Putting an Alternator on a Farmall M

Can someone tell me how to wire an alternator using a Delco unit that has the 2 spade conectors marked 1 and 2 and a threaded lug on the side marked Bat. I got this tractor and someone had already tried to hook it up but didn't get it all done. Anyway the alternator was toast and I don't want to ruin the new one.

(quoted from post at 16:54:46 06/10/11) Can someone tell me how to wire an alternator using a Delco unit that has the 2 spade conectors marked 1 and 2 and a threaded lug on the side marked Bat. I got this tractor and someone had already tried to hook it up but didn't get it all done. Anyway the alternator was toast and I don't want to ruin the new one.

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On mine, the two spade connectors are jumpered together, and the one wire doing the charging.
One more thing on changing to a 12v system.... my starter would spin and not engage many times. Starter finally had the gear chewed up enough that it was a real PITA to start. Guy rebuilt my starter and changed the field coil to a 12 field and now it starts so fast it almost scares me. This is on a 240U.

(quoted from post at 14:54:46 06/10/11) Can someone tell me how to wire an alternator using a Delco unit that has the 2 spade conectors marked 1 and 2 and a threaded lug on the side marked Bat. I got this tractor and someone had already tried to hook it up but didn't get it all done. Anyway the alternator was toast and I don't want to ruin the new one.

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The #1 wire goes to the ignition switch. It must have a diode or low watage bulb in line. #2 goes to the bat post on the alt and then a heavy 10-12 gauge wire from the bat terminal to the amp meter.

Just did that to my M about 6 weeks ago. No problems with the starter.

Rick

When you say put a low wattage in the line do you
mean like a dash bulb or something like that. Also
when you hook up the low wattage lite how do you
wire it in( One side coming into the positive wire
on the bulb and the ground wire of the bulb to the
wire going out?)

The information in these will make it simple.
There is one with an alternator. The light should be a bulb found in idiot lights, or side clearance lights (not LED) a 10 Ohm resistor can be used, or a diode with the marked band end towards the alternator.
The power for the excite current comes from the ignition. (let us know if it has a mag, it is a bit different)
The #1 terminal connects to the light-Diode- or resistor such that it is in the circuit, not grounded. The light (and the other options) would have one lead connected to the alt #1 terminal, and the other lead connected to the ignition switch where the coil connects.
The coil needs to be new (12 volt for use with no resistor, or have a ballast resistor used to lower the voltage if using the original. One from a mid 60s chevrolet, ot chrysler work well.
This resistor is placed between the coil and the ignition switch.
The coil needs its Negative small terminal connected to the distributor lead. (reversed from original positive ground)
The amp gauge needs to be reversed by switching all wires from one side to the other to show charge when the battery polarity is changed.
The light bulbs need to be 12 volt.
Jim
Bob M diagrams

I will get flamed for this. If you have to buy an alternator go GM 1-wire. IT'S TOO EASY. I have never had one fail or discharge a battery. A quick blip of the throttle to "excite" it. If you go 3-wire the directions that janicholson provided along with Bob M's diagrams will walk you through it.

Good luck,

CT

I want to thank everyone for the helpful info.
Really want to thank janicholson for the diagram. A
picture always helps.

You are welcome. The conversion is a good one. Jim