12 volt conversion

wingnut2nd

Junior Member
I have installed a 12V one wire Alt on my project 1929. I have a 12 volt coil, battery, and just want to start and run the engine. Does anyone have a simple wiring diagram to make a temporary wiring set up for the staring and ingnition system using a toggle switch and the stock staring setup. I am using a negitive ground.
 
Hi Wing,
I see you have 4 posts above. If no one has said this to you yet, welcome to the forum. There are a number of posts about this conversion you are talking about, and I believe some of them even contain wiring diagrams.

However, to answer your question directly, all you need is a direct cable to the starter switch, and a direct but switched line to the ignition coil. Be sure that the coil polarity is correct, the red + wire to the + terminal on the coil, and the black - wire from the distributor back to the - terminal on the coil. I'm not completely sure here, but if you are using an original type condenser, you might want to consider a modern condenser.
I'm really not sure if modern condensers are pole-sensitive.

I do not know exactly why you are making this modification, but if you are doing it to operate modern automotive electronics, I would highly advise you to consider a two or three wire conversion for your alternator. Reason: one-wire alternators come on line when a certain rpm is achieved, and they come on line with a "bang" of an electrical surge. This is not healthy for modern electronics. The field coils of a two or three wire alternator are excited with the first revolutions of the armature, and they come on line "soft". Give it a little thought, and good luck with your project!
 
Does this help? You can ignore the temp gauge and fuel pump.
 

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Does this help? You can ignore the temp gauge and fuel pump.

You left out the fuse. Many people put a fuse block on the starter. Without a fuse a short circuit burns up wires. All the parts houses carry the fuse block. They also carry a nice electric diagram with all the colors on it. Very handy.

 
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The squiggly line on my diagram is a fuse, I should have labelled it. I have the starter-mounted fuse holder.
 
If you would like the information on how to convert the single wire alternator to a 3 wire send me an email jrelliott42@gmail.com. If you do make the conversion, just remember to pull the fuse when you stop for a while as the fields of the alternator will still be energized and draw a small current from the battery.
 
Not be contrary but the battery drain on a one wire system should be negligible. Advice given is sound however.
We make an awful lot of one wire systems for equipment, industrial and farm applications.
Delco has been using one wire apps all the way back into the 70's.
I looked for the service bulletin and as I recall about seven years to drain a battery.
I would agree that many after market regulators can stick and we do see them.
I would use a Transpo D10SE that eliminates the diode trio.

I would pull the fuse over winter storage or battery cable just for good measure.

I would not advocate the fuse that vendors sell that attach to the starter.
The fuse can pop up out of the holder and if the car is under power it isn't pretty.
At least be sure that you do not use the longer fuse as the screws that attach the wires will prevent it from locking into the holder. Too that end make sure the fingers grasp the fuse solidly.
I use ATC style fuses.

Personally I do not use a master switch.
 
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