Gear Reduction Starter Swap Coil Bypass Wiring (1 Viewer)

[CruiserClay]

Hey guys, need to ask for some help on this (and yes, I have searched for it to no real avail).

Just "inherited" a project 72 Fj40. It hasn't started in 12 years, so working my way through all of the essentials, including ignition parts. At some point a 2F-type gear reduction starter was retrofitted to this unit, and no effort was made to do anything with the ballast resistor bypass system for starting. So the problem I have is that (based on my understanding and corroborated by field tests) the coil gets power with the key on "run" but no power on "start" since the original system was supposed to bypass the ballast resistor and give the coil a full 12v on startup. Then once on "run" position, the coil gets power through the ignition wiring that feeds through the resistor and bumps the voltage down for continuous running. Well, the resistor doesn't get bypassed on this setup; the whole coil and ignition system just goes cold while the starter is engaged, which (I think) means it can't start. How do I remedy this? I've seen a couple of vague references from some 2015 and older threads saying stuff like "just wired in a relay, search up how to do it." Unfortunately, I can't find anything further. If I'm totally missing something please feel free to correct me, and if you have any other threads to point me to I'm always happy to do my homework. Thanks y'all!

 

[Steamer]

The way a resistor by-pass system works.

Turn the key to “Run” and voltage is applied to the resistor and through the resistor to the coil.

Turn the key to “Start” and voltage is still applied as in “Run” but additionally, an auxiliary set of contacts on the starter, applies voltage in between the resistor and coil. Therefore, the resistor is by-passed for starting. Some starters do not have the secondary contacts. Your GR starter probably does not.

You can eliminate the resistor by simply using a coil that works without a resistor. It is possible you may already have one. Sometimes it is called an “Internally resisted coil” but it’s simply a coil with more winding designed to run full time with full voltage. It can be checked with an ohm meter but I don't know the numbers off hand.

 

[Steamer]

the whole coil and ignition system just goes cold while the starter is engaged,

That situation could be a bad ignition switch or a bad connection in the starter circuit. Or, maybe just wired improperly. 12 volts should be applied to the resistor and coil in both “Run” and “Start”.

 

[CruiserClay]

That situation could be a bad ignition switch or a bad connection in the starter circuit. Or, maybe just wired improperly. 12 volts should be applied to the resistor and coil in both “Run” and “Start”.

Thank you for your replies!
I guess I need to start checking wiring then. It did seem odd to me for the coil to receive power from the ignition and bypass totally independently. Good to know that it should still be powered from the ignition wire during "start." Gives me something to do at least. I have been thinking of simply swapping in an internally resisted coil, especially if I get this ignition wire hot at both "run" and "start" as it should be. I don't particularly need the extra power during startup, as we don't get real cold here in Louisiana.
Does 3ohms seem to be in the correct ballpark of resistance to you? Seems like that's what the FSM suggests for internally resisted coils on some of the later models.

 

[Steamer]

This may help.
(pic snagged from a post by GA Architect "Here")