wireing problem

BigTone · Posted: Mon Oct 08, 2012 8:37 am Post subject: wireing problem

Im used farmall bobs wire diagram to rewire the M, but I noticed that it has a positive ground...I have a 12 volt generator with a negative ground, does anyone have a wiring diagram for that or what do I need to change to make the circut work correctly? When I took all the old wiring off I noticed that my father in law had a wire going from the negative side of the coil to the distributor but the wiring diagram has it the other way, now im stumped and I cant get the timing light to come on at all....any help is greatly appreciated, thanks. ~Anthony

old · Posted: Mon Oct 08, 2012 8:39 am Post subject: Re: wireing problem

Only difference in the + ground system to the - ground system is which side of the battery is ground and the coil needs to have the + side going to the distributor

Janicholson · Posted: Mon Oct 08, 2012 9:01 am Post subject: Re: wireing problem

As old indicates there is only your preference.
The generator needs to be polarized (as per John T instruction) to set it to generate with your choice of polarity. The amp gauge needs to be connected so it goes negative when the lights are turned on when the tractor is not running.
If negative ground (like todays cars) the coil should have the negative terminal connected to the dist. if positive ground (as it came from the factory) the coil should be positive to the dist.
The wiring is only different in those areas. Jim

BigTone · Posted: Mon Oct 08, 2012 9:35 am Post subject: Re: wireing problem

I have no juice at the generator or on the Gen terminal on the voltage regulator and I did what the instructions said, "touch a small wire from the batt terminal to the gen terminal and expect to see a spark." Did I do that wrong jim?

Janicholson · Posted: Mon Oct 08, 2012 11:49 am Post subject: Re: wireing problem

If you touch the Bat terminal on the reguletor (coming from the Amp gauge) to the Gen terminal (it could say Arm on it) again on the regulator, there should be a spark. Assumes the battary is connected, engine off, and all wires connected as they should be. Test the Bat terminal to assure yourself it has battery voltage there. then try it again. if no spark, the generator might be paint isolated from the tractor, or have bad brushes, or stuck brushes, or a not grounded voltage regulator. John T procedure is complete and good. Jim

Allis Chalmers	Case	Cockshutt	Farmall IH	Ford 8N,9N,2N	Ford
H. Ferguson	John Deere	Massey	Minn. Moline	Oliver	All The Rest