1968 F100 points elmininator problems

[Bfdcapt]

Hey everyone. New to the forum and truck ownership... I just bought a 68 F100. The guy I got it from put in a points eliminator for me but had trouble with it. He said the truck runs on 6volt and the eliminator needs 12 so it had to be wired direct to the battery.... which he did via alligator clip. Problem is that the only way to shut the truck off is to pop the hood and disconnect it from the battery every single time. So I wired a relay switch so I didn’t have to do that and it’s working. Problem is that since using the relay it’s havijg trouble starting each time. When direct to the battery it would fire right up, now it turns over and over and over and then finally starts after several attempts...
Any advise?

[colnago]

When cranking, the 12V gets to the coil over a different circuit, so your relay isn't getting any power. Can you check the voltage on the "S" lug of the starter relay when you're cranking? If you have power, you can run this to another relay.

I don't get how you can have everything working on 6V, though. What does he mean by that? Do you have two 6V batteries in the truck? What alternator do you have? The only thing I've seen with the points eliminate is bypassing the ballast resistor.

Welcome to the family!

Joseph

On edit, the right way for it to work is for 12V to go to the ignition switch. When you turn it to start, it sends 12V to the coil on one circuit. When you let it go to run, it goes through a ballast resistor on a different circuit. This drops the voltage to around 9V to the coil. With the points eliminator, you can send the full 12V (If your coil can handle it). It sounds like your wiring is sending the full 12V during run, but you have a lower voltage when cranking. I still don't understand the 6V thing, but that's probably not enough to light things up. Post more info when you can.

[Bfdcapt]

When cranking, the 12V gets to the coil over a different circuit, so your relay isn't getting any power. Can you check the voltage on the "S" lug of the starter relay when you're cranking? If you have power, you can run this to another relay.

I don't get how you can have everything working on 6V, though. What does he mean by that? Do you have two 6V batteries in the truck? What alternator do you have? The only thing I've seen with the points eliminate is bypassing the ballast resistor.

Welcome to the family!

Joseph

On edit, the right way for it to work is for 12V to go to the ignition switch. When you turn it to start, it sends 12V to the coil on one circuit. When you let it go to run, it goes through a ballast resistor on a different circuit. This drops the voltage to around 9V to the coil. With the points eliminator, you can send the full 12V (If your coil can handle it). It sounds like your wiring is sending the full 12V during run, but you have a lower voltage when cranking. I still don't understand the 6V thing, but that's probably not enough to light things up. Post more info when you can.

Thanks for the replies. So the “6v” info was from the guy I bought it from... it’s not 6v... but either way, I need 12 at the eliminator which for some reason I’m not getting from the relay. My solution was to simply run a switch. I ran power direct from the battery to the switch and the switch to the points eliminator. I throw the switch and start her up. Then when I **** her off I just hit the switch again. It’s working like a charm. I just can’t imagine that everyone that uses a points eliminator has to do this...

[sargentrs]

When installing an electronic ignition, I always add a 12v relay and trigger it via the original ignition circuit wire.

[colnago]

When installing an electronic ignition, I always add a 12v relay and trigger it via the original ignition circuit wire.

This is on my to-do list for this week. I've been running with a DSII for the past six months, and I just put the larger dizzy cap and rotor today. The next step is to mount a relay to send 12V to the coil, then increase my plug gap to 0.044".

Joseph

[colnago]

Thanks for the replies. So the “6v” info was from the guy I bought it from... it’s not 6v... but either way, I need 12 at the eliminator which for some reason I’m not getting from the relay. My solution was to simply run a switch. I ran power direct from the battery to the switch and the switch to the points eliminator. I throw the switch and start her up. Then when I **** her off I just hit the switch again. It’s working like a charm. I just can’t imagine that everyone that uses a points eliminator has to do this...

Just remember that there are two circuits from the ignition (key) switch. The "ignition" circuit sends a full 12V to the coil. The "run" circuit sends 12V through the ballast resistor, so you get ~9V to the coil. If you have a different switch that you're throwing, then you're bypassing something, somewhere. Sargentrs is suggesting to use a relay, triggered off of the 9V "run" circuit, to send 12V from the battery directly to the coil.

Joseph