Won't start after electrical prob!

[jonkay]

Returned to Houston from the LEBC Round-up in April - turned the key on my 77' and it tried to start then died. I turned the key again and a cloud of smoke poured out from under my dash. Upon inspection, I found the red/blue wire coming from the ignition switch burned almost beyond recognition both under the dash and in the engine bay. The wire was burned all the way through the ignition switch harness and the male & female plug connections at the firewall. I replaced the ignition switch harness with a harness from a 1963 Ford Falcon (a suggestion from someone on this board) and the wires seem to match up and the plug fits. I bypassed the plug connection at the firewall and ran it straight to the "S" terminal at the solenoid. I still got nothing when I turned the key despite the fact that my lights worked. I tried to run a new ground from the solenoid to the engine block (another suggestion from this board) but had no luck. On a whim, I ran a new ground from the voltage regulator to the engine block and now I get power when I turn the key but it won't start. It will start for a second when I spray the carb (Holley T/A) with starter fluid but dies after it burns off. Fuel issue? Choke? Some other electrical gremlin I created in my uniformed wrenching? Any help to start the 5,000 lbs paper weight in my garage would be very much appreciated!!

 

[firehawk]

Do you have a mechanical or electric fuel pump?

 

[Broncobowsher]

It will start for a second when I spray the carb (Holley T/A) with starter fluid but dies after it burns off. Fuel issue?

Do you have an electric fuel pump? Does it run? Are you out of gas?

From the sounds of all the jumpers you are adding and the mixed results when you do so, you have some major eletrical issues that you are trying to patch around.

 

[jonkay]

I'm 99% sure it's mechanical (tell me how I can be 100% and I'll post back in a few seconds!). By the way, I was born and raised in Berkley (family still lives there) hows the weather up there?

 

[Broncobowsher]

Follow the fuel line from the carb. Does it go to a pump mounted next to the oil filter? That is the mechanical pump.
Keep following the fuel line back toward the tank. If you get to something that has 2 hoses and a wire or two attached, that would be an eletrical fuel pump.

 

[jonkay]

100% manual (thanks!). There is no question about the electrical issues, Broncobowsher. That, obviously, was one of the areas I got cheap on in the rebuild and I am kicking myself now! If I can get it started I'm taking it to the guy who wired it for me to find out what the deal is!

 

[oleguy74]

question? after rewireing,you get it to start right?when it starts ,key goes to run it dies?never mind thinking of another trbl.do you have points or electronic ign.?

 

[jonkay]

oleguy74,

I have not been able to get it to turn over since the burned wire unless the carb is saturated with starter fluid. Then, it will turn over for just a second and then die. I haven't gotten started long enough to see if it is a run/start igntion issue.

 

[Viperwolf1]

There are 2 red-blue wires coming from the ign switch, one to the solenoid "S" post and one to the duraspark 3 wire connector. If this other wire is burnt also it ain't gonna start.

Any idea on what caused the short in the first place?

 

[jonkay]

Any idea on what caused the short in the first place?[/QUOTE]

This is my biggest concern, right now. I have no idea what caused the short as I just returned from a 700 mile trip and the truck was in my garage at the time of the problem.

The burnt wire I found was going to the "s" terminal. The ignition switch harness had a total of four wires coming from it: a thick yellow wire, a red/blue wire, a green/red wire, and a orangish-brown wire (coming form the same connector in the harness as the green/red wire). This is assuming the PO did not replace any of these wires (colors) in the past.

 

[Viperwolf1]

The power on that wire came from the ign sw so the point on the far end near the solenoid would have been the problem area. If you can see where the last burnt piece of wire was then that's where your short to ground was. If it was burnt all the way to the solenoid then the solenoid is your problem.

There should be a red-blue wire on your duraspark module and it should go to the same point on the ign sw as the other. The older harness probably doesn't have it. There is also a brown wire on the module that needs to go to a "hot in run wire". This would have went to to a splice under the dash and met with the end (not ign sw end) of the red-green wire from the ign sw. Also probably not on older harness.

 

[oleguy74]

big yellow is power. red/blu goes to S on solenoid and ign box. red/green goes to pos. coil, green/red to volt reg. red/green is run

 

[jonkay]

Viperwolf,

The wire was burnt down at the ignition switch harness, but not the solenoid. I replaced the harness but should I also replace the ignition switch? I did not replace it because I am getting power on the start, I just can't get it to turn over. I took this as the ignition switch being ok (it's still out, replacing the switch will be no big deal).

oleguy74,

If the green/red wire to the volatage reg is not connected properly, could this cause my troubles? Again, it is trying to start but it won't turn over. I am not sure if that is a voltage reg issue or not. (the green/red is the only wire I have not physically traced to make sure it is not burned or disconnected somewhere - I'll do it in the morning if you think there is a chance).

 

[jonkay]

After reading over these posts, have I screwed up by by-passing the plug at the firewall? Everyone keeps talking about a second red/blue wire. oleguy 74 says one goes to the "s" terminal (which I have replaced because it was smoked about 10 inches on the engine side of the firewall as well). Does this second red/blue wire connect at the male/female plug connection at the firewall? If so, it has no connection since the red/blue wire from the igntion switch is being run straight to the "s" terminal (by-passing the plug). Would this cause the engine to not turn over? (I think I know the answer to that question!)

 

[Viperwolf1]

Your ign sw may be ok. Like I said the sw was the source of the 12v to the red-blue wire. It would have burned from there to where it was shorted to ground. Where the burning ended is the short.

A bad green-red to regulator won't prevent starting, just charging.

 

[oleguy74]

red green goes to ign coil.from sw run/start.green /red goes to reg.that lead only works to chargeing ckt. you guy's type faster than me.

 

[Viperwolf1]

After reading over these posts, have I screwed up by by-passing the plug at the firewall? Everyone keeps talking about a second red/blue wire. oleguy 74 says one goes to the "s" terminal (which I have replaced because it was smoked about 10 inches on the engine side of the firewall as well). Does this second red/blue wire connect at the male/female plug connection at the firewall? If so, it has no connection since the red/blue wire from the igntion switch is being run straight to the "s" terminal (by-passing the plug). Would this cause the engine to not turn over? (I think I know the answer to that question!)

This is on your 77 correct? Yes there are 2 red-blue wires on the same post on the ign sw. The other one goes to the driver's side inner fender where the duraspark module is.

 

[Viperwolf1]

red green goes to ign coil.from sw run/start

It just goes to the run post. If it went to both run and start it would cause the starter to keep running.

 

[oleguy74]

both go to start.

 

[jonkay]

This is on your 77 correct? Yes there are 2 red-blue wires on the same post on the ign sw. The other one goes to the driver's side inner fender where the duraspark module is.

I have the original ignition switch harness (or at least the harness that I removed) in my hand as I type and it has ONE red/blue coming from the harness. I just checked the wiring diagram for the 75-77 that I have been using and it does show two - like you say. The diagram shows a green/red (i have that one), a red/green (i don't have that one), two red/blues (i have one that runs directly to the "s" terminal), a green/black (i have that one), a purple (i am assuming that is my brown), and a yellow (i have that one). I am ABSOLUTLEY positive this is a 77', am I dealing with an earlier model wiring harness? If so, where does the second red/blue wire to the ignition box connect?