What would cause a battery to bubble and fizz then explode?!

[Djw Dave]

As above.

Battery last night was fizzing which we thought was odd but maybe was just hot cos car had got hot.

To be on the safe side I cleaned up 4 earths in the engine bay this morning, fitted a new battery and after a very short run its fizzing again. Obviously disconnected it now but need to know whats causing it as a battery every day would be an expensive habit!

Cheers
Dave

 

[thejoose]

Was it fizzing right away or did it start fizzing after a while of the engine being on

If it was fizzing without the engine being on it sounds like you have a big short (a big short because a small one would probably have burnt out)

If it was fizzing after the engine being on for a while its possible the regulator on your alt is dead and it was charging the battery at a higher voltage than it liked

 

[MrMark]

Overcharging?

 

[Djw John]

Only once its been on.

So new alternater the only cure?

Cheers btw

 

[thejoose]

Only once its been on.

So new alternater the only cure?

Cheers btw

Get A multimeter and check the voltage across the battery with the engine running

anything above 14.4v would mean a new regulator (depending on how easy it is to get at your alt you might want to replace the whole thing)

how old is the car?

 

[Djw John]

Its an engine conversion mate. Engine is from a 95 Valver with 103k on it.

Wonder how easy the regulater is to do!

 

[Dink]

sounds like the regulator to me

not sure if it's an easy job tbh i'd just get another one or get it done by a pro

 

[Djw Dave]

Well its defo overcharging, fine at idle but up to 18v pretty quickly, 3k or so.

We noticed that the bottom bolt was half out and that it was off alignment, could this have caused it? Would putting it back in properly fix it or will it be goosed now and better to get a new one?

Cheers all btw

 

[SBV116]

New one mate is the best bet by far!!!

 

[Djw Dave]

Yeah was thinking that! Cheers bud

 

[SBV116]

You don't want the battery to blow up either! It's fecking messy!

 

[ditz]

especially not in your face, it hurts lol.

 

[Djw John]

You don't want the battery to blow up either! It's fecking messy!

Yeah does appear to be, smells pretty bad as well

 

[thejoose]

Alot of alts use the connection to the engine block as the earth - also the regulators use that connection as a register to determine a voltage drop, this voltage drop determines the output of the regulator, if the connection to the engine block was a bit shwonky this could cause the regulator to go haywire.

fix the alt connection to the eingine block then retest - see if thats sorted it, if it has your lucky, if not then it new alt time

 

[Djw Dave]

Alot of alts use the connection to the engine block as the earth - also the regulators use that connection as a register to determine a voltage drop, this voltage drop determines the output of the regulator, if the connection to the engine block was a bit shwonky this could cause the regulator to go haywire.

fix the alt connection to the eingine block then retest - see if thats sorted it, if it has your lucky, if not then it new alt time

Sorry not really understanding what earth it is mate. Pics?

 

[Djw Dave]

Also when i removed my alternator last night there was only 2 connections on it.

One onto a post teminal (a thickish black wire with ring terminal)

And a multiplug with 2 wires in it. Its a brown plug.

There is another post terminal on the alternator but seems to have nothing attached. I have looked over the wiring and cant find anything to connect. Is that right?

I have rechecked all the earths. one from box to the body, one from the neg terminal to the slam panel and anther that goes onto the reas top of the gearbox. All getting decent earths. Is there any other ones i may ha ve missed?

New alt is in place, just needs a few bolts put in to finish, but i want to make sure im not going to damage the new alt if there is somthing silly i have missed.

 

[Djw Dave]

New alt fitted. Will test run and update

 

[Djw Dave]

WOW! Fast!

Love it!

Working!

Top nobbing!

 

[SBV116]

Result!

 

[Djw Dave]

Result!

Indeed!!! So chuffed. Got new downpipe to fit and powersteering leak to sort.