Fizzing battery?

[ChrisCurvyS]

I'll spare you all the tedious details but I've had a mystery electrical gremlin with the bike which keeps leaving me with a flat battery.

It doesn't seem to be the battery (replaced that), doesn't seem to be the reg/rec (replaced that) and doesn't seem to be the circuit (RAC checked that and said it was fine) - I've also had the panels off to check the wiring, and couldn't see anything amiss there. Could be the alarm or Scottoiler methinks, although both seem to be working fine.

Anyway, reason I'm here - I put the flat battery on a trickle charger the other day and after a couple of hours, it got very warm and started making a slight hissing/fizzing sound. It also didn't seem to be charging as quickly as it had done previously - does that mean it's knackered?

Ironically, I rigged up the old battery to the charger and it seems to have charged up fine and be holding 14 volts no problem, with not a sound to be heard. It's been flat in the shed for months - will be trying it on the bike tomorrow.

[flymo]

are the fluid levels correct in each of the battery cells? When its charging, what voltage are you getting across the battery terminals?

And on the bike, when its running at idle, what voltage are you getting at the battery terminals?

Also, disconnect the negative lead from the battery and check current drain with a multimeter.

[NTECUK]

Is this a bike or car trickle charger.
Car one will soon kill a bikes battery

[ChrisCurvyS]

Cheers mate - bit of a confession though. I don't own a multimeter or any other electrical testing equipment! Completely hopeless with electrics full stop - makes my head hurt.

However, during one of my many breakdowns, (outside work in Liverpool as it happens) the RAC chap ran tests at all the points you mention and said everything with the circuit seemed to be fine. He suspected it was the battery, but when I took that back to J&S (who've always seemed pretty trustworthy in the past) they tested it on their machine and said there was no fault.

I've not checked the fluids inside it TBH - all levels were fine when I first put it in and not seen any evidence of leakage, so that never crossed my mind. Will check tonight if it's worth doing though.

As I said, the backstory to this is a long and tedious one - I just wanted to check that a fizzing battery while charging isn't normal!

[flymo]

The reason I ask is that, for whatever reason, if the battery is getting too high a charge voltage then it will boil off the fluid.

Pop into my place if you fancy a cuppa, we can take a look.

[ChrisCurvyS]

Cheers mate - sent a PM.