12 Volt re-wire update (1941 M)

WI Dave · Sep 30, 2009

I've got it all wired up as per Bob's wiring diagram. The starter turns over fine, but no spark at the plugs. No headlights, either. I'm leaving for work shortly, so I'll have to wait until tonight to look into it more.

Theman · Sep 30, 2009

Dave,
When you get back to it, make sure the 'hot' wire through the alternator to the ignition switch is on the battery side of the starter button.

Janicholson · Sep 30, 2009

There must be a wire from the battery positive to the amp meter (usually from the bat wire post on the starter0 there must be no connection to the ignition at all if it is a magneto ignition. It is grounded through the switch to stop.
There must be a wire from the losd side of the amp meter to the light switch, and a wire from the load side to the ignition sw (if and only if it has a distributor ignition with seperate coil. JimN

Shawn in PA · Sep 30, 2009

Your drawing looks like you have a distributor and coil rather than a mag. I agree with Jim. You want your hot wire through the load side of the ammeter. You should really only have 1 wire coming into the ammeter, the one coming from your alternator. All other wires hooked to the ammeter should be exiting from the other post. You"ll know if you hook them up backwards, because the ammeter will show discharge when it actually is charging. Just reverse the wires in that case. If you do have a distributor, you could always run a jumper wire directly from the battery to the coil just so you can hear it run. I realize that may not cure your problem, but it allows you to eliminate other components, such as coil, points, ect...

Janicholson · Sep 30, 2009

Shawn, with respect!!
The alternator heavy wire must be on the load side of the amp meter with the lights and ignition. The other side of the amp meter can have only one heavy wire, but it must be connected to the battery non grounded terminal (either directly, or at the starter terminal where the battery connects) The alternator output should always be through the amp gauge to the battery. JimN

LarryM · Sep 30, 2009

Follow your voltage. Had a customer hook up a battery and left the black plastic cover on the negative post. NOT KIDDING! Get a test light and follow your voltage. Could be a bad igntion switch, ammeter, electrical connection. Follow the voltage!!!

WI Dave · Oct 1, 2009

It has a dist. and coil. Ignition switch is a 2 post kill-switch.

Janicholson · Oct 1, 2009

With respect, no flame. It is technically a 2 post ignition switch because it supplies ignition current to the coil when on. But the term Kill switch is usually discussed in its use with a mag grounding switch. JimN

12 Volt re-wire update (1941 M)

WI Dave

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Theman

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Janicholson

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Shawn in PA

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LarryM

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WI Dave

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Janicholson

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