help with electical problem
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help with electical problem
i have a 1969 ford f 100 and i just put a new batt alter and voltage reg in it . my problem is that my truck starts to stall when i use the head lights and turn signals. how can you find the short?
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From: Virginia
With the engine off, do the headlights work normally with no smoking wires? If so, then I suspect you have a grounding problem. Make sure you have a short piece of wire bolted to the engine block, and then bolted to the firewall sheetmetal. Also make sure you have another going from the block to the frontend sheetmetal around the radiator support. Make sure yo grind the paint off around the ground wire terminal bolt.
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Joined: Nov 2004
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From: sunny fla sometimes windy
Pull all the fuses out except the ones you need to run the motor, add one at a time
and try to recreate the problem each time. If that don't narrow it down then invest
in a multimeter and check the voltage on the positive side of the coil with the lights
off and then with them on without the engine running then try it with the motor
running, If you see a big difference in the voltage you have a weak spark and there
could be a number of causes. How are the wiring contacts condition pretty clean
or corroded and crappy? some contact cleaner and dielectric grease might not be a
bad idea and it could help prevent future problems and is worth the work!!
and try to recreate the problem each time. If that don't narrow it down then invest
in a multimeter and check the voltage on the positive side of the coil with the lights
off and then with them on without the engine running then try it with the motor
running, If you see a big difference in the voltage you have a weak spark and there
could be a number of causes. How are the wiring contacts condition pretty clean
or corroded and crappy? some contact cleaner and dielectric grease might not be a
bad idea and it could help prevent future problems and is worth the work!!
Moderator
Joined: Jan 2001
Posts: 56,950
Likes: 2,718
From: Virginia
The best way to find a short to ground is disconnect the battery cables, and hook up a small battery charger to the cables. If you have a short, it will trip the circuit breaker in the charger. If it does, then unplug part of the wiring harness, let the circuit breaker cool, and then try it again to isolate the problem.
You didn't say if the headlights worked with the engine off?
You didn't say if the headlights worked with the engine off?
Moderator
Joined: Jan 2001
Posts: 56,950
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From: Virginia
If they work, then I do not believe you have a short. It could be something else, but I still suspect a grounding problem. Just take a jumper cable and clip one end to a clean place on the engine, and clip the other end to a clean place on the frontend sheetmetal, and see if the problem goes away.
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New User
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i will try that today. i need to jump start it every day. i got an other ? if i put my meter on the battery cable and check for countinuaty will i have it ? excuse my spelling
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Moderator
Joined: Jan 2001
Posts: 56,950
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From: Virginia
You might get continuity from the neg of the battery to the sheetmetal, but it might be a false reading unless you have a very sensitive meter. It could read ground through another component, which is what I am guessing your problem is.
Do you have the original points ignition system?
Do you have the original points ignition system?
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New User
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it does have org points.itried the pulling one fuse at a time and i pulled the first two fuse and nuthing happen,so i tried the next three and the voltage on the battery droped big time . it went down to 9 vts
