Hot starter motor

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DCMVan70
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Hot starter motor

Post by DCMVan70 »

Hello

I just bought a 1970 Van, so this is my first question. My starter motor started going very slowly and then I noticed it was very hot - as was the live wire to the starter and the earth back from the engine to the chassis and battery. I pulled the starter off and the rotor was almost too hot to touch even after dismantling.

I recently had a problem where the started stayed engaged, and I put it down to the solenoid sticking when I pressed the black button manually. I have checked all electrical connections are tight

Maybe two questions, do you think I need a new starter or solenoid, or both, and will a standard starter work on a 1275/1300 engine from an Ital, maybe an A+ block (12G3538), I am not sure? I can't find any markings on the starter?

Regards
David
philthehill
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Re: Hot starter motor

Post by philthehill »

I would suggest that you need a new starter motor.
The standard Minor starter motor is quite able and effective in turning over a 1275cc 'A' Series engine.
That is what I use for starting my 1380cc engine with no problems and is always on the button.
Phil

DCMVan70
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Re: Hot starter motor

Post by DCMVan70 »

Phil

Thanks, on order ....

Regards
David
DCMVan70
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Re: Hot starter motor

Post by DCMVan70 »

Back again!

Just got my new starter from ESM and it has a different number of teeth on the gear (9) from the old one (10)!
The mounting plates and length of the bendicks look the same.

I had a better look for serial numbers - the new one is M35G 25092D. The old one does not have the clamp around the end and has the following numbers M350 -----> 12 (might be a O or a G, the last letter is very faint) and 25242A 5 (the first and third 2's are also very faint).

Can I use a 9 tooth starter where there was a 10 tooth starter?
Of course I am not sure if the 10 tooth one was right to start with as it always seemed a bit intermittent?
Can I check the correct number of teeth by counting the teeth on the flywheel?

Regards
David

PS: I had searched for the starter motor numbers, but using google not this Board, and just found this 2014 post and answer ... viewtopic.php?t=68975 ... so please feel free to ignore this one!
philthehill
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Re: Hot starter motor

Post by philthehill »

It makes no difference if the starter dog has 9 or 10 teeth it will work perfectly. The shape and spacing of the teeth allows for either 9 or 10 teeth to be used.

Phil

SteveClem
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Re: Hot starter motor

Post by SteveClem »

Hijacking this post slightly, my starter has always been prone to jamming once in a while. Traveller with 1275 engine and Ford 5 speed box.
Easy to solve by rocking in gear or freeing of with a spanner but it’s always puzzled me. Never happened on my saloon...
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Re: Hot starter motor

Post by SteveClem »

‘Off’.... not ‘of’ :oops:
shoebone
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Re: Hot starter motor

Post by shoebone »

Steve,
Its possible your bendix is sticking on its shaft and would benefit from a good clean, whip the starter out and have a look. the assembly should be clean and dry, free and easy, Its tempting to add a little oil or grease but this allows "clutch dust" and/or other contaminants to attach themselves to the bendix shaft which will result in a bit of a gooey mess that causes stiction. Last time i dealt with a bendix I used brake cleaner to clean and polished what I could with a scotchbright pad.
DCMVan70
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Re: Hot starter motor

Post by DCMVan70 »

All

Just to conclude, I checked the bendix and was free. The new starter sorted it out - spins like a top now.

Thanks
David
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geoberni
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Re: Hot starter motor

Post by geoberni »

Thanks for coming back and telling us the outcome. Far too many people don't do that and leave the subject hanging.
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DCMVan70
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Re: Hot starter motor

Post by DCMVan70 »

Hi All

An update on the starter motor issue - the new one has failed!
I turned the car over with no choke, just to get the oil and fuel moving (mechanical fuel pump), no issues. Then I went to start the car with the choke pulled out and "clunk" - no starter motion.
I tried rocking the car in gear, a thump with the handle of my mallet, but no joy. I then checked the battery, earth, connections etc, but again just a clunk.

I pulled the new starter motor (well 2020 was purchased) and found the following
1. It was a struggle to come out - seems to be stuck inside
2. Would not turn on the bench
3. Starter cog is all mashed up, see picture below

I put the old starter back on to test the circuit and solenoid, all seems to work, but that starter is still pulling too much current and making everything hot.

Question - why am I getting a mashed up cog? (this is a 1275 A+ engine with standard minor gearbox, so I wonder if I have a different flywheel cog? The old starter had a different number of teeth (see above), but this should not matter.

And, what starter would you replace it with - this is a new one from ESM, I could get the old one fixed, or go for a new high torque gear reduction one?

Regards
David

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philthehill
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Re: Hot starter motor

Post by philthehill »

I would be speaking to ESM about the inability of the starter to turn off the car but on the bench. There is no reason that the starter should not turn. The starter may be faulty.
I would suggest that you need to replace the starter ring on the flywheel as well as the Bendix.
There is no need to spend out on a high torque starter. The standard starter is more than adequate.

DCMVan70
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Re: Hot starter motor

Post by DCMVan70 »

Hi All

Phil, thanks for the comments.
Maybe, I was not clear, the new starter does not work on or off the car, so it seems like a new one is in order. Somehow I doubt a 3 year old one would still be covered.

I am still wondering why the cogs are messed up, and what I did wrong and need to think about in the future.
I will try and have a look at the starter ring on the flywheel, I do have a gearbox swap coming up if I cannot see through the hole.

Regards
David
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geoberni
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Re: Hot starter motor

Post by geoberni »

1. It was a struggle to come out - seems to be stuck inside
That makes me think the bendix was jammed on the flywheel; that bendix has an awful lot of damage for only 3 years.
I've no idea about incompatibilities of flywheels etc, perhaps Phil can help there.

If the starter isn't working off the car either, perhaps a bearing has gone, allowing too much off-centre movement and that's why a) the bendix is mangled and b) it won't now do anything.
After 3 years I think all you can do is take a look inside.
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olonas
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Re: Hot starter motor

Post by olonas »

I am not 100% convinced re the 9 or 10 toothed pinnion compatabilty.
The clutch and other parts were changed on my car earlier this year. It had a mismatch of components. 1098cc engine, 948cc engine backplate, 948cc clutch, 948cc flywheel and a 1098cc gearbox. Taking into account all those inconsistences and having a 10 teeth Bendix pinnion it was not certain as to whether the starter ring gear fitted to the 948cc flywheel was correct.
Now it has the correct backplate and a reconditioned 1098cc flywheel from ESM. I have to assume, fitted with the correct ring gear.
I therefore, changed the 10 teeth to a 9 teeth to avoid any possible issues.
As far as I am aware ESM starters are 9 teeth. I did contact them and was told that 9 teeth is correct, not 10. Apparently they have experienced damage with Minor engines using a 10 teeth pinnion.
The above, of course, only relates to the original engine fitments.
I use graphite powder to "lubricate" the Bendix gear.
philthehill
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Re: Hot starter motor

Post by philthehill »

It really does not matter if the Bendix has 9 or 10 teeth. There is enough pitch clearance to allow either to be used.
The number of teeth question has been doing the rounds for some time. I have used both 9 and 10 tooth pinions and have never found any problems in using either.
Here is a link to previous 2016 thread relating to Bendix teeth.
viewtopic.php?p=589933#p589933
The main thing is to use the correct rear engine plate and flywheel combination.
As an aside - to get the starter motor Bendix to fully engage with the flywheel ring gear on my engine I have had to cut out the starter motor section of a 948cc rear engine plate and insert it between the 1275cc rear engine plate and the starter which brings the starter motor forward relative to the ring gear. The point being is that things are not always straight forward and some times 'fitting and fettling' have/has to be resorted too.

olonas
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Re: Hot starter motor

Post by olonas »

Maybe so Phil. I would personally still use the pinnion with the correct number of teeth to go with the application.
As written in my post, ESM did inform me that they have seen the result of the wrong number of teeth causing damage to both starter ring gear and pinnion.
A rough and ready measurement of the pitch (in Foreign!) revealed 9.72mm and 9.16mm for 9 and 10 teeth respectively. A big difference visually between both.
starter pinnions.jpg
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oliver90owner
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Re: Hot starter motor

Post by oliver90owner »

olonas wrote: Wed Oct 25, 2023 11:12 am Maybe so Phil. I would personally still use the pinnion with the correct number of teeth to go with the application.
As written in my post, ESM did inform me that they have seen the result of the wrong number of teeth causing damage to both starter ring gear and pinnion.
A rough and ready measurement of the pitch (in Foreign!) revealed 9.72mm and 9.16mm for 9 and 10 teeth respectively. A big difference visually between both.
starter pinnions.jpg
I see no real difference between the actual tooth clearance of either of those pinions. Metallurgy had moved on a lot since the first use of these bendix starters on Minors. If PTHsats so, you can take his word for it.

I’ve never bothered to specifically select either. Suppliers will always claim their offering is best. I like to discern between ‘reasons’ and ‘excuses’. On this one I definitely agree with PTH, while I would always check the quality of the bendix and also the wear on the flywheel ring-gear. Engines notoiously(?) come to rest with the same segment of ring-gear adjacent to the bendix.

I would never try to mix new with old if either were worn to any extent -and certainly nog beyond service limits.
philthehill
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Re: Hot starter motor

Post by philthehill »

For completeness - the pitch of the starter ring teeth on a 1275cc MG Midget flywheel is 8.4mm.
I am not too worried about the pitch of the teeth on the starter Bendix as I know from experience that both the 9 and 10 tooth Bendix work without incurring damage with the 1275cc Midget/Sprite flywheel.
As I said above it is most important to get the flywheel/rear engine backplate combination right.

DCMVan70
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Re: Hot starter motor

Post by DCMVan70 »

All

Thanks for your input.
I really don't know about the combination I have as was fitted by the PO. I know the engine is an A+, and the gearbox seems like a standard 1098 box with synchro on 1st (well none on second either any more). I have a replacement box ready to go in - looks like I have to get the engine out and see what is going on.

I will also have a better look/compare of the two starters - glad I kept the old one now.

Any tips on recognising what backplate I have?

Regards
David
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