VH Battery overheating (boiling!)

[bajab]

I have an 'interesting' problem that I need some help with please.

My 1983 VH commodore wagon regularly overheats the battery, to the point of steam gushing out of it!

My paint work is ruined, the area around the battery is constantly covered in white "dried acid", I barely get a year out of new batteries (which have to constantly re-filled), and the smell really gets to me sometimes (and cannot be healthy).

This problem usually occurs on long runs (over 40 minutes).

Over the years I have had FIVE different alternators in this car, of varying types and sizes, and installed by different mechanics from different shops who all assured me that was the problem (ie alternator was faulty in each case). Obviously they were wrong, but nobody seems to have any idea what could be causing it. After replacing the alternator, the problem goes away for a while (months at a time), but eventually comes back.

I am not a mechanic and do not know that much about cars in general, but would very much like to get this problem fixed rather than getting rid of the car.

Any ideas or useful suggestions (that do not include a large bonfire) greatly appreciated.

[JD]

could be electrical shorting, either in the battery connections or the wiring of the car

[SL/ENUT]

Its either that above or could be the earth points/earth wires.

[fatboy2869]

I would say it might be a combo of both those problems try relocating the earth point

[bajab]

Thanks for the fast replies.

Is there anyway I can test this, or something else that might show up if it is one of the above?

[Not_An_Abba_Fan]

Fit a larger core earth strap from the head to the body and from the neg battery terminal to the body then check your voltage at the alternator. Sounds like it is frying the regulator. How many accessories have you got? Do you have a big thumping bowel emptying amp and sub in your car?

[bajab]

Basically no accessories, except for a little plug in torch and a basic CD player (3 years old). No amps, subs, or gadgets of any kind.

I am guessing I will have to replace the regulator then?

[Not_An_Abba_Fan]

The alternator has a built in reg but it is replacable. What voltage is your alt putting out if you know?

[JD]

get a multimeter of some kind, they are invaluable

[immortality]

also check the main wire from the alternator to the battery positive terminal, bad connections can cause resistance. i've had a alternator putting out over 16 volts when my main lead failed at the battery connection on my old VK

[robbo10]

I know it's a bit late now but is the battery big enough (550 cca. or bigger). Is the Alternator a high output one. If you've got a really big alternator pumping out lot's of juice and the regulator is dodgy, and only a little battery to catch it in, the battery is going to get real excited.

[bajab]

I have not checked the output of the alternator yet (since I thinki it is a gievn that the regulator is shot), but found out that a larger strap from the head to the battery and alternator to the battery have already been used (green ones).

The current alternator and battery were supposed to be bigger than required too - another effort to try and 'fix' the problem.

As yet, I have been unable to find a strap from the engine to the body, and the strap from the battery to the body appears to be quite smaller (thin black one).

The plan is to get the alternator replaced (yet again) and have the small cable replaced with a large one, but I have very little faith in this fixing the problem.

If anybody hears of somebody else having this problem and fixing it, please let me know.

Thank you all for your advice and suggestions.

[SoulGrind]

Sounds like hydrogen gas to me. It's either because of strong charging or discharging. Either get a bigger rated battery or a smaller alternator.

[robbo10]

This time keep the receipt for the work done and if it doesn't get fixed and stay fixed. Keep taking it back until it is. A good Auto Elec. should be able to take a good look and tell you exactly what needs to be done. If the person fixing it is at all doubtful or says that they are just going to try something. They normally don't know what's wrong, are just guessing, and will keep guessing until they fluke it. The good ones are honest, and up front. Remember, "Do it right, do it once.".

[bajab]

Ok, so one year down the track, and I am having problems again, although slightly different.

Now the starter won't crank after resting for five minutes after a long drive. Turn the key and nothing - dead silence. I've read in other posts here that it could once again be a power problem - that the starter needs more power when it is hot and may not be getting enough from the battery.

So I've been putting the battery charger on each night to make sure the battery is at full power, and the problem still occurs (btw - should it always need charging? I've never connected it and had the green light come on before an hour or two of charging).

I've tried cleaning the terminals etc but no change (then again, I've probably not done that good a job).

Only thing I have found is pouring a couple of litres of water over it cuts down the wait time dramatically.

Any suggestions or ideas? Is this possibly related to the problem causing the boiling battery previously?

[Drewie]

I have the same problem with our 202 VC, I am 99% sure it is the starter motor itself that is giving trouble, I can start ours and it runs fine, go for a 10 minute drive and turn it off then won't start, nothing completely dead, until it cools down.
A few tests you can try like I did will confirm it is the starter motor that needs replacing. First when it will not crank get a test light and with someone turning the key see if there is power at the solenoid on the starter,
pull off the small push on wire and connect your test light from earth and the other end push into the wire you have pulled off, if the test light lights up when the key is turned on then you have power at the starter.
Also another thing you can try when it is in the dead no start mode is run a wire direct from the battery to the terminal on the solenoid the one you pulled the small wire off, if it still won't crank even with direct power from the battery it is most probably the starter its self. Also make sure the big bolt on connection on the starter is clean and tight. I have priced a few from auto electrians and general feeling seems to be it is better to get a new one than repair the old one, most wanted around the $150 to $180 for a newie or not much cheaper if they could repair the old one, wreckers wanted about $45 for a used one, but you might end up with the same problem, I am not looking forward to pulling mine out as it has extractors and looks a prick to get to.

[Cane_It]

voltage drop to the starter motor would be the problem there,

fit a relay in the starter circuit, connect the purple wire that goes to the solenoid to the trigger side of the relay and then run a reasonably heavy wire from the battery to the relay and then out to the starter solenoid where you disconnected the existing purple wire from. That should fix your problem.

Also check that the two screws that hold the plastic cap of the starter solenoid on havent come loose. disconnect the battery before getting in there with a screwdriver though...

[bajab]

I am not looking forward to pulling mine out as it has extractors and looks a prick to get to.

Tell me about it! I think the closeness of all those stinking hot pipes causes problems like this.

fit a relay in the starter circuit,

Not being a sparky, I have no idea what sort of a relay to fit. What do I need to ask for at the counter please?

connect the purple wire that goes to the solenoid to the trigger

No puprle wire. Think the heat from the extractors have made them all black. Is there a different way to identify the wire?

disconnect the battery before getting in there with a screwdriver though...

Figured this one out the hard way.

I read a similar answer in a few of the other threads of people having trouble with starting, but I am unsure if it is related to my boiling battery problem at all. Is this just something that happens in older cars, a design fault, or what?

[bajab]

BTW - I forgot to mention the new alternator (the one I put in after last posting to thris thread) is now putting out 14V. How can the battery always take a charge (from the mains charger) if the alternator is oversupplying, and why is the alternator again apparently on it's way out?