Starter Motor M35G

[rocco]

Hi Gang

While it's still a tad chilly outside I've decided to clean up my starter motor. So far it's all fairly straight forward, the commutator looks in good order so I've only bought new brushes.

I want to withdraw the brushes without snipping the wires, as I've seen done on one youtube video, but the philips screws in the side of the casing are being a bit stubborn. We'll see how stubborn they are once I get the right socket on them and give them some helmet with the rachet or a whack with an impact driver.

My question, for which I've found no answer so far, is whether there is supposed to be some kind of sponge around the inside of the clamp, that covers the brushes? There is definitely some there already although most of it has perished. Seems to me a silly idea but maybe there's a good reason for it that I don't know about?

20230115_193412.jpg (204.64 KiB) Viewed 708 times

Some M35G units don't even have the clamp/cover.

https://www.ebay.co.uk/itm/275636461962 ... %7Ciid%3A3

The best video I've found so far is this guy who's done quite a thorough job.

https://www.youtube.com/watch?v=bRtHnWoImhs

[rocco]

Well then I'm not going to use any sponge and just cover the brushes with the metal wrap.

The armature and bendix is cleaned up and put back together but trying to remove the internals from the case today has been less than successful. First time I used this Philips socket and this, it was only delivered on Wednesday.

Broken_Socket.jpg (118.64 KiB) Viewed 641 times

[svenedin]

When you get the broken metal out try an impact screwdriver such as this. The shock tends to work such screws loose. Worked on my brake drums many times....The screwdriver bits are extremely robust. Also very useful on screws with mashed up slots.

https://www.drapertools.com/product/223 ... -12-piece/

[rocco]

That's a good idea, I'll see about buying one of those impact driver sets of borrowing one.

[philthehill]

As regards the video - I am not impressed with his use of the two small vices to compress the Bendix spring. If one of those vices slipped that spring which has a lot of power when compressed could fly and cause injury. If you are going to show a video of how to do the job I would suggest that the correct tool is used.
Below is the correct starter Bendix spring compression tool for the Minor starter motor. Sykes-Pickavant Pt No: JWP376.

bendix spring tool.jpg (860.87 KiB) Viewed 617 times

The Bendix spring is recessed into both ends of the tool so no chance of the spring flying out and causing injury.
I would recommend that no foam or other material is used under the cover. The cover on its own should be enough to keep out the dirt etc.
The screw that broke your socket looks to be a pole shoe retaining screw which is not meant to be removed for general cleaning etc. If you need to remove the pole shoes you need to use a special screw driver of the type as shown in BMC Minor Wksp Manual, Section N, illustration N6. A normal screw driver or socket screw driver will not loosen or undo the screw. No wonder your Philips screw driver socket broke.
When refitting the pole windings it is best if you use a similar tool to that shown in illustration N7.
I have also left a comment regarding the use of the correct Bendix spring compressor tool on his 'You Tube' comment page.

[rocco]

As it turned out, my starter motor doesn't have the retaining clip that is removed by compressing the spring. It has some kind of threaded wind on/off cap that is a lot easier. Pity I didn't check it before buying a set of 4 mole grips of varying design.

It's difficult to see how I'm going to solder new brushes on without removing the pole shoes so they're going to come out whether they want to or not. I've sized up a tool at work today and they have a decent vice there too so I will give it another go tomorrow.