Electrical Theory question

[cmann250]

I didn't want to muck up the BS thread

I did an engine swap on a lawn mower not long ago. Now I'm trying to figure out the ignition. The original engine had a "regulator" in the ignition circuit. I have the regulator in front of me. It has 3 wires coming out of it that I'm calling "left", "hot", and "right". See picture.



When I connect my ground probe to the "hot" wire and the hot probe to the left wire and I get 56x ohms of resistance. I do the same to the right wire and I get 54x ohms. No other two wires show resistance so I believe that there are no other ways to make a circuit.

What do these wires do? How do I tell which is power and ground? Of course I could have kept the original engine to find what they do, but its gone. I recall that my tractor has a regulator in the ignition circuit because back in the day coils weren't as good as they are today.

Why don't they teach this chit in schools?

[PToombs]

Is that the one that goes to the current engine or the previous one?
Are there 2 wires coming out of the shroud? I think that's a rectifier, AC from the stator comes out to the yellow wires, and the rectifier converts it to DC on the red wire which goes to the battery, lights, electric clutch or whatever. Pics of the wires on the engine may help.

[cmann250]

This is from the original engine. There are 2 wires coming from the new engine. One is a ground and the other I assume is to the coils. Another wire comes from the engine and feeds 12 v to the red wire.

I assume if I feed the coils 12 v directly, it'll smoke them.

[BILTIT]

It is a regulator/rectifier in one package.

[cmann250]

So it's impossible to hook it up backwards?

[BILTIT]

Not impossible, just be sure to hook the wires up as shown in the picture.

[cmann250]

I know the red wire needs 12 v to it. On the new engine, one wire is grounded and one isn't.

How do I tell which wire on the engine goes to which yellow wire on the regulator?

[BILTIT]

Nope the red wire has 12v coming out of it, the input is the two yellow wires from the stator.

Sounds like you already have a rectifier on the new engine as it only has two wires, Its a different setup.

[PToombs]

Biltit showed what I was talking about. Maybe you should pull the shroud and make sure where the wires go. One may go to the coil to for a ground to shut it off.

[cmann250]

I'll have to dig into it. Owning a 12 v has not helped sharpen my electrical skills.

Thanks to both of you.

[PToombs]

I'll have to dig into it. Owning a 12 v has not helped sharpen my electrical skills.

Wow, that's sad! It should have helped immensely!