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Help Electrical Problem

  • Thread starter Thread starter 65shelby
  • Start date Start date Aug 12, 2008
6

65shelby

New Member
Aug 26, 2003
42
0
0
Aug 12, 2008
#1
  • Aug 12, 2008
  • #1
I am in the process of restoring a 65. I have replaced all the wiring harnesses and moved the battery to the trunk. I have also switched to the Ford Motorsports mini starter. When I installed the new mini starter I thought I would be slick and use an original 65 starter wire from the fender solenoid to the starter solenoid. I did this so I wouldn't have to shorter the "special" positive cable that came with the new starter. I believe this was a mistake because something happened when I turned the ignition key to start. Everything was fine when I turned the key to on, but when I turned it to start, there was a sound like the starter had moved a little but then everything went dead. I now have no lights anywhere on the car whereas before all interior and exterior lights were working. So, now I have replaced the wire from the fender solenoid to the starter solenoid with the "special" one that came with the starter. But still everything is dead and now I'm trying to figure out if something else got fried. What I have been able to determine with my multimeter is that I have 12.7 volts on the batt side of the fender solenoid with the + batt cable and one of the black/yellow wires is attached to it. I also have 12.7 volts at the starter solenoid. But....As soon as I touch the other black/yellow and yellow wires (these are the 2 that go to the voltage regulator), the volts on the batt side of the fender solenoid drop to ZERO. So I guess this means I have a ground problem somewhere along the black/yellow and yellow wires. Is it possible that by using the wrong starter wire, I fried the voltage regulator and that has created the ground problem. If anyone can help me diagnose where the problem is and how to fix it I would appreciate it.

Thanks
 

jikelly

20+ Year Stangneter
Jul 9, 2003
872
53
99
Lubbock Tx
Aug 12, 2008
#2
  • Aug 12, 2008
  • #2
Is there any chance there is a fuse somewhere along the battery or starter cable?

Check the wires coming from the battery. I know when something similar happened to me it was a worn starter cable that would short out to the frame when I tried to start the car. Course if that were going on you would smell stuff burning.

It could be a bad voltage reglator though. That's not bad because they are only like 10 dollars.
 
6

65shelby

New Member
Aug 26, 2003
42
0
0
Aug 12, 2008
#3
  • Aug 12, 2008
  • #3
There's no fuses along those lines that I am aware of. There was no smell of anything burning when this happened. The fuses in the fuse panel all look good, but I think they are primarily for the accessories and wouldn't cause all the electrical to shut down. I think I'll go get a voltage regulator and see if that solves the problem.
 

69gmachine

Member
Dec 2, 2004
576
2
19
Southern Maryland
Aug 12, 2008
#4
  • Aug 12, 2008
  • #4
65shelby said:
I am in the process of restoring a 65. I have replaced all the wiring harnesses and moved the battery to the trunk. I have also switched to the Ford Motorsports mini starter. When I installed the new mini starter I thought I would be slick and use an original 65 starter wire from the fender solenoid to the starter solenoid. I did this so I wouldn't have to shorter the "special" positive cable that came with the new starter. I believe this was a mistake because something happened when I turned the ignition key to start. Everything was fine when I turned the key to on, but when I turned it to start, there was a sound like the starter had moved a little but then everything went dead. I now have no lights anywhere on the car whereas before all interior and exterior lights were working. So, now I have replaced the wire from the fender solenoid to the starter solenoid with the "special" one that came with the starter. But still everything is dead and now I'm trying to figure out if something else got fried. What I have been able to determine with my multimeter is that I have 12.7 volts on the batt side of the fender solenoid with the + batt cable and one of the black/yellow wires is attached to it. I also have 12.7 volts at the starter solenoid. But....As soon as I touch the other black/yellow and yellow wires (these are the 2 that go to the voltage regulator), the volts on the batt side of the fender solenoid drop to ZERO. So I guess this means I have a ground problem somewhere along the black/yellow and yellow wires. Is it possible that by using the wrong starter wire, I fried the voltage regulator and that has created the ground problem. If anyone can help me diagnose where the problem is and how to fix it I would appreciate it.

Thanks
Click to expand...

If I understand your wire routing correctly, there is nothing wrong with that approach. I have the same set up. On my car, the battery in the trunk goes to a cut-off switch, and then to the underside of the fake battery's positive terminal. The fake Autolite battery positive terminal then goes to the fender mounted solenoid so the wiring is routed just as it was from the factory. A reproduction starter cable goes to the mini starter solenoid. A jumper goes from the mini starter's battery connection to the small terminal so the mini-starter solenoid is activated at the same time the power hits the big terminal. My starter is used from a wrecking yard and it's starting to die a natural death, but it's been working this way since I put the engine back in earlier this year.

I know this doesn't help a lot, but it means you need to look elsewhere for the problem. If the starter is bad it could be pulling too much current.
 
6

65shelby

New Member
Aug 26, 2003
42
0
0
Aug 13, 2008
#5
  • Aug 13, 2008
  • #5
Well it looks like the problem was a bad battery ground. I took the battery out of the trunk and used jumper cables to hook it up to the solenoid. I wasn't getting any power until I hooked up the negative jumper cable to the bare metal radiator bracket. Then all the lights came on. So I moved the battery back to the trunk and sanded the negative ground down to bare metal removing a fair amount of dirt and rust in the process. Then I rehooked up the negative ground to the new clean spot on the chassis and I'm back in business again. I'm glad it was something simple.
 
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