Main battery keeps dying

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dansk
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Main battery keeps dying

Post by dansk »

We've always had an issue with our main battery dying, especially after a heavy nights rain, but this was never a major issue with our original diesel engine. We have have since replaced it with 2.0 petrol engine and now its more like a one in three chance that we wake up and need a jumpstart, rain or not. I don't remember the figure but a mechanic neighbour tested both our batteries and said they checked out. I'm not sure if its an issue with the battery draining out, as when we do need a jump it catches straight away (although having said that, the radiator fan is loud now and a little bit of city driving on a nice summer day, and the fan will be buzzing away for sometimes 20 minutes afterwards.. ).

Does this sound like just a problem with a poor quality battery? The other day i had to get the AA to come and jump us, and he pointed out that our main battery is Halfords own brand and how "pooh" they were. Banner has been recommended but before splashing out I wondered what general opinion on best starter battery might be - or is it more likely there is a drain somewhere I could track down or that the battery is a just a little too exposed to the elements and maybe adding some protection underneath to stop water splashing up..?

The advice on the wiki is a good laugh https://club8090.co.uk/wiki/Pe ... flow_chart but I can confirm we often hear bit of a click when it won;t start and the bat light and even the radio will all work ok. The new engine fit is brand new and the starter plugs all look nice and tight and clean :)
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MidLifeCrisis
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Re: Main battery keeps dying

Post by MidLifeCrisis »

It's probably both - you probably have a drain on your battery, but the many times that you have flattened it have probably done it some damage!!

Do you have a multimeter that can measure current?
If you do, pull out all the fuses in your fusebox; connect the multimeter (in current mode) between the battery negative terminal and the battery negative terminal cable; the current should read as zero (because you have pulled all the fuses out); now add the fuses one by one until you find the one that causes a jump in the current - that is then the circuit that you'll have to investigate in more depth to find the culprit!!
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a1winchester
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Re: Main battery keeps dying

Post by a1winchester »

As an interim measure until you have discovered where the fault is, might I suggest fitting a battery isolator?
http://www.ebay.co.uk/itm/Battery-Isola ... 3cf59ea70f
I had a similar mystery battery drain problem, which always seemed to let me down at the most inconvenient times.
Now, since fitting one of these, I always isolate the battery if I am parked for any length of time, and avoided a lot of grief.
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dansk
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Re: Main battery keeps dying

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I don't have a multimeter but have wanting to get one for a while.. (any recommendations? - ideally something that I could use on both a car bat or a computer board ). And that isolator switch idea is a good one - thanks! I'm thinking maybe I should get both and do a bit of testing before splashing out on a new battery. Although.. since the van was essentially out of action for almost a year the current battery has probably suffered enough and I should just replace it either way.

I'm going to sound like a total eejit asking this but when we have the leisure battery on - does it also take on the power for the dash board stuff - radio, cigarette lighter etc or do these still draw on the main bat? I assumed the later - totally separate circuits right?
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a1winchester
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Re: Main battery keeps dying

Post by a1winchester »

dansk wrote:I don't have a multimeter but have wanting to get one for a while.. (any recommendations? - ideally something that I could use on both a car bat or a computer board ). And that isolator switch idea is a good one - thanks! I'm thinking maybe I should get both and do a bit of testing before splashing out on a new battery. Although.. since the van was essentially out of action for almost a year the current battery has probably suffered enough and I should just replace it either way.

I'm going to sound like a total eejit asking this but when we have the leisure battery on - does it also take on the power for the dash board stuff - radio, cigarette lighter etc or do these still draw on the main bat? I assumed the later - totally separate circuits right?

My multimeter - looks like it could be used on circuit boards - http://www.amazon.co.uk/gp/product/B000 ... ge_o02_s00
Also got one of these as I wasn't certain if I had a duff battery at the time - http://www.amazon.co.uk/gp/product/B000 ... ge_o04_s00
Unless you have had some fancy wiring in your van, I wouldn't expect the dash electrics to be fed by the leisure battery. They can and will drain the starter battery. If you need extra electical 12V supply, get a power pack. They often have a cig lighter socket, and so you can insert a usb adapter, as well as being extra insurance afainst a flat starter battery.
http://www.amazon.co.uk/gp/product/B004 ... ge_o05_s00
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dansk
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Re: Main battery keeps dying

Post by dansk »

Thanks for clarification. And I do like the look of those meters - they got a steampunk look about them!

I actually just got back from maplins and picked up a UNI-T ut30 multimeter on the assistants rec - so I will begin going through all the fuses soon. Also bought the Maplins Digital Jump Starter - which actually failed to jump start the van. This might be because it wasn't fully charged or I was just not doing it right. The instructions called for clipping the neg clamp onto a non-moving part of the engine - I was contemplating just directly hooking it up like a normal jumpstart but before I risked it, I ended up getting a normal jump from a BMW. Again, started straight away so i really dont think its owt to do with the battery running down.

A thought - the connectors to the starter battery do look a little old & dirty - how safe is it to clean them - wd40 or is that just crazy talk?
t25 hi-top komet [89/90]
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a1winchester
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Re: Main battery keeps dying

Post by a1winchester »

WD40 is probably not a good idea.
Disconnect the battery, then clean the terminals and clamps with wire brush / emery cloth / wire wool. Clean em up with a rag, then apply a smear of vaseline to the terminals to reduce the risk of corrosion in the future.
Take care not to short the terminals if you are using any metal tools. Beat to cover the one you are not working on.
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Re: Main battery keeps dying

Post by greasemonkey »

a1winchester wrote: Clean em up with a rag, then apply a smear of vaseline to the terminals

You probably know this, but just in case it isn't clear to anyone reading, the vaseline goes on last, to protect to overall connection.

Vaseline is an insulator, so mustn't go between connections, only on the final connection to block out oxygen and moisture :)

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dansk
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Re: Main battery keeps dying

Post by dansk »

Brilliant..good to know..as if even if I but a new battery I have plans to make use of the old one ☺

I am almost def certain it's the rad fan is the culprit. I got a normal jumps tart yesterday. . Drove around for an hour. Parked up and all good. Then over an hour later I hear rad fan kick in, I go to check the engine and whacha know it wont start. I hadn't turned anything else on..not even the radio. I connected a jump pack to the bat and while it couldn't start the car it gave it enough juice to immediately turn the fan back on.

I read about chicken switches. .sounds perfect if I could disable the fan when it's parked. But while I figure that out is there an easy way to disconnect the fan switch..just temp so I can charge bat and get it home!
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marlinowner
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Re: Main battery keeps dying

Post by marlinowner »

Fuse 1 (leftmost) is for the radiator fan, pull it out and fan should stop.
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Re: Main battery keeps dying

Post by ash005 »

I have a komet and a similar issue, drove to lakes Sunday, wouldn't start this morning !
Been an issue every time it's used, I'll check fuses at the weekend
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Re: Main battery keeps dying

Post by waltraud »

Rad fan connector that switches fan on is located behind the lower plastic trim at the front. It might be worth checking
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dansk
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Re: Main battery keeps dying

Post by dansk »

marlinowner wrote:Fuse 1 (leftmost) is for the radiator fan, pull it out and fan should stop.

Thank you so much marlinowner! I know its just a temp fix but is a bloody good fix - I just have to pop out fuse one (which i note has the largest amp rating) when we are parked up and no more battery issue. I can't really see any danger in not having the rad fan come on when the engine is off surely...
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dansk
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Re: Main battery keeps dying

Post by dansk »

waltraud wrote:Rad fan connector that switches fan on is located behind the lower plastic trim at the front. It might be worth checking

Cool - thanks :) Any idea what I should be checking for? Can I do something with the existing switch to make it less sensitive - or add a second switch so I can disable it when the engine is off? Or should I maybe be shop around for a replacement?
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Re: Main battery keeps dying

Post by MidLifeCrisis »

If the fan is randomly turning on then it's most probably a duff radiator fan temp switch - I'd just replace it (they are cheap!)
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