Weird starter motor problem

Bad back

Junior Member
Hi all, I'm sitting here scratching my head. 1929 Model A pickup not been touched for many years.
I've removed the starter , stripped it, cleaned it, etc and on the bench it runs very well. Bendix moves freely and all seems good.
However when I fit it to the engine the starter still turns well but refuses to engage. There are no grating/weird noises.
The engine does turn over by hand (so definitely not seized).
Any ideas anyone????????
 
Is there a chance you have a stripped tooth on the flywheel gear? Or when you tore the motor down did you possibly mis-assemble so the motor is running backwards (I'm not an electrical type so I don't know if this is possible, others can comment).
 
Put the car in third gear and push it forward a foot or two or if you have a hand crank, use it to turn the crankshaft a couple degrees. This is not to break loose a Bendix drive that is jammed. That's not the problem here. This merely bumps the flywheel a couple teeth away from the Bendix drive it presently sits against. Now try the starter. As JayJay says, the ring gear may be missing a tooth or two, or the teeth in that area of the ring gear are worn down. The Model A engine tends to stop in one of two places when the ignition key is turned off. That means, these same teeth are the ones that the Bendix drive strikes when starting the engine. That messes up the teeth over time so that the Bendix drive can't grab ahold of the ring gear and spin it. The engine may be stopped opposite a bad section of teeth. By bumping the flywheel, a fresh set of teeth will be opposite the Bendix drive. If the starter catches the ring gear and turns the engine over, you know that the ring gear needs to be replaced or rotated 1/4 turn. If the starter still doesn't work, remove it and check the bolts on the Bendix drive. One may be loose or sheared. Also check the condition of the Bendix spring for a break or distortion.
Marshall
 
A depression era remedy for the "stopping in the same position" was to remove the flywheel, mark the flywheel/gear for location, then carefully remove the ring gear by sequentially "tapping" the gear around the perimeter. It's possible to incrementally "walk" the ring gear off.

Once off, heat the ring gear up in an oven (300F) and then "drop" the ring gear back in position - BUT HAVE THE MARKS 90 DEGREES OFF from the former position.

I say drop. It may need careful persuasion similar to tapping it off on removal.


Joe K
 
And yes, if you've reversed the field connections in reassembly, the starter will turn backwards - and the bendix won't "climb the incline" and engage the ring gear.

You can check the starter out of the car. Have + and - as it would be electrically connected normally.

And find a way to "hold" the starter other than in your hand. A broken thumb is not fun.


Joe K
 
Hey,


I had experienced that the Bendix could not engage properly in cold outside temperatures because it was incorrectly installed with an oil that was too thick.
 
Thank you everybody for the suggestions. I checked and did all the recommendations and now feel like a complete fool. Took the starter out (again getting quite good at it now) and noticed the end of bendix assembly moved on the shaft. I hadn't removed this when checking/cleaning the starter. Removed the bendix from the shaft and there's the problem - no woodruff key on the shaft!!!! New one on order.
Again many thanks everyone for your inputs really appreciated.
 
Oftentimes it's the little things that can cause big headaches with these old Model A's. 'Glad you found the solution. Your local hardware store should have been able to supply the correct woodruff key size using the starter shaft slot as a guide. But if you were ordering other parts anyway, no big deal. I would have ordered two or three of those little guys because they are easy to misplace on the loose.
M.
 
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