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electrical prob?

Old Aug 2, 2013 | 09:49 PM
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bronkntrukholik's Avatar
bronkntrukholik
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electrical prob?

i haven't made it over to my buddys house yet to check out his truck, but here is what happened, he has a '79 f350 4x2 dump w-351 and 4spd, his wife was driving the dump in the field when baling hay, she stalled it then got out of the truck letting the key untouched in the on position and in gear, a few hours later they returned to the truck and it was moved about 50 yards. At this point the truck had no juice, he put the battery on charge and now the truck cranks when the key is in run position, he had the starter, the selonoid, and ignition switch all checked and all are working properly, what would be other things to check?
 
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Old Aug 2, 2013 | 11:14 PM
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The S (start) terminal is getting power when in run. It sounds like the I and S wires on the starter solenoid are reversed...
 
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Old Aug 3, 2013 | 07:53 AM
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The battery drained with the key left in RUN because the coil stays grounded out in that state. It would have been a 4-amp draw on the battery for several hours. For an old and/or poor-quality battery, that could kill it.

Regarding the truck cranking in RUN, there is more to the story than you're telling us. Someone was messing with it while trying to get it to start, and changed something. HIO's idea is one explanation.
 
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Old Aug 4, 2013 | 11:50 AM
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Ok so i talked to my buddy again, the truck was running great until the key was let on and somehow moved on its own the short distance. when he found it moved with the key on and now having a dead battery, he tried jumping it and that is when it started crankin with the key in ON postion. After that is when he had the starter,selonoid, and key switch checked. maybe the selonoid or battery could be causing this? just wondering what would make the truck crank while in gear with the key on all by itself?
 
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Old Aug 4, 2013 | 12:40 PM
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HIO already answered that question. You're going to have to get a voltmeter or test light out to investigate.
 
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