/Panasonic-Na-127vb4.html?page=39#manual

[sickpup]

I would guess it works pretty much the same as a pick up coil

[WD Forte]

I reckon the 'Dings' are from when it was balanced after winding
and material removed cos adding weight not a practical option.
If the windings, commutator and brushes are all good I'd suspect the
rotation sensor or control circuit.

Could be dry joint on the control PCB for instance.
I'd check the connectors for crimping & soldering and around the main power
Mosfets/SCRS/Triacs or whatever they use.( probly triacs)
See if any caps have dried out/gone bulgy as well
Any slight play in the bearings wouldn't have much effect IMO.

I had a WM motor plunge the house into darkness one night when a screw fell out of the
brush holder and shorted the thing out
I doubt its that on yours though
____________________
bikers smell of wee

[WD Forte]

Just for fun check the resistance of the tacho wires as well.

Most older ones are just basic AC out pulsers like you'd find on manys a bike.
Typical resistance would be in the 60-70 ohm region,
____________________
bikers smell of wee

[stinkwheel]

[A100man]

[Islander]

[stinkwheel]

Ok. Had a poke at the electronics. There's no real way of getting at them with them powered up, you have to unplug several multipin connectors to get the PCB out of its housing.

I did notice a scorchy bit (technical term). Circled here:
https://lh3.googleusercontent.com/pw/ACtC-3dMi8Rhd8WU-xSrcVGwFFRMYcoKM5IslZF9z0wtILLkifdoI4ZxlR_sWyKpnT9KE6YVJtwkFGU4w7XO_gSUeAQfHUy9ks_DFpqtGmR5b4BufmMj82CFBthkZc7gWfwKdK3C9doUWL4ZivmeO8CjNiFE=w1529-h860-no

And on the other side:
https://lh3.googleusercontent.com/pw/ACtC-3ff0XDOLW2KQirfq55wnCItCu_4FYzKsdRV6MUgMSlTMr2WwZBd7b5Tbf0CLJT3zdCXyb54vbrpsH6nXavDTXhrz0sPWiJll5YemRRMwGki7jKByxgUwf9ar_gOdzm3Gq-fNuuo-tskOT9Ve010EtGS=w1529-h860-no

Close up, you can see there is a diode and a 10uf capacitor in that areat:
https://lh3.googleusercontent.com/pw/ACtC-3e11HlqI4rufE8djE76IhqQsYTTqytA-U4WEF6VRUuYeQNKADaeoVoAwau9DW5xKkLmDiUYzBI5bEa9HWK1uuMqZ_dIKnm-2s_Y6h13wX2P1-rfm_XP3AEomqGFS9tmKLM3L2yUvlGd6nrw2SRmLmf_=w1529-h860-no

Looking at the other side, also has one edge of an IC. I've googled the chip number with no joy. The solder of the capacitor looks a little burny?
https://lh3.googleusercontent.com/pw/ACtC-3c0omBJfYXai-TcCtstoIYZGLH4Pre3h1JFFkbYD5ugtKn7c9TqX8LcIamFWSUngfDxou1ovduR5zXimXtPKRglUB7ZcaDV91AmgGJRbU5FfCNN7L4a6S3kjpzrOawzZcM64fpLSQMr7JAwVUy9w_w2=w484-h860-no

However extreme close-up of the diode looks like it's gone off bang? (Mmm, new camera macro function working well!).
https://lh3.googleusercontent.com/pw/ACtC-3ckNQ5-QJweQzIfKIEGjzcZBPuvJPDJUBULDHSUA9CCQKfBFvvtW18z76VeUPnN5naLOrWsvsoALG1wyYGmSGCJNlBp0Lmxe3s3uZjCuuQFy_h8hhzgL_QoxT-7lewaN1b-tBIsxn3newr1AZxWE3xd=w1529-h860-no

I'm out of my depth now. Like my feet can touch the bottom but my nose is underwater so I'm not drowning but am distinctly uncomfortable. I suppose what I need to do is test that diode and capacitor? Will an ordinary multimeter be up to the task?

My soldering skills are probably JUST up to replacing that diode if I can get a good enough look to see which one it is.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[doggone]

The capacitor at least might be very standard and available for under £5, at this point you might as well desolder and pull them out for better look if need be.
If soldering is not a strong point cut leaving the legs in place to tack onto them, or leave the failed unit in place it won't hurt if you can put new alongside to save risk of damage

[Robby]

I'm also way out of my depth here, but thinking about the potential cause. It would be a fairly sweet planned obsolescence trick if when the brushes wear down to almost nothing and require a big current draw to operate, that overloads something on the circuit board and pops a component.

As you have found, changing the brushes is well within the competence of a general purpose tinkerer. Understanding and fixing a white goods circuit board is something else. As we all know, replacement boards are expensive enough to only be worth doing on something new enough to be in warranty.

Assuming you are going to fix it, worth checking the bearings on the drum as well while you have it apart. I'm always quite impressed by how well they last considering the abuse they take and the environment they work in.

[Skudd]

My last washing machine it was the electronics, Got a new card for it, but thought with it being a nice day I would put it by the front door in the walled garden and give the kitchen floor a good deep clean. It only took me about an hour, went to bring the washing machine back in and the bloody tinker rag and bone man had taken it. I wouldn't mind but I was only about 10 yards away from it and I never heard the little thieving Gypsy Tinkers.
Suffice to say I had to get a new one.
____________________
Famous last words of Humpty Dumpty. " Stop pushing me "
Petty Anarchists look at "1984".............. The Visionary looks at "Animal Farm".

[Islander]

The diode looks like a standard 1N400x type, It's probably acting as a rectifier and the capacitor as a decoupling (smoothing) device. That could be your problem right there if it's providing DC to something on the board. If so it'd be a cheap fix.

[stinkwheel]

Hmm. There is a diode setting on one of my multimeters. I tested that one and a similar one next to it and they both show infinity one way, and a similar reading the other, which is pretty much what I'd expect. So probably not the diode.

Off to find out how you test a capacitor?
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Islander]

[steve the grease]

As someone who , in the mists of time, was a Milling machine setter/ operator, I can confirm that the 'dings ' are most definitely the marks from a milling machine cutter in the process of balancing the armature.
____________________
All the above is my personal opinion, you can see my lips move, but I'm talking out of my arse.
I've been riding, and fixing , bikes for 50 years, in that time the more I learn, the less I am absolutely sure of.....

[stinkwheel]

Hmm. Discharged capacitor starts with low resistance which steadily increases but doesn't reach infinity. I think that's normal since it's not been removed from the board so you wouldn't expect it to become fully saturated. Wonder if I should just replace it anyway.

I'd have thought if a critical IC had failed, which is the only other thing in the vicinity of that scorch mark, it would either work or not.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.