Model A How-to: Testing the Starter

[@biondanishgenomeinstitute8193]

Ted, what is the right starter rpm? my 12V starter hits the flywheel way too hard, even though it got 12V field coils. Maybe I got 6V coils by mistake. I have not yet measured rpm (can be done with a free "app" called RPM meter), but I can compare if I knew the right rpm. Opinions on the web vary, strangely. One can reason that if the motor wants 200 rpm to start, and if there 15 times as many teeth on the flywheel as on the starter, then the starter should be at 3000 rpm. But I could not find measurements on the net.

[@Teds_Garage]

In my newest videos I have the starter installed… you can see and hear the starter… and I actually have a 8 volt battery… The 6 volt batteries turn pretty slow… but remember the Ford Model T was mostly hand crank (electric starter was optional after about 1919\20..). I’ve heard 6v starters using 12v…. and even jump started Model A’s using 12v…. It’ll hit the flywheel hard and spin fast… but I don’t think I would want to keep doing that… eventually the starter will burn out or destroy the ring gear on the flywheel… Sounds like you’re running a 6v starter on 12v…. from your description and how hard the bendix is engaging… It could be your bendix is very loose/worn if the starter is not turning the engine fast. Once engaged in the ring gear how fast does the starter turn the engine? The bendix slides on a shaft… so it could just be a worn bendix… Interesting… let me know what you find…

[@biondanishgenomeinstitute8193]

@@Teds_Garage Thanks for the reply. Since my message I replaced the enclosed bendix drive I had (the new type with no visible spring) with a new old-style bendix. Now it sounds less harsh, but runs too fast still. I did not measure rpm, but comparing by ear a 6V car with mine, I would say mine spins 50-100% faster despite the 12V stator coils. So the problem is half fixed. A electronics savvy friend thinks just a few windings of thick wire put in series in front of the starter will dampen speed. We will try something. Also met a guy with a Snyder catalog with a big resistor for the starter in it, but Snyder does not have it today.