# Hissing Leisure Battery



## florenceoccupation (Apr 24, 2011)

Have just used our motorhome for the first time this year, and after having to renew the starter battery (our fault entirely!), I have noticed a hissing noise coming from the leisure battery.

We have been on electric hook-up this weekend and should probably test the MH for a couple of days without hook-up, but a little alarmed at the sound to try that. We have had the van for 3 years (its now 6 years old) and have never noticed this noise before.

Any advice would be appreciated as my husband thinks I'm just being neurotic.

Anita


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## Jezport (Jun 19, 2008)

On a new battery you may hear a slight bubbling noise when on charge. I was concerned about mine but Udo Lang at Schaudt informrd me it is normal.


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## DTPCHEMICALS (Jul 24, 2006)

Is your battery called Syd 8) 
dave p

It will be ok in the morning I am sure. Ours did the same.


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## CliveMott (Mar 10, 2008)

Check the battery voltage on charge using an independant voltmeter. If it stabilises out at much more than 14 and you are overcharging. This will cause gassing and loss of electrolyte.
C.


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## BillCreer (Jan 23, 2010)

An easy test, if you haven't got a voltmeter, is to feel if the casing is hot when it is hissing. If it is then it's possible that a cell has died and the voltage can't get up to a level where it can tell the charger to switch off. It'll boil your acid away.


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## DABurleigh (May 9, 2005)

Multimeter highly desirable. Without it, then hissing MAY be bad; bubbling definitely so.

Dave


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## BillCreer (Jan 23, 2010)

DABurleigh said:


> Multimeter highly desirable. Without it, then hissing MAY be bad; bubbling definitely so.
> 
> Dave


Dave,
I would be worried if my Gel batteries bubbled but I think it is quite normal for it to happen in Lead Acid when they are being charged.
It's the hydrogen (that needs venting) being produced during elecrtrolysis.


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## DABurleigh (May 9, 2005)

A matter of definition  Strictly you can't get hissing without bubbling - I was meaning bubbling as verging on what some people call "boiling".

Dave


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