Installing a gear drive starter in a Model A

fordcragar

fordcragar

Senior Member
Would this be a simple install. I heard somewhere that the ring gear had to be turned around; which wouldn't make this a simple install. This would be a Model A with a "B" engine. I wouldn't think that it would be a problem, but I thought I would ask to see if anyone has any insight into this swap.
 
My thoughts: in a perfect world, yes the ring gear should be reversed. I'm willing to bet that the gear drive starter will work just fine with the ring gear in the stock orientation.
Many gear drive starters have been installed in cars without reversing the ring gear. My guess is that ignorance is bliss in this case.
 
I've posted this before, but here goes again. The Model A engine tends to stop in one of two places on its own, about 180 degrees apart. Not always, but the majority of time. Consequently, the ring gear teeth in those two areas get the most use by the Bendix drive on the starter shaft. The drive really bangs against those teeth hard! Over the years these teeth get worn down and/or gouged from this harsh contact, making it more difficult for the Bendix drive to grab them and turn the flywheel. You'll hear a gnashing, but the flywheel doesn't turn. In extreme cases, the starter shaft just spins without grabbing any teeth.
Until the ring gear can be changed or repositioned on the flywheel, a temporary "cure" is for the driver to "force" the engine to stop in a different place. That means holding your foot on the brake pedal while letting out the clutch with the transmission in gear. That will stall the engine in a different spot on the ring gear and allow fresh teeth to engage with the Bendix drive. I did this for a year with my '31 Roadster until such time as I was healthy enough again to change ring gears. Not an afternoon job!
Alternately, if the drive will not engage the ring gear teeth, put the transmission into third gear, take off the emergency brake and push the car forward a foot or so. This will turn the crankshaft and place a different set (and presumably better) of teeth facing the starter. Then you're good to go - this time, at least.
To permanently fix this condition, some guys will heat the ring gear and rotate it on the flywheel so that a rarely used set of ring gear teeth now will absorb the brunt of the starter engaging. It's academic whether rotating the ring gear is easier or more advisable than simply replacing the gear. In either case, the ring gear must be heated almost cherry red to move or remove it. I usually just cut off the old gear, but heat the new one to install it. Ring gears are not all that expensive, so that's probably the better way to go. Just be sure the chamfer edges on the teeth face the REAR of the car or else the Bendix drive will not be able to engage the teeth and turn over the crankshaft.
Marshall
 
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The geardrive starterv engages its pinion in the flyeheel gear8before it starts turning. It also engages from the front of the flywheel.
For this reason it will work fine by not reversing the ring gear or considering ring grear wear.

John
 
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Marshall V. Daut said:
..... Just be sure the chamfer edges on the teeth face the REAR of the car or else the Bendix drive will not be able to engage the teeth and turn over the crankshaft.
Marshall
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That is for the stock ring gear and starter. It pulls the starter gear forward into the ring gear.
The bendix in the modern gear drive starter pushes the starter gear rearward into the ring gear. The geared starter has chamfered teeth so it will work without reversing the ring gear.
 
ModelA29 said:
That is for the stock ring gear and starter. It pulls the starter gear forward into the ring gear.
The bendix in the modern gear drive starter pushes the starter gear rearward into the ring gear. The geared starter has chamfered teeth so it will work without reversing the ring gear.
Click to expand...


This is correct. No need to worry about the ring gear.:)
 
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