Battery, Alternator, something else???

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mcpotters
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Battery, Alternator, something else???

Post by mcpotters » Sun Jul 16, 2017 6:21 pm

This is long one as it has stumped us.
We bought Bruce (N reg, 2L diesel) about 3 years ago and we have had to change the starter battery twice in that time (and leisure battery 3 times - but that could have been poor maintenance on our part)
We haven't had many problems recently and we took him for a good run (all afternoon) came home and went to move him a week after and completely dead. The central locking wasn't even working. The only thing we can think of that may have drained was a) the radio was in but not on b) there was a USB port plugged in but not connected to anything...otherwise stumped.
Van was then jumpstarted, moved and turned off. The battery removed and gave a reading of 11.07v then charged it up for over 24hrs and checked again it then read 11.03v.
Put it battery back in van and jumpstarted.
Reading was then checked and showed 12.2v
Engine revved to 2000rpm and voltage was 13.2v
Then fluctuated the revs and voltage readings fluctuated accordingly.
Turned on lights and heater and voltage dropped
Engine turned off and voltage was now 12.1

So any ideas? There was no indication to show faulty alternator as no warning lights, no electric problems, etc.

And can a battery go completely dead to 11.07v after a jumpstart?! Weird

We have noticed a very slight bulge in battery. Did think that alternator was powering too much but doesn't seem it? Alternator looks fine and belts are tight and seem ok.

It's heading to a garage tomorrow - but do you wonderful folk gave any ideas?
Thank you
Bob
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Re: Battery, Alternator, something else???

Post by Bob » Sun Jul 16, 2017 6:32 pm

Hi, and welcome. 8)

If the battery has a bulge remove it very carefully and dispose of it. Wear eye protection and gloves, ideally an apron, too.

Personaly I wouldn't try and start it until the battery was replaced.

Hopefully Geoff will give some technical input, and If it's diesel it will be 2.5 ltrs, typo. :)


I'm sure this can be sorted fairly easily.
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Northern Bongolow
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Re: Battery, Alternator, something else???

Post by Northern Bongolow » Sun Jul 16, 2017 6:37 pm

has the usb port got an on/off switch, all the good ones do have as it will be drawing power without anything connected to it if it hasnt got one.
mcpotters
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Re: Battery, Alternator, something else???

Post by mcpotters » Sun Jul 16, 2017 7:09 pm

Ooh I don't think so. It has a blue light to show it's on but its not illuminated when engine is off. We're usually pretty good at removing/turning off anything we can but this time forgot :(
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g8dhe
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Re: Battery, Alternator, something else???

Post by g8dhe » Sun Jul 16, 2017 8:35 pm

The battery voltages are ALL on the very low side, which would point towards low output from the alternator, or bad connections to the battery terminals. It might be worthwhile getting an automotive electrician to look it over as that's a lot of batteries to get thru in the time given!
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cmm303
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Re: Battery, Alternator, something else???

Post by cmm303 » Sun Jul 16, 2017 11:08 pm

Allowing a battery to completely drain really shortens its life. If this is happening then it could explain your consumption of batteries.

Is your Bongo left unused during winter?
Chris with BertieB
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rita
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Re: Battery, Alternator, something else???

Post by rita » Mon Jul 17, 2017 8:48 am

mcpotters, Five batteries in Three years, just out of curiosity did you purchase New batteries with a Guarantee or did you use second hand batteries.?

Most decent batteries carry a 2/3/4 or even 5 year warranty.

Good Luck.
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Re: Battery, Alternator, something else???

Post by rita » Sun Jul 23, 2017 5:51 pm

Silence Is Golden.

:lol: :lol:
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