Pertronix III & Flame Thrower III Installed
(10-06-2015, 05:46 PM)1969_Mach1 Wrote: Good to hear. I may be off base but I am thinking since the timing changed so much after installing the Pertronix, moving the distributor housing to reset the timing repositioned the rotor tip in relation to the contacts on the dist cap when the spark occurs. This might have increased air gap between the rotor tip and contact on the dist cap. That plus corrosion and the issue cropped up. That large timing change is still a bit odd to me.

It sounds like its ready for a new distributor cap and rotor. However, check the terminals on the cap occasionally see if they corrode very quickly.

I thought your tach was disconnected to install the Pertronix? If so the horns should have no affect.

My tach is disconnected. The tach wire is still connected on the ignition switch but disconnected at the coil. The new wire is spliced to tach wire right at the ignition switch. So I'm not sure why tach needle moves when I press horns. Before I replaced the horns, the cables were disconnected to the old ones. When I plugged them in with ignition off, I'd get a click. You know, the natural sound of a broken horn. But the car would not start. It just kept cranking away. So naturally I figured a short inside horns. I was hoping to save myself a headache with new horns and 12v supply to coil but now i have to figure out what's shorted.
The tach wiring is pretty well isolated from any other circuit in the car. Your car is a non A/C car so you should be able to get to the two wire connector for the tach from under the dash. Unplug it for now and tape up any bare ends to be safe.

Is it only the horn that causes tach needle movement? Does it move when then there is any other electrical load, lights, etc. turned on and off?

"Fix one break two." That's why more times than not cars of this age go through complete restorations. When these cars were only 20-25 years old you can easily drive them and fix things as they occur.

I did see the alternator and oil light flash a few times but it only happened one time while I was still playing with the timing. The dash lights occasional do not come on or come on then go off after a while. All this started happening when I changed to the pertronix. Its either a strange coincidence or somehow there is a short. I didnt check my connections to the fuse box yet which is still my next step. There are a few wires that plug (or jammed) between fuse connectors and fuse. Thats how i bought the car. Maybe one of them is loose. I do have headlights, ashtray light, working brake, oil and alternator light as well as interiori/door lights. Just intermittent dash lights.
I thought you tapped into the + wire feeding the tachometer at the ignition switch? That would have no affect on all the other electrical issues you now have.

Those wires wedged between a fuse and the connector are definitely not original. Is there an aftermarket radio or something using those? Or was it a patch repair somebody did?

Almost time to rewire the car. Or like I did, get a wiring diagram, then on the workbench unwrap the entire wire harness, replace any bad wiring and connectors and make repairs with soldered and shrink tube connections. Then you'll put an end to the electrical issues.

Yep I did splice to tach wire + feed right at ignition switch. I have no idea why those jumper wires would be there at fuse box. There isn't any after market radio or anything else other than the electronic choke on edelbrock carb.

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