M 12-v Conversion - Now Going This Way!

[gitractorman]

So, My buddy Dennis didn't exactly do what I thought. He had checked my generator and said it was charging ok. When I went to pick it up, all he had done was that, hadn't rebuilt it. So, I asked him to go thru and rebuild it, along with the starter and magneto.

He just called and said the armature is bad in the generator, and it's probably a couple hundred $$ to replace the armature. So, now it looks like I'm going to do a 12-v conversion.

Nothing else on the tractor is wired. The magneto is in good shape, and the starter is in good shape. I'm planning to replace all the gauges anyway, so a new ammeter isn't a big deal.

The magneto just has a wire to the kill switch, and the generator just had 1 wire to the ammeter, so the wiring harness on this M was pretty simple to begin with.

I have this idea. I'm thinking of buying a second can for the steering column support where the ammeter and light switch is, and mounting the two together (left/right of the steering column). Keeping the right side for the ammeter and light switch, but using the left one for a key switch and maybe an hour meter. I already have an IH key switch (actually 3 of them) from 1960s Cub Cadets, and I have a brand new 12v starter solenoid. This setup would get rid of the kill switch and push button starter button at the bottom of the steering column support.

Let me know what you all think, also, let me know if you have a good suggestion for an alternator. I've seen the Steiner kit, and saw how lots of folks flip the generator bracket upside down to use as the alternator bracket, tucking it up under the hood

I'm interested to hear what you all have learned and have found to be a good 12-v conversion.

Thanks,
Bill

[Eugene]

I like and have used the single wire alternators for several years.

The only bottom bracket conversion, self made, was for a standard Cub. The bigger tractors, WD Allis Chalmers, were almost a direct bolt in.

[oldfarmkid]

The left/right can mod. sounds like a fun project with a practical result.

[gitractorman]

Hey guys,
Been a while, but I"ve made a lot of progress on the M.

I have it all wired, and came up with a really simple dash/key switch layout, by replacing the factory light switch with two toggle switches.

I figured the old 6-v switch wouldn't work anyway with the new 12v system, and this just seemed to make a nice, simple layout.

So, with it all wired, I was going thru with an ohm meter to check all my wiring, and ran across something confusing.

It appears that the magneto is always at ground, meaning the kill wire (when disconnected at the switch) is always showing continuity to ground. The brass nut where the kill wire attaches also shows continuity to the body of the magneto and to ground.

So, I didn't think to check this before tearing the tractor down, as the mag was working fine, and I cannot find any references anywhere, but can anyone tell me if this is correct? Maybe someone can go out and disconnect their kill wire at the mag and see if that brass nut is showing continuity to ground?

Thanks in advance!
Bill

[Jim Becker]

I assume your points are closed and it is grounding through them. I'm not sure if the circuit through the coil would give the same test result with the points open, probably.

[gitractorman]

I guess I should have noted that I had the mag rebuilt and he said everything checked out good, and I've not tried to start the tractor (matter of fact, haven't even put the battery in it yet). Maybe I should have tried starting it before posting, but that's the engineer in me, trying to test everything before I give it a try.