Battery Explosion & Other Following Electrical Issues

[Haoleguy]

A good friend of mine has an older Kubota M series tractor from an early 2000s model year. Recently he noticed his battery was low on water and he added tap water to fill. Well yesterday while he was spraying his vineyard the battery blew up. To keep working he put in another battery he had on hand to keep going. Once he started the tractor he finished the spraying and then found that he could not shut off the tractor until he starved it of fuel. So my 2 questions are: (1) the battery blowup I assume was a hydrogen buildup but was that tap water related or something like a voltage regulator problem where the battery was overcharging or other?, and (2) following the battery problem and restart why could he not turn off the tractor?.......Thank you, Gary

 

[wmonroe]

Should have used demin water in the battery. When the battery let go it probably fried the fuel shutoff. I would also check other electric switches and see what else doesn't work.

 

[k0ua]

I would measure the charging voltage, I think you will find it is very high, probably around 17 volts, You regulator likely has a problem, and the alternator is running wide open. This causes the battery to boil, produce hydrogen gas and either split the case to let it out or explode. Charge voltage should not be over 14 volts. This is a simple test, just get a face shield on, and measure battery voltage at full throttle.

 

[KennyV]

k0ua is right... over charge, pushing a lot of hydrogen out of the water... tap water is going to have minerals in it that will 'eventually' screw up your battery, but in this case not a problem as the battery is Now junk anyway.
get the voltage right or it will burn up other electrical components and ruin the replacement battery... He may have Just burned up a fuse in his fuel shut off system... KennyV

 

[Haoleguy]

Thanks very much for the responses. I've relayed suggestions to test the charging system and the fuses for the fuel shut-off......Thank you, Gary

 

[skyhook]

If it was the original battery, of twelve years,,
it may have dried "naturally", not from overcharging, but he should check that anyways.
Once it blew, it would have caused a short somewhere,
he should check "all" his fuses.

 

[Cherokee140]

I would measure the charging voltage, I think you will find it is very high, probably around 17 volts, You regulator likely has a problem, and the alternator is running wide open. This causes the battery to boil, produce hydrogen gas and either split the case to let it out or explode. Charge voltage should not be over 14 volts. This is a simple test, just get a face shield on, and measure battery voltage at full throttle.

You should not have to check it at full throttle, we are talking about alternators not generators. If you have anything over 14v at half throttle you have issues.....that should be enough speed to get the alt. cranking.

 

[AStanton]

In regards to being unable to turn the motor off, I always keep a rag on board to stuff into the air intake. No air, no combustion.

 

[Haoleguy]

Received a picture back from my buddy and it shows one of the fuses was fried. He didn't make any comment to go with the pic. He's often short on words. Hopefully he checks his charging system next to make sure it's not over charging. Thanks again guys....Gary