[johnboy183]

Sorry for the delay in updating this post but have been away for a couple of weeks and have only just installed the Magnetron (Im sure that was the name of a death ray in Captain Scarlet and the Mysterons way back )
Anyway it would appear that the burnt out Mag was indeed the problem as machine now fully working again.
Kaibart – I have indeed strongly advised the “customer” (my wife!) of what you have said which as you might imagine went down very well as these pieces of advice do!!
Thanks again everyone for your invaluable advice and help as always.
kind regards
John

[johnboy183]

Thanks both.
managed to order a brand new identical and genuine mag from eBay for £47 delivered – far cheaper than from bosch!
I can’t see any obvious burnt or blown caps or components on the inverter board so shall see if the mag replacement fixes the problem and if not I will delve deeper. ( the oven is some 10 years old and the microwave has been used a lot so hopefully just a worn out magnetron). I will report back later and hope the outcome also helps others. John

[johnboy183]

Hi Dave,
Tested the magnetron in situ and it seemed to test out as ok using the various Multimeter tests. However for completeness I decided to remove it for a full inspection and found the damage shown in the attached photos! Hopefully the Magnetron replacement will effect a cure unless there are other unforeseen issues. Would welcome your views?
john

[johnboy183]

Hi Dave,
Thanks for the very quick reply.
Are the caps in the “conventional circuit” those on the Invertor board? (see photo) Are any of these 5000volt capability of do invertor models not have these very high voltage caps?
Exploring what you asked me to try do you mean to have the outer case off and activate the microwave while looking through the holes in the mag to look for a glow? (see other photo) – and is this safe?
John

[johnboy183]

On my motor label it has
MCA 61/64 – 148/SM7
Anyone explain what these figures relate to so I can understand their importance on sourcing a replacement?
Thanks
John

[johnboy183]

Ok Dave thanks. Time to just sit and think I guess.

[johnboy183]

Well the repeat “bodge” went very well using the half brushes from before and the original longer brass holders. I first of all just ran the motor on the floor connected to the loom and it ran well with only tiny intermittent sparking as the brushes moulded to the commie. I also ran it like this using the programmes to execute a spin. The motor ran progressively faster though all its stages reaching 17,000 rpm which would equate to about 1700 at the drum (don’t forget it had no load as it was unconnected). At that speed there was a fair amount of commie sparking but looking at it closely it was all at the edges of the brushes – still bedding in I think – as there was no smoke and the motor casing remained only warm. (Dave – I did video this as you suggested but it was very shaky with a lot of wasted video – will try and edit to shorten and see if I can post it).
I then installed the motor, loaded it with washing and ran a full 2 hour programme while observing for any sparking at the motor. Again at wash speed the sparking was almost non existent and at full spin the drum reached 1300rpm which would be normal as the load was quite unbalanced I suspect. At that speed again there was more sparking at commie but no more than earlier observed and no smoke or overheating.
When the wash finished I ran a spin mode with the drum empty and the drum reached just on 1350rpm.
I then removed the motor and checked the commie and brushes and they showed no overheating or heavy blackening of the commie.
Today I have ordered a set of Ceset brushes and holders and will repeat the above when they arrive.
I contacted the seller of the Indeset motor and asked re the pulley diameter and as you guessed it was 19mm (and mine is 22mm).
The guy selling the Bosch motor with the missing 0 in its description I contacted again but am getting no helpful reply and he still seems reluctant to discuss the model number so that I could go ahead (and he is a big established parts seller!).
A possible solution would be to buy the Indeset motor and swop the pulley from mine to it (as I suspected they are only heat shrunk onto the shaft so removal should be straightforward in my workshop).
Again any comments or thoughts on the above would be very welcome.

[johnboy183]

Well spotted Dave! When this motor stopped running many months ago one brush was worn to the point of not reaching the commie – hence why it stopped. While I sourced replacement brushes (and in order to keep “my boss” able to do the washing) I found two old brushes from some other motor that were the right width and thickness (but not able to substitute as wires were different and they were just too short). So I ground the ends of the existing brushes flat and removed the wires of these extra brush ends and ground their ends to the correct angle and pushed them in to the holder as a sandwich to try. It worked very successfully (no sparking etc) for a couple of weeks until the new brushes arrived. In fact it was so successful I might (in hindsight) have been better to leave them in rather than having put in what have turned out to be very poor replacements.
I have found these two brush ends again last night so today am going to try the bodge again and see how that goes while looking for the longer term solution.

[johnboy183]

Just a follow up to add. Looking again at the item the case structure is slightly different to mine so not sure it is a CSET motor and I had asked him to let me know what the printed details on the top of the case are and he has not done so therefore unable to check its spec.

[johnboy183]

Thanks Dave,
I totally agree which is why I messaged the seller in the first place and later told him about WKD2835 not being valid. He said he would look into it and get back to me but has not done that so far.
I was going to message him again today but wonder if the best thing would be to simply make an offer on it and take the risk it would be a suitable replacement. At worst it would still provide me with authentic replacement brushes and holders to go on my motor to help it keep running in the interim.
What do you think?
John

[johnboy183]

Thanks Dave. That ebay item is one I contacted the seller about but he says it is not for a WKD28350gb/03 it is for a WKD2835gb/03 but that machine doesn’t exist according to Bosch!!:(
I am also looking at this one as a possibility: http://www.ebay.co.uk/itm/235301013219
What do you think?
John

[johnboy183]

Thanks again for the comments. I had thought about pulley size as obviously the drum pulley to motor pulley size differences would magnify or deplete any drum rpm by a small change in motor pulley size and of course pulleys can be changed though not easily. Beyond that I fail to see why other motors of equivalent spec and the same attachment points couldn’t be adapted to work if I cant get a second hand motor that is identical part number and certainly nopt one at Bosch’s extortionate prices!!.
I assume your request to run a 360 degree video of the commie was to see if there were any obvious individual segment differences? I will do that if I can but I can assure you every segment now is as the appearance on the photo displays. I have even rotated the motor with a DTI on the commie and it shows less than 2 thou difference on the complete rotation with no raised, lowered, loose or shorted segments showing. I am going to run some further tests tomorrow and will report back on them.
John

[johnboy183]

Any thoughts on what I said about differences between motors – as I am struggling to find the exact part number?

[johnboy183]

I am looking at the uploaded images on the forum now so can only assume you are not seeing them if using a mobile to view. I would value your take on the photos as that is why I spent a lot of time taking and editing them. Will try attaching again.
As a supplementary question I am finding getting a replacement motor second hand for this particular washer almost impossible especially as responders on here tell me it must be fully identical (even though many look physically identical). Can I ask why being totally identical is the case as if it is the same main spec from the label plate and there seems to be no additional PCBs in the motor itself with only a rpm sensor (rev counter) on the motor shaft I must be missing something?
kind regards
John

[johnboy183]

Thank you for the comments and suggestions they are much appreciated.
You are right that the motor is a CES one (photos are included). The brushes were a propriety make but cant find the paperwork anywhere. The brushes on this motor are the type fixed in the brass sleeve and cant be removed and so cant be installed wrong way round. HOWEVER now re-looking at these I have no idea where my head was at when I accepted these as suitable replacements!
As you will see from the accompanying photos when compared to the originals (which I still have and show in the photos) the brass sleeve sits far higher inside the plastic holder and is shorter than the originals brass sleeve so exposing more of the plastic holder to the heat and any sparking. It also offers far less support to the brush end nearest the commutator! The bad news doesn’t end there as I now find the “new” brushes are only 12mm wide and the originals 13.5mm. I am sure much of this is probably why the commutator and surrounding area are coated in sooty melted plastic.
What I did yesterday was to roughly clean the commie and brushes, holders etc. and run the motor on the floor at the base of the washing machine (loom was just long enough to reach). I was surprised to find the motor ran fairly well with almost no sparking on the commie. When it ran up to high speed there was some sparking but no “magic” smoke. I then installed the motor and ran two full 2hour washing sessions with a full load in each run.
Both runs completed successfully but with a fair amount of sparking when the washer was at full speed spinning – but again no smoke. The tub would not reach 1400rpm ( measured with a rev counter) but I think this could be due to the narrower brushes and the generally poor state of cleanliness of the commie.
So today I cleaned and resurfaced the commie properly (see photo) and took and edited the photos I have attached.
Hopefully if I can get some correct brushes and replacement plastic brush holders there may still be a chance of salvation yet! I would welcome your views or thoughts on this update.

John ​

[Author]

Posts