Battery was backwards.. farmall BN

T-Nason · Apr 18, 2022

Well guys I messed up.
I put the battery in my BN backwards. 6 volt with a magneto fired it up it started and I realized what I did. It fired up normal but I noticed the amp gauge wasnt charging. Just sitting straight up and down. How bad did I mess up and what can I do to fix it? Ive heard things of having to drain the battery or repolarize the generator?

timcasbolt · Apr 18, 2022

(quoted from post at 10:29:58 04/18/22) Well guys I messed up.
I put the battery in my BN backwards. 6 volt with a magneto fired it up it started and I realized what I did. It fired up normal but I noticed the amp gauge wasnt charging. Just sitting straight up and down. How bad did I mess up and what can I do to fix it? Ive heard things of having to drain the battery or repolarize the generator?

hen you say backwards, do you mean that you connected the negative terminal of the battery to ground?

grandpa Love · Apr 18, 2022

Shouldn't be too bad... Polarize your generator. Can't hurt much with a mag.

used red MN · Apr 18, 2022

You have likely harmed nothing. You will just need to install the battery correctly, which if you have an original 6 volt system is positive to ground or the chassis of the tractor. Then with a short piece of wire momentarily jump the connections of the Gen terminal and the Bat terminal on the voltage regulator. Draining the battery and recharging it would only be necessary if you had a dead battery and then you crank started the engine and the generator recharged the battery back up in a reverse charge, which it does not sound like you have done this. Had your tractor been converted to a 12v system utilizing an alternator a backwards battery connection immediately damages the alternator.

T-Nason · Apr 18, 2022

Yup, I connected the positive to the starter and negative to the
ground.

redforlife · Apr 18, 2022

I agree with used red. Switch things back around right, and then re-polarize the generator. Likely didn't do any damage. Especially if you didn't smell anything getting hot or smoke.

Post back with details if what's been said already, doesn't make everything OK. As in, the generator will then no longer charge at all (the right or the wrong way). If damage WAS done, that'll be how you'll know. No generator charging at all, anymore.

rvirgil_KS · Apr 18, 2022

but I noticed the amp gauge wasnt charging

Assuming it was not charging, no harm should have been done.

Why was the battery removed? Not charging before? I would not be surprised if you still have a no charge problem. As others indicate install battery positive ground and then polarize generator.

Check voltage across battery. Full charge should be 6.3 volts. Start engine, rev to at least half throttle and check battery voltage. If 7 volts or above it should be charging. With fully charged battery the ammeter will show very little indication.

If voltage does not go up when running:

1. Ground field terminal when running, should show significant increase in charge rate. If so you have a bad regulator control, either in voltage regulator box or the combo light switch.

2. If still no charge, leave field grounded and jumper from ARM terminal on generator to the lead from the battery. If charge now increases you have a bad cut out. If still no charge suspect generator, wire,or grounding problem.

Janicholson · Apr 18, 2022

Grounding the field on a Ford is incorrect. The field takes voltage at the F terminal to energize (or polarize). B circuit system!!! Jim

J Hamilton · Apr 18, 2022

I think he's working on a Farmall not a Ford

Janicholson · Apr 18, 2022

True it is. Jim

Battery was backwards.. farmall BN

T-Nason

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timcasbolt

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grandpa Love

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used red MN

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T-Nason

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redforlife

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rvirgil_KS

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Janicholson

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J Hamilton

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Janicholson

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