Batteries overheating and exploding...

[VesperNoyer]

OK guys....this is probably something that has been discussed before, but I've had one battery explode and now have had a second one over heating on me....I am thinking its a voltage regulator issue, but can't seem to find one...is it built into the generator? This is a completely stock1969....also I have notices that it will idle fine while the batteries are hooked up, but rough when they are disconnected. Any recommendations on where to send the generator to have it rebuilt if that's the issue or any thoughts on what I am dealing with here?

Thanks for any and all input.

Vesper Noyer

[Blitz]

I would guess the Voltage Regulator as well.
It is Internal on the generator.
There are two different designs used for the 60 amp "alternator"
You could have either one..

Then there is the 100 amp , which is a totally different beast, and wont be discussed in this reply. ( If you have the 100 amp, the voltage regulator is external, under the top of the radiator, mounted on the body )


Questions:

Are these new and fresh batteries, or old and abused?

Are the fluid levels up properly in the batteries?

Are your GROUND WIRES properly connected, tight and CLEAN? ( Especially your chassis grounds )

If all of the above is YES, I would sure look at the regulator.

Unfortunately, I think its a non serviceable item, and is a replacement part. ( unless you find a good alternator shop that can de solder and replace diodes and resistors )

There is a circuit board, with solid state resistors, diodes, etc, mounted inside the alternator, with quick connect wires on it ( about 8 wires total that can be disconnected )

That entire circuit board will need to be replaced.

Sometimes they appear on E bay... for 30 to 60 bucks.

Also, the entire 60 amp alternator will appear there as well, for 60 to 200 bucks.

In this manual, the -34p, sections 8-1 thru 8-9 give a pretty detailed explanation of the board and testing it.

http://www.m715zone.com/vb/pages/manuals/34acrobat.pdf

On my computer screen its page 184 through page 214 and its very detailed, with schematics, testing procedures and readings expected.

Just mark all of your wires when you remove them.

I can remember for about 3 days where they go, and then... I cant. ( slow leak )


I had this happen on a '85 chevy silverado once.... the regulator went haywire after a long cross country trip.

3 miles from the house, after driving several hundred highway miles, all my lights got really bright, the interior dome light literally exploded into my girlfriends hair, every light on the truck burnt out ( dash, running, brake, and headlights )

It was a bad voltage regulator, putting out like 18+ volts on a 12 volt system.

I dont know why the engine runs rough with out the batteries connected.


Check the quality and fluid levels in the batteries, check your GROUNDS extremely well ( pull them and clean them, and tighten them )

Then go to the regulator.

This could burn the truck down, at least melt your 1000 dollar wiring harness.

Good luck and God speed

[Blitz]

Last critical question:

Do you have ANY 12 volt appliances/ accessories tapped OFF of ONE Battery?

"If so fact to" ...

Thats probably the problem...

the weak battery that you are pulling loads off of is not properly charging, and the other battery is overcharging.

Which battery exploded "if so fact to" ?
The 12 volt tap or the 24 volt non tapped battery?

[VesperNoyer]

The batteries are brand new.... I am guessing it might be a bad ground....I was thinking that the ground cable was looking really rough and was thinking of replacing both battery cables with old welding leads I have.

[VesperNoyer]

Yes as a matter of fact, I have my fuel pump coming off one battery. That's the o my 12 volt item one the truck.

[Blitz]

Grounds will get you every time.

Its amazing, how many times a wiring problem is corrected by cleaning and putting a new end on a ground and cleaning the chassis or battery post.

Good start.
cheap and easy.


The Fuel pump running off of one battery "constantly" seems like a very small load to me...

But its constant... and could be a problem.

What most guys do is get a 24 volt to 12 volt converter box that mounts on the firewall ( somewhere around 30 to 50 bucks ).

this will run your 12 volt accessories... up to the rated AMPS of the converter.

I have one on my truck.

The ONLY thing it runs is the 12 volt coil. ( Chevy 292, only 12 volt coil, everything else is 24 volts and STOCK including the starter )

I left it in there... even though I HATE electronics on a Vehicle.
I made an emergency "jumper wire" which lives above my wiper motor, just in case the electronic converter dies, and the truck wont start.
I can take the jumper wire and connect it directly to a battery and then to the coil... to get me down the road.


Your fuel pump "could" be a problem...
But honestly I kinda doubt it, enough to make a battery explode.


Its worth getting the 12 volt converter box, before yu go to the regulator, in my opinion.

If it does not fix it, you will still have a "safe" 12 volt appliance tap for anything 12 volts.



As a side note...
Let me say that...

I have a 24 volt system, except for the coil ( runs off a converter box )

At the same time....
I have a little bit of experience with 12 and 24 volt systems and alternative energy designs.

I have connected over 600 watts of SPOT/ FLOOD/ Driving and Alley lights on my truck, a 12 volt washer fluid pump, several cigarette lighter sockets for Q beams, a 12 volt backup light, a CB, another 2 way radio, Dome light(s), cargo area light, and 24 volt m-35 heater, 24 volt heater for positive air flow m-42 gas masks, and 24 volt ration heater

all of this is tapped off of 12 volt circuits, except the 24 volt stuff.

I balanced the loads equally, in relation to their use and run time.
they are all fused, and grounded to the "proper" respective grounds.
( 12 volt grounds and 24 volt grounds , ISOLATED )

I personally know how long I can run each accessory, and how to do it equally, to evenly discharge each battery as a SET.

I dont recommend trying this, unless you really think it out.
I have been doing this stuff since 1983, so I'm pretty familiar with all of the "dangers", and I still thought it out for weeks on end, and even revisit my logic occasionally to double check myself.

I have never had a problem.
I constantly check and maintain my batteries, and they are the batteries that came with the truck, dated 2010 ( Silver state" brand... not even top of the line batteries)

I check them occasionally with load testers and will put them on 4 stage TRACE chargers, to equalize them.

I think this is a bit much for most people, but I can attest that it works for me.

My fuel pump is a military external 24 volt now.

I also installed a set of 12 volt wires, ready to go next to the fuel pump, and I carry a 12 volt fuel pump with hoses and clamps already connected, should my 24 volt fuel pump fail, I can be back on the road in 15 minutes on 12 volt. ( tapped off of one battery )


In theory, yes...
Your fuel pump loading one battery can be causing a problem.

But in reality, when I can run 1000 watts of 12 volt accessories off of my 24 volt battery BANK ( equalized and load balanced ) i personally dont think that fuel pump is more than 40 % probable....

But logically, it should be considered first.

totally confused now?

Try a 24 volt to 12 volt converter and your grounds first.

No matter what, you are still ahead.

[Blitz]

Overthinking sometimes...

back to the K.I.S.S. method...

I'm sure you have already done this, but take a Meter, put it across the battery 24 volt poles... Check the alternator output.

If its like 30 volts or more... at 1800 rpm

Check the specs in the manual, and its overcharging ( ie = regulator )

note on my 12 volt system:
when I did my taps. I used both batteries , split into 12 volt circuits, with isolated grounds...
it got technical... just needed to specify, these loads i speak of on my truck, are off of two batteries... but equal loads

[brute4c]

Some of the military alternators have a screw on the side that is a cap basically that covers a smaller, fine screw that is an adjustment for the alternators output...you turn it one way to lower and the other to raise the voltage out to the batteries. The screw is VERY sensitive so if you need to adjust it, a little goes a long way.

Put a voltmeter on the batteries and you should read 28.8 volts fully charged...that is what the alternator should be putting out as well...check the alternator wire #5, thats the large wire from the alternator to the foot starter switch. You should have 28.8 volts there...if not, and your truck has the adjustable output, try to adjust it to 28.8...if you cant, think bad alternator.



On the 12 volt accessories on a 24 volt system...I did this for a while...I kept getting one dead battery about once a year...you can picture it like this basically:

The 2 batteries are kind of like water tanks...if fully charged, picture them both full....
Draw in 24 volts of both batteries evenly and the 2 are at the same level...alternator charges both evenly back to full.

If you draw 12 volts off one and 24 volts off both, then the one with the added 12 volt draw has a lower level than the other...now the alternator will either fill both batteries evenly till one is full and that will leave one undercharged, the 12 volt draw amount...
OR
The alternator will charge both batteries evenly until the lower level battery is full...this will overcharge the battery that did not have the 12 volt draw.

First scenario leaves a battery low and susceptible to going bad like a dead battery...that was my experience.

Second scenario leaves one battery overcharged over and over and could lead to the explosion.

Either way, a 24 to 12 volt converter is a great cure...the other way to fix this is to mount a 2nd alternator in 12 volts and run a single battery in 12 volt...this does complicate things but it cures the problem...

[Von]

These are great:

http://www.amazon.com/dp/B00BWKXTUU/..._new_dp_review

I'm ordering another one today.

[brute4c]

20 amp is a great size...I ran a civilian ignition, windshield washer, civilian heater, tcase temp gauge and digital fuel gauge off 12 volts on a 20 amp unit.