Newbie here. A friend of mine is asking ME about wiring on his '32 Ford 2-door sedan. It's a pretty cool car that he has owned for 60 years (he's 75) and it's nearing completion of its 3rd build. More on that later when I get some pics. Here's where we are: we have a typical 4-pole aftermarket switch. I don't think we're going to use this one because it has ON, START, ACCESS and OFF. What would we do with ACCESS these days? Anyway, the flathead motor runs a magneto. We found a relay in the box of electrical parts removed 20 years ago. I think what the original electrical guy did was wire a normally closed relay to the ground of the mag. Turn switch to ON and the relay breaks continuity; OFF and the relay closes grounding the mag. This seems fail safe to me and a pretty easy way to get the job done. Any advice? Oh, BTW, I'm Zeke over on the GJ but there was already a Zeke here.
A better idea ( and pretty failsafe) would be to use a Vertex Mag switch directly from mag to a good ground. The relays seem to have more problems etc..... However you cant just use any switch its got to be a good one .........
Thanks, Bubba. We were trying to avoid a 2 step shut down of the motor for the less intuitive. After I posted I thought someone might mention an overall battery kill switch which is always a good idea. Yet, that mag would continue to fire. The good thing is this rod runs a LaSalle tranny so he can always stall it with the clutch. At 75 YO the owner is doing this for posterity and his 2 sons. I don't think the sons are into this stuff at all, but they say they will keep the '32 in the family. I think you can see why I want to keep it simple.
I run a mag a ( vertex ) I just use a on/off switch the red airplane looking ones. I have never had any problems in 5 years.--TV Mine is wired direct to the mag and ground.
Got a Vertex/Joe Hunt magneto in my 32 with a 409. I did exactly what you are thinking about doing with the relay. I wanted a normal on start run key switch. The run contacts on the ignition switch, energize the relay coil, ungrounding the mag "P" terminal. In the event of a problem (never had one) I can remove the "P" lead thumb screw from the mag and off we go.. I used a 30 amp silver contact, triple pole double through relay and paralleled two of the NC contacts to do the grounding.
I'll check the rating on the relay we found. However, I might recommend we get a new one. My friend loves to use old original stuff. I think he would have bought used wires if he could have found them.
The Jalopy Journal
