Yet another Starting Problem

[geoberni]

You're getting incorrect info from the ebay listing.
That is a Solenoid from a M35J PE, ie the pre engaged version. The Minor used the inertia M35J.

M35J models have a Flat Commutator with Triangular brushes pressing on the end.
Like this:

M35J.JPG (58.44 KiB) Viewed 6569 times

M35G are a more conventional commutator with brushes pressing onto the side, just as the Dynamo does.

Hence why ESM sell the 2 types: https://www.morrisminorspares.com/searc ... otor-brush

Lucas made many starter and dynamos models, earlier designs had the inspection window, latter ones didn't.
So as a rule of thumb, the one with inspection window is oldest.

I don't know about the 'Isuzu and even some old Honda starters' being compatible.
Just because they look the same, some starters will turn the other direction; all done by the way the stator and armature windings are electrically connected.

[svenedin]

There are lots of M35G and M35J starter motors around as they were used in many different cars over a long period. If you cannot repair the ones that you have it would surely be easiest to exchange one of them for a rebuilt unit? A properly rebuilt starter motor should be reliable for many years.

Stephen

[rocco]

Thanks Berni, Stephen. I think after considering the cost of buying new bushes, brushes and some kind of spring compressor to get the bügger open, I'm better off just buying a new one. I've found an LRS102 (25083) model with a 10-tooth bendix which I have just made an offer on.

[oliver90owner]

I note in a previous post that you ‘lubricated’ the bendix.

The bendix should operate dry - anything oily can cause dust to adhere and eventually impair its operation.

[Mervin]

I have used graphite powder, to "lubricate" with good effect.

[rocco]

I note in a previous post that you ‘lubricated’ the bendix.

The bendix should operate dry - anything oily can cause dust to adhere and eventually impair its operation.

It was dry and binding before I squirted it and thereafter it moved freely. I blasted it in brake cleaner last night and was thinking about giving it some WD40 silicone spray which seems to repel dirt a little bit.

[svenedin]

Get a Bendix spring compressor or borrow one (or make one, there's a diagram to make one in the book in the photo). Take the Bendix apart. Clean all dirt and rust off, degrease it all with Petrol, brake cleaner etc. Reassemble and then if you must, use a dry lubricant like PTFE spray. The solvent of this evaporates leaving PTFE behind which actually repels dirt rather than dirt sticking to it.

Stephen

IMG_1514.jpeg (4.26 MiB) Viewed 5792 times

[geoberni]

You'll need to confirm the measurements, but I'm pretty sure the MGA used the same M35G starter, there's a diagram on the MGA Guru website: https://mgaguru.com/mgtech/tools/ts214.htm

It is an American website, so the Spec/Details are in American ....

[Mervin]

That's an excellent book Stephen, I have a copy and made a spring compressor using their drawing and measurements.
It works well and far safer than some of the (potentially) dangerous methods some use!

[svenedin]

That's an excellent book Stephen, I have a copy and made a spring compressor using their drawing and measurements.
It works well and far safer than some of the (potentially) dangerous methods some use!

I agree. It's a really good book!

Stephen

[rocco]

Unforutnately I don't have that book and I think it'd probably cost me as much to buy as a used compressor tool would. I have my eye on one at the moment, fingers crossed I will get it.

[geoberni]

Unforutnately I don't have that book and I think it'd probably cost me as much to buy as a used compressor tool would. I have my eye on one at the moment, fingers crossed I will get it.

See the link I posted, it saves finding the book....

[rocco]

Unforutnately I don't have that book and I think it'd probably cost me as much to buy as a used compressor tool would. I have my eye on one at the moment, fingers crossed I will get it.

See the link I posted, it saves finding the book....

Thanks, I did see that and it's what led me to search for that tool. I don't have the option to make it myself.

[svenedin]

Unforutnately I don't have that book and I think it'd probably cost me as much to buy as a used compressor tool would. I have my eye on one at the moment, fingers crossed I will get it.

Fair enough but if you do buy the book it will be useful to help fix many things on the car in the years to come.

Stephen

[rocco]

I'll tell you what would have been useful, knowing that Lucas M35 starter motors are not interchangeable!

Just tried to fit the one that works but discovered that the mounting flange bolt holes are narrower than the one I removed. So, perhaps the only working SM I have is from a Mini or something?

It's rather annoying but there you go, I am learning....slowly.

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20250330_114359_sm.jpg (375.86 KiB) Viewed 2386 times

[geoberni]

I'll tell you what would have been useful, knowing that Lucas M35 starter motors are not interchangeable!

Just tried to fit the one that works but discovered that the mounting flange bolt holes are narrower than the one I removed. So, perhaps the only working SM I have is from a Mini or something?

It's rather annoying but there you go, I am learning....slowly.

Different sub versions of the 'core' model.
Check out all the variants on this link 1949-60. The intro page is very enlightening.
http://www.classicvehicledata.com/wp-co ... 46to60.pdf

[rocco]

Thanks for that. Pity it doesn't list the model I need for a 1970 car but at least I know I have to pay attention to the part numbers.

I did open up the original faulty SM earlier because I am curious to know why it just suddenly stopped working. Nothing obvious but I do wonder about this thin stray wire. It doesn't look as though it should be there. I wonder whether I could just swap the commutator over from one to the other? I'll have to open the other one to see how it looks. If they both have the wedge type brushes then it might work out.

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20250330_141542_sm.jpg (454.48 KiB) Viewed 2229 times

[svenedin]

I am not saying this is the best video to look at but in the absence of a book to guide you this may help:https://www.youtube.com/watch?app=desktop&v=ywF1e3mq2Bo

What stray wire? The thing crossing the pole shoe? I don't think it has any relevance but it should not be in the way of the armature rotation. Isn't it part of the securing of the field coil?

[rocco]

Funnily enough, I watched that video about 2 hours ago!

There is another one, about 30 minutes long by some Aussie bloke which is a good watch but right now, without a bendix spring compressor I'm going to have to leave it until I can get one. Alternatively I may pop in to a local engineering firm who specialises in old British motors and see if he'll take it off for me.

[svenedin]

Ok, I am glad you are not going to try a dangerous home-brew method to compress the Bendix spring!

Stephen