Battery Boiling Over

[Cdawg]

I have a 2000 TC 40d. This will be the second time that I have had to scrape all the rust from under the battery because it is boiling over. Last time I had to replace the radiator as well. Thinking it was a problem with the alternator I brought it in to be tested at a reputable shop. The alternator tested out fine. I think the problem is that it is putting out 14.6 volts. At any RPM. So yes it is regulating but is that too high a voltage. I have let it run for quite some time and the alternator started at 6.7 amps and now is down to 5.7 amps. Does anyone know what voltage/amperage a battery needs to get to before it boils over?

 

[rekees4300]

If the voltage regulator is defective it could be causing the alternator to overcharge the battery and that will cause the battery to boil over.

 

[Eagleview]

I have a 2000 TC 40d. This will be the second time that I have had to scrape all the rust from under the battery because it is boiling over. Last time I had to replace the radiator as well. Thinking it was a problem with the alternator I brought it in to be tested at a reputable shop. The alternator tested out fine.

Are you sure the voltage regulator is in the alternator ? It could have an external regulator that is faulty . If this is the case , the alternator could test fine but the external regulator would be at fault and untested . Either way , it is a regulation problem .

Less likely but still possible is that there is a buildup of deposits in the bottom of the battery shorting the plates , this can turn a battery into a 12 volt kettle .

 

[JC-jetro]

I have a 2000 TC 40d. This will be the second time that I have had to scrape all the rust from under the battery because it is boiling over. Last time I had to replace the radiator as well. Thinking it was a problem with the alternator I brought it in to be tested at a reputable shop. The alternator tested out fine. I think the problem is that it is putting out 14.6 volts. At any RPM. So yes it is regulating but is that too high a voltage. I have let it run for quite some time and the alternator started at 6.7 amps and now is down to 5.7 amps. Does anyone know what voltage/amperage a battery needs to get to before it boils over?

Why don't don't you put a voltmeter on your battery leads while the engine running and gear in Neutral. Rev the engine up and down, voltage will go up and down as well. I think the charging voltage should not exceed 14.8 volt. Let's see what you get and report back, most likely it is voltage regulator. I don't know on newer tractors if the regulator is solid state and in the alternator (internal) but on my older vintage tractor is external.

JC,

 

[jinman]

Fix your rust/corrosion problems with your tractor first and then buy an Optima Red-top starting battery and your problems will be over. The Optima is not a direct replacement for your OEM battery, but you can modify your tractor to accept it. I put a battery box in my tractor. I've had the optima for over 5 years and no problems with leaking, starting, or rust/corrosion. You'll pay twice as much for an Optima, but you won't regret it.

 

[dqdave1]

Listen to JInman; I second his advise. I also installed an Optima about 7 years ago, and no problems.

 

[Cdawg]

Are you sure the voltage regulator is in the alternator ? It could have an external regulator that is faulty . If this is the case , the alternator could test fine but the external regulator would be at fault and untested . Either way , it is a regulation problem .

Less likely but still possible is that there is a buildup of deposits in the bottom of the battery shorting the plates , this can turn a battery into a 12 volt kettle .

I am sure that the regulator is in the alternator. I got a schematic from the dealer. I don't have the specs though so don't know what the float charge should be. Typical float charge in marine engines is around 13.8 volts.

Why don't don't you put a voltmeter on your battery leads while the engine running and gear in Neutral. Rev the engine up and down, voltage will go up and down as well. I think the charging voltage should not exceed 14.8 volt. Let's see what you get and report back, most likely it is voltage regulator. I don't know on newer tractors if the regulator is solid state and in the alternator (internal) but on my older vintage tractor is external.

JC,

Did that JC. It doesn't vary much it is at 14.5 v. The amperage has come down to 4.3 amps but that is still alot of amps for a brand new battery at full charge. The regulator is internal.

Fix your rust/corrosion problems with your tractor first and then buy an Optima Red-top starting battery and your problems will be over. The Optima is not a direct replacement for your OEM battery, but you can modify your tractor to accept it. I put a battery box in my tractor. I've had the optima for over 5 years and no problems with leaking, starting, or rust/corrosion. You'll pay twice as much for an Optima, but you won't regret it.

I thought of that Jinman but gagged when I saw the price. They were $175. Might have been cheaper in the long run. May be I'll go back to the parts store and see if they won't do a trade for me. The battery I have lasted four years.

I am also thinking of getting rid of the internal regulator and adding my own external regulator. I'll have to study up on it a little.

 

[Eagleview]

Just thought of another tricky one that I had to figure out , the rectifier was faulty and was giving the battery a belt of AC current every now and then . That made the battery boil . Don't discount this possibility when fault finding .

 

[Redneck in training]

Make sure that your voltmeter is working right. Old analog meters can be quite off.

 

[JC-jetro]

I have changed diode-trio (rectifier bridge) on my GM car and few other friends' cars but can not remember once if it caused battery boil over. I bought a battery tester from JCPenny when I was in college. I still got it and not only it shows under or over charge, it could also show bad diode. I wondered if you had a couple of shorted cell in your battery, can it cause the boil over. I'd be taking a battery off of one of my vehicle and put it on the tractor, I then compare and contrast voltage and amp read out with the existing battery. That might shed some light.

JC,