basic wiring fix for wd

[Hoenes]

I'm trying to get an occasional miss out of a wd. The switch was rusty, so I bypassed that. It worked for a while, but now its back. I have a 12 volt battery, and I am still using the 6 volt coil, with the (mopar style) coil resistor. I am going to put a 12 volt coil on, to get rid of any possible loose connections. At what point do you switch to negative ground? (At present, no charging system is up and running) I just take a hot battery with me, which has been fine for Saturday uses. Do I leave it pos. ground, or switch it? What are the bare minimum wires I need (besides hot to coil and starter)?
 

[old]

One set up that way you can go + or - ground as long as the coil is hooked up the same as the ground. No charging system no big deal. Shoot set up that way and you want as little number of wires just a simple hot wire from the battery to the coil and the normal battery cable to the starter is all you need. I have run tractors for months with a none working charging system you just have to charge the battery once in a while
 

[JMS/.MN]

Do you have a magneto or distributor ignition system? If it is original magneto system, the rest of the electrical system has nothing to do with a miss.
 

[souNdguy]

if going 12v, if you ever plan to throw an alt on.. just throw it in negative ground.

I'd get a napa ic14sb coil for about 16$.. get rid of the resistor.. get a new ignition switch.

clean all the grounds .. cables and connections.

you can get a delco 10si alt for about 30$ at the auto store..
 

[BushogPapa]

From solid past experience:...

Even ONE drop of water in the sediment bowl will cause an occasional Miss...
NO idea why, but it will happen..!!

Plugs are New..???
Enough fuel turned to the engine..?
Narrowing the gap on the plugs may make a difference..but, you may have a bad plug wire shorting or cross-firing..??

Ron..
 

[steve(ill)]

12 volt coil is a great idea. Apparently you have a distributor. Just make sure the hot battery terminal is connected to the same hot terminal on the coil. (- to -) or (+ to +)
 

[steve(ill)]

just leave out the ballast resistor on the coil.


 

[WiOrange]

This may be an aside to the wiring issue...

If the miss is isolated to one cylinder you can run a hotter plug there.