Electrical Discharge on Older 12-volt

Anonymous-0 · Nov 28, 2009

I purchased a 1962 tractor recently. It has an original 12-volt system. The seller re-wired it to get it going after it sat for several years and obviously did not do it correctly. The tractor will start-up with a fully-charged battery, then show a buried-needle DISCHARGE on the Ammeter while running. If cables are left attached, the battery will be dead next time you attempt to start it. Seller also happened to mention that after he rewired it, both headlamps blew-out (complete with smoke) upon being hooked-up. Can somebody tell me what to look for as the most-likely mistake that was made by the seller?

Thank you.

funky_g00 · Nov 28, 2009

From the sounds of it you obviously have a short to ground somewhere. You will need to trace all the wiring and check for one of two things either a bare or pinched wire grounding out on the frame, or a "HOT" wire that was accidently hooked to "GROUND". If all this checks out look at the voltage regulater I have seen this cause both a slow discharge on the battery as well as send excessive amps thru the lighting system to cause bulbs to blow if hooked up wrong or faulty. Hope this helps you.

fixerupper · Nov 28, 2009

A tractor from that model year will have a generator unless it was replaced with an alternator at sometime in it's life. If it has a generator it could be the field terminal is grounded to the frame somehow. If the field terminal on the generator is shorted to the frame the generator will run wild and put out way too much voltage. If the lights are turned on the excess voltage will blow them out. They get real bright and then poof.

Check the wires going to the voltage regulator. The 'F' terminal on the regulator should have a wire going to the 'F' terminal on the generator. The 'A' terminal on the regulator should go to the 'A' terminal on the generator and the 'B' or 'BATT' terminal on the regulator goes to the ammeter and should be hot at all times. Sometimes the regulator has a 'L' or 'LOAD' terminal that has a wire going out to feed the lights. None of these wires should have bare spots touching the frame. Let us know what you find. Jim

Anonymous-0 · Nov 28, 2009

More details on the tractor are needed to allow a better help line. Some tractors in 1962 ran on 24 volts, some ran on 12 volts, some positive ground, some negative ground. Not having polarized the generator can allow it to build up with reversed polarity and would cause that severe discharge for a while but the generator and regulator life will be short. It will be best to find a proper wiring diagram for your tractor and then see about the changes made and wire it like it was intended. There isn't much complication to 1968 tractor wiring once you take care of the polarity details.

Gerald J.

buickanddeere · Nov 28, 2009

(quoted from post at 02:13:34 11/28/09) I purchased a 1962 tractor recently. It has an original 12-volt system. The seller re-wired it to get it going after it sat for several years and obviously did not do it correctly. The tractor will start-up with a fully-charged battery, then show a buried-needle DISCHARGE on the Ammeter while running. If cables are left attached, the battery will be dead next time you attempt to start it. Seller also happened to mention that after he rewired it, both headlamps blew-out (complete with smoke) upon being hooked-up. Can somebody tell me what to look for as the most-likely mistake that was made by the seller?

Thank you.

Make, model, alternator, generator, 12V,24V ???? You are located beyond the range of my Crystal Ball and ESP.

Electrical Discharge on Older 12-volt

Anonymous-0

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funky_g00

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fixerupper

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Anonymous-0

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buickanddeere

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