C1 Ignition Wiring

[Jerry G.]

I'll try to keep this short. While doing a body off, I replaced all the wiring on my 56, w/manual tranny. My problem is that I smoked the brown ignition harness wire from the resistor to the switch while bumping the distributor to set the timing mark. I've heard you can do this by leaving the key in the ON position too long, but I only had it on for 10 to 15 seconds. No other wiring went up in smoke. Bad swithch? Bad resistor? Bad ground from doing the body off? Beats me, so I'm wondering if this has happened to anyone else. Thanks in advance. Jerry

[Bob Simard]

C1 Ignition Wiring

Can't help with the wiring, but don't use the starter to set the timing mark. It is way too frustrating. Just put the tranny in high (3rd) and push on the top of the front wheel (forward or backward) while watching the timing mark. Very easy, fast, and precise.

[William C.]

Re: C1 Ignition Wiring

Short in the wire fron the switch to the resistor, pinched somewhere, only way it can happem as described.

[Jerry G.]

Re: C1 Ignition Wiring

Thanks Bill. Could it possibly have a short from the wiper motor since it is tied to the same side of the resistor? Or, a short in the switch, if that's possible. I didn't have this problem before, but I had everything removed from the car of course. Maybe I caused it somehow. Jerry

[Richard M.]

Re:C1 Ignition Wiring

So I always thought that the brown wire should have been a heavier gage by design....

It's only a 18 gage right?. It powers the ignition(via ballast resistor, except when cranking) and wiper motor. Since you didn't have the wipers on(I'd assume), the problem may be a bad connection at(or inside) the ignition switch or ballast resistor contacts, or at the coil +. It's possible dirty contact points in the distributor can be an issue. Any additional resistance caused by a bad connection will add load to the circuit, therefore more current through the wire. Being only 18 gage, it can only take so much. If you look at many original C1's brown wire coming out of the firewall, it may have been heat stressed over time.

Other possibilities:
Bad engine grounds. Are all of your heavy gage black wires to the engine attached tightly? Loose grounds are often at fault.

Bad dist condenser(open circuit)? It eats up voltage spikes so the points don't burn out from arcing due to extra current.

Your ballast bypass wire to the solenoid? When cranking, battery is supplied directly to the coil via the green wire from the starter solenoid. It also drives the brown wire through the ballast and tries to reach the same potential. Any loose connections can cause uncertain results, as current finds its shortest path to ground.

Hope you find it so you don't ruin another harness,
Rich

[John H.]

Re:C1 Ignition Wiring

Is your ignition shielding in place? If the coil isn't oriented properly in its clamp and you push down on the shielding when installing it, you can touch the coil (+) terminal against the inside of the upper shield and short the ignition circuit to ground through the shield, which lets all the smoke out of the wire.

[Greg S.]

Re:C1 Ignition Wiring

Been there, done that on my 62. Put the top ignition shield on, turned the key to start and watched smoke rise from under the hood. My wire is still serviceable but lost points in judging. Can the brown wire be replaced without replacing the harness entirely? It is wrapped in a heavy cloth loom with several other wires.

[Dave Suesz]

Brown wire

is common as a stock color. Just pull an inch or so out of the main and use a solder and shrinktube repair to connect it, then work the repair back into the harness.