Question with 12v conversion

[that8nguy]

so I finally decided to 12 volt convert my Oliver 77 but I'm waiting for the mini alternator come in so for right now I just got a 12 volt coil put new points in a new battery and unplugged the 6 volt charging system so it's not charging while it's running but at night I just put the maintainer on the battery. when I get the alternator I'm going to switch ground obviously to make it negative ground instead of positive and that's where I'm confused. let's say I went out to the barn and hooked it up to where the negative is now ground and positive was live would it mess anything up? so basically what I'm asking is can I go make it negative ground without doing anything else other than switching around negative to being grown and positive to being live?

Edit: what happenes if I put an alternator on it but don't switch to negative ground?

 

[Jim.ME]

Likely you will need to swap the primary wires on the coil so + gets power from the switch and - goes to the distributor. If you have an ammeter the wires on it will likely need to be swapped to the opposite terminals.

 

[BarnyardEngineering]

Yes, don't get hung up on "ground" and instead pay attention to the +'s and the -'s. Connect + to + and - to -.

For example, the coil has a + and a -. Right now the coil's - is connected to the wire from the switch, because the battery - is connected to the switch. The coil's + is connected to the points, because the points connect to the frame of the tractor, and the battery + is connected to the frame of the tractor.

If something isn't marked, it doesn't matter. For example, the ballast resistor for the coil (if you have one), doesn't care. The ammeter doesn't care either, but it will read backwards if you don't switch it.

 

[that8nguy]

Yes, don't get hung up on "ground" and instead pay attention to the +'s and the -'s. Connect + to + and - to -.

For example, the coil has a + and a -. Right now the coil's - is connected to the wire from the switch, because the battery - is connected to the switch. The coil's + is connected to the points, because the points connect to the frame of the tractor, and the battery + is connected to the frame of the tractor.

If something isn't marked, it doesn't matter. For example, the ballast resistor for the coil (if you have one), doesn't care. The ammeter doesn't care either, but it will read backwards if you don't switch it.

this is what I needed thank you

 

[BarnyardEngineering]

this is what I needed thank you

By the way, connecting it up backwards won't hurt the coil, but it won't produce as strong a spark.

 

[used red MN]

Edit: what happenes if I put an alternator on it but don't switch to negative ground?

Don’t do that you will immediately damage your alternator or wiring or both. Alternators convert AC current into DC using heavy diodes, which are essentially electrical one way valves. If you try to force negative current into the alternator output diodes backwards to the positive of the alternators frame as it is bolted to the engine the diodes essentially create a direct short. Just don’t do it.

 

[Jim.ME]

Edit: what happenes if I put an alternator on it but don't switch to negative ground?

Smoke show! (Unless you purchased an alternator built for positive ground>)

 

[that8nguy]

By the way, connecting it up backwards won't hurt the coil, but it won't produce as strong a spark.

Smoke show! (Unless you purchased an alternator built for positive ground>)

ok I will switch then

 

[Jim.ME]

ok I will switch then

Barnyard Engineering was referring to the coil would not be hurt if connected backwards, it would just produce a weaker spark. He was not saying the alternator would not be hurt if connected backwards.

 

[that8nguy]

Barnyard Engineering was referring to the coil would not be hurt if connected backwards, it would just produce a weaker spark. He was not saying the alternator would not be hurt if connected backwards.

yea I understood that

 

[BarnyardEngineering]

Barnyard Engineering was referring to the coil would not be hurt if connected backwards, it would just produce a weaker spark. He was not saying the alternator would not be hurt if connected backwards.

The part about connecting the alternator backwards was added after I answered the question...

Yeah, you can't do that. If you do your research though, the BAT terminal on the alternator is the +, so... what did I say earlier?

 

[Northvale PA]

I had all my 6v generators rebuilt to 12v. I put them all in as positive ground. Polarize the voltage regulator and use the correct color on the cables to avoid confusion in the future.

 

[that8nguy]

I had all my 6v generators rebuilt to 12v. I put them all in as positive ground. Polarize the voltage regulator and use the correct color on the cables to avoid confusion in the future.

I may do that.....how much did that cost about if you don't mind me asking?

 

[used red MN]

I may do that.....how much did that cost about if you don't mind me asking?

Figure in the wheel barrow full of regulators you will go through. That might be an exaggeration but there is some truth to it. That’s the beautiful thing about internally regulated alternators they are nearly “set it and forget it.”