I was driving my 69Z28 today when all of the sudden it flat out dies. Tried cranking it right after it died and it would crank but would not fire. Pushed it into a parking spot and started looking around under the hood and noticed that the neg wire on the coil was frayed through. Fixed the wire on the coil and hit the key... would crank but still not fire, then it started smoking around where the wiring harness plugs through the firewall. Now it is home in the garage and will not even crank... just smokes now. Anyone have any ideas?

Also all fuses are good

Any insight is appreciated!

Thanks

Disconnect the battery immediately, unwrap the harness, inspect and see what is causing the problem. A worn through casing allowing a live wire to ground will cause your problem. And perhaps lead to more damage. I'm not an elecrical diagnostician, but others here are.

The battery is already disconnected. If a wire is grounding or shorting out shouldn't it pop the fuse though? All of the fuses are good in the car. Before I go tearing into things I want to make sure I am not missing something simple.

I had a similar issue, not broken wire but smoking from the harness. Ended up being the engine harness resistance wire to coil (white) had at one point been spliced together and re-taped. Once harness was unwrapped it looked very bad...evidence of severe heat and insulation cracking....

Replaced the harness w/ one from Rick's and problem went away.

Tom

Check your points see if they are opening and closing while the engine is cranking.

The points would not cause it to turn over would it? I am more concerned about getting it to turn over again.

No, but it will cause the wires leading to the ignition coil to melt if they don't open and the key is on. It will also cause it not to start.

The purple wire from the ignition switch (clutch safety switch) to the starter solenoid is in the same bundle of wires that run across the top of the firewall, so if you melted the ignition wire, you may have also melted the wire to the starter solenoid.

Just came in from working on the car for a bit. It is cranking over again... makes me feel a little better. Took the cap off the dist. and the points are sticking... what causes this? Should I just replace the points?

So, is it the origonal 40 yr old wiring harness? This could be the tip of the iceberg. You may want to look into replacing the entire wiring harness. Smoking wires indicates a short or overloading. Fuses and fuse links are supposed to protect circuts from totally melting down, but it sounds like maybe something is still shorting. As far as your run problem, yes replace the points and condenser at minimum. Don't go buy cheap Chinese stuff either. If your main battery to engine ground is weak, then other smaller wires will be the next place the ground path will go and they cannot handle the amperage of a starter. Keep us posted.

It is not an original harness. I opened it all up and none of the wires have melted through the insulation... All of the wires look pretty good but the white one does get hot when the key is on and the points do not open. I think the smoke was coming from all the electrical tape that was wrapped around the wires. I will go through the car and check all of the grounds before I take it out again... picking up points tomorrow. Car usually runs great, this whole thing has been a surprise.

Other opinions are appreciated!

Switched over to the Pertronix system today and still no luck. The engine cranks fine but still will not fire and the wires are still smoking. I just checked the coil and I am not getting any power to the terminals on the coil. Any other ideas?

Points don't open because the point set rubbing block is worn, no lube, or the dist cam is worn, no lube and high tension spoint set.
Once a large amount of current goes through the contact set, the points are burned together.

Wire manufacturer packed in an extra load of smoke.

Power to the coil comes through the dist module and the module gets its power from the bulkhead connector under the brake master cylinder and from the ignition switch from the body bulkhead connector from the horn relay buss bar from the junction block next to the battery from the bat post.

Switched over to the Pertronix system today and still no luck. The engine cranks fine but still will not fire and the wires are still smoking. I just checked the coil and I am not getting any power to the terminals on the coil. Any other ideas?


Can you give me some details about your switching over to a Pertronix System?

Recently, my old Pertronix Unit went bad. The engine would still run but was only firing on 5 cylinders. I replaced the old Pertronix Unit with a new Pertronix Unit & she went back to hitting on all 8 cylinders.

At idle & up to 5200 rpm she purrs like a kitten. However beyond the 5200 range she begins to misses & stumbles.

Tell me about your electrical source for your Pertronix Unit? I have tried this in two scenarios. One being the original step down wire from my engine harness/ the other by bringing in a "key on" 12 volt source directly to the Pertronix Coil, thus jumping over to the unit in the Distributor. Somewhere I'm just not doing something exactly correct and I'm not sure what?

Our problems are not identical but they are most certainly similar. Where are you getting your power supply for the Pertronix Unit?

If it won't crank, could it be that you burned up the starter in the process of trying to get to fire up due to an ignition problem? Could be two totally unrelated issues.

Here's a couple of issues I've personally encountered that may help.

On one of my first distributor rebuilds, I over-greased the distributor shaft before putting it back in the housing. After a few days of running, some of my grease slung out and got between the breaker points and it wouldn't run.

Another lesson learned was when I replaced the cracked and brittle IGN wire with a new wire. I didn't realize it was a resistance wire. Eventually the coil overheated and cracked.

Run a 12 guage wire from the battery directly to the pertronix unit after you disconnect the 12 volt wire coming from the ignition switch, and then crank the engine to see if it will start. If it starts you have a problem somewhere between the ignition switch and the wiring going to the distributor. You may have to pull the switch to see if there is any wires that are loose or burnt at the back of the switch.

I ran a new positive from the switched 12v inside the car and a new negative directly to the coil and now I have power to the coil and the pertronix unit. The car STILL will not fire though... no spark at the plugs and the coil is brand new.

Gettin very angry with this problem.

Any new ideas?

Is dist body getting a good ground connection?

A quick check for coil check is to connect power to + terminal and a wire from - terminal loose.
Hold coil high tension wire, with insulated pliers , about 1/4 inch from a good ground.
Take loose - wire and tap to ground, on - off, spark should happen with power on. Multiple touches to ground, multiple sparks.

Your present set-up, either module is not grounded or bad module.