I have very weak magneto performance, probably due to excess crankshaft end play on an otherwise good running engine. Because I'd like to postpone having this good running engine rebuilt for awhile yet, I'd like to run the stock Ford coils off of a small separate 12 volt battery temporarily, but keep everything else electrical running off of the regular stock 6 volt battery, mostly to be easy on my starter bendix.
My question is, can I run the 12 volts to the coils with one fused wire from the postitive post on the 12 volt battery and just run a ground wire to the frame for a common ground for the 12 volt battery as is done with the stock 6 volt battery, or, does the 12 volt circuit for the coils have to be completely isolated from the 6 volt system. (???)
"Ron the Coilman" - those two sets of coils we talked about and that I've sent to you last week should be arriving at your place Monday, Jan. 19th if UPS is true to their word. Perhaps you could answer my question ref proper wiring (and fuse) for 12 volts to the coils and 6 volts to everything else?
Remove the wire from the magneto plug. Hook up the positive wire from your 12 volt battery to this wire. Connect the negative post of the 12 volt to ground. Now you can run your T coils on 6 or 12 volts. When you put the switch in the MAG position, it will run on 12 volts to the coils, but everything else is on 6 volts.
Thanx Jim; couldn't be more simple, huh? Guess I just couldn't get thru' my head that you could use two different batteries in the same car, one being 6 volt and the other being 12 volt, and both using a common ground on the same car. As you can see, my knowledge of "things electrical" leaves a lot to be desired! Thanks again,..........harold
Understand about your coils.
Jim has your question covered very well, just make sure you first faithfully execute the task in Jim's first sentence or the 12 volt battery won't last very long.
Ron the Coilman