Smokin
 

OK so the car won't shut off with the key, so I buy a replacement sw and install...no change.
Go start it yesterday AM and it starts ok starts to smoke behind the dash. I shut down with a master cutoff sw I have under the dash. Unscrew the chrome dash cover and feel for hot wire. I find the red wire to the ign sw is hot. So I remove it and see if the car will start/smoke.....it does both.
This getting serious, so again I hit the cutoff sw and ck the heat on all the wiring behind the chrome dash. All the wires are hot.
When I replaced the ign sw to start all 3 wires to it were put back in the same pole location, nothing crossed or mis placed.
So I have a direct short some where in this very simple wiring. The ammeter looks intact not burned that was my 1st thought for a short but not sure.
I can't keep activating the sys or something going to melt down and it will happen very quickly.
The car is 12v system.
I guess I could disconnect everything but not sure about ability to re wire correctly. The car has a new wiring harness through out except for a couple of add on red wires to the coil...all installed by PO. red wire to coil is only one currently disconnected and the black wire going from the ign sw to the ammeter seemed to smoke the most.
I am going to disc that black wire and try that next. If the car runs and doesn't smoke I think its the ammeter gone bad if not, not sure where to go next.

Re: Smokin
 

It shouldn't be too hard the problem, simple system. You can do it.

One place to look is the back of the switch [ I'm assuming its an aftermarket type] to make sure it isn't making contact with the fuel tank. This is kinda common. Make sure the wires are intact and in good shape and insulate between switch and tank. Most times just bending the switch contacts will fix that problem.

Re: Smokin
 

As Patrick stated, pull the instrument panel away from the dash (gas tank) and look for signs of contact on the tank. If you see it, then the bend and tape of connections is an easy solve.


Since you are running a 12v system, have you changed over to negative ground? If so you can also open the battery access panel, loosen the positive terminal a bit so you can quickly pull if off to end 'short' while you chase down the problem. As the positive terminal runs right to the starter I have an aftermarket fuse plate there as well. Only saying that is a safeguard I have, and I also have an inline fuse leading to my alternator.


Good luck and let us know what the problem turns out to be.

Re: Smokin
 

I would advise to quit smoking as it can lead to health problems.

Re: Smokin
 

Well , his car sure has some health issues right now doesn't it. :D

Re: Smokin
 

I put two layers of electrical tape behind the switch on the gas tank as extra insurance when the same issue happened to me.
And yes, I'm using an after market switch (for now), as most of them are junk

Re: Smokin
 

Burner....are you saying the key ign sw was contacting the dash?
The problem is getting worse the more I get into it. Wire in bundle going to the starter got so hot on one one of my "lets see if its fixed" startups that it caught fire.
All future troubleshooting is restricted to visual/on paper only.
Car is pushed out of the garage to work on but at 85 I'm struggling to move it.

Re: Smokin
 

We're all saying the switch connects/wires may be contacting the dash/fuel tank. And have said how to fix it.

Checking the wiring is not hard. A wiring diagram is readily available.

Re: Smokin
 

Bend the tabs on the switch so that they cannot contact the metal behind them. Insulate the contacts with several layers of electrical tape.

When done with the above, disconnect the battery and use an ohm meter to test the wiring, looking for shorts. Do not test the wiring by trying to run the car.

Ask someone with electrical experience to help.

Re: Smokin
 

The car as originally wired should not have a wire from the ammeter to the
ignition switch. Can you post some pictures of the engine area so we can see
what modifications have been made to the wiring.

Re: Smokin
 

I agree with Bob, there shouldn't be a wire from the switch to the ammeter. Also, there should just be two wires off of the ignition switch, power from the coil and the wire to the points. My guess is that the extra wires from the PO are at fault or at the very least confusing all of us here.

Re: Smokin
 

Unless, of course, the switch is wired to power the coil when on like a modern car. In that case a wire will run from the load side of the junction box to the switch and then to the coil. A wire could bypass the junction box and run directly from the load side of the ammeter to the switch.

There is a short somewhere.

Re: Smokin
 

The car ran well for over a year, until recently. After I change the coil (only coil wires swapped) problems began. I would like to put up a number of pics but my clunky camera and the resizer pgm that keeps hiding my pics.
Here are a couple. The 1st pic shows wire completely burned through, a black wire out of the loom to the starter.
The 2nd dash pic shows a fabric covered black wire that really got hot going from ign sw to ammeter.
This the setup the has run w/o any problems for past year.
I have replace the new hi v coil, with orig coil just to try to get back to some workable baseline. I will remove the wire from the ign sw to the ammeter and not sure where to go from there.
So far there is only one destroyed wire which I can easily replace and a couple more I'll replace out of caution.. But that doesn't fix the problem.

Re: Smokin
 

Gene,

Sit down with a pencil and a piece of paper and draw out your wiring diagram. Trace each wire. Label the color of the wires and show all the components, such as the ignition switch and ammeter and coil and points. Then, with the battery disconnected, measure the resistance to ground of each wire. When you do this see that the points are open or put a piece of paper between the points. Also do it with the points closed. Measure the resistance to ground with the ignition switch off and with the ignition switch on. The problem should become clear.

Re: Smokin
 

There's your problem. As others have mentioned, you should not have a wire from the ammeter to the ignition switch. There should be a wire (short/black) going from the terminal box to the negative side of the coil. The other side of the coil (positive) should have that red fabric wire connected to it. That same wire is connected to one side of the ignition switch. The other red plastic wire should be connected to the other terminal on the ignition switch.

Re: Smokin
 

Ok slowly but surely I'm diving in. The wire between ign sw and ammeter is gone, I notice how loose the 2 poles of the ammeter are to their case, removed the ammeter took it apart and the posts can touch the case, I know that's not right, also the needle is welded to gauge face.
Now whether all this caused or are the result of the overheat is ??

Re: Smokin
 

Here is a wiring diagram.


http://https://www.fordbarn.com/foru...7&d=1632783797

Re: Smokin
 

Thanks Bob
The armored cable that goes to the distrib is there to grd the system with key in the off position,Right?
At the dash end my cable is cut off and an elec wire is attached to the cable. The wire goes to the coil and the metal cable end goes into the distrib???

Re: Smokin
 

OK seems the switch is controlling the hot side of the coil instead of the ground from the points. It needs to be wired this way if you are using the ignition switch to
supply switched power to some accessory.

Re: Smokin
 

Yes, your coil is switched on the hot side with the points connected directly to (-) coil terminal. Battery is connected from the ammeter to the switch (burned black wire). Since the wire is burned, I'd say the short has to be past the ammeter.

The "accessory" is the alternator regulator - the smaller red wire goes to pin 1 of the alt. connector through a diode so the alt begins charging without having to rev up the engine.