It's funny how a query raised in one thread can lead you to check something on your own van only to find a problem that at first sight appears to be easily rectified and then ends up taking two whole days to put right.

Someone asked recently about venting a lead acid battery and the Forum's resident expert JohnE referred to a battery vent tube that should be fitted. So I checked our caravan to confirm that it has never had one. Simple, buy a tube, drill a hole through caravan floor, fit tube, job done - easy, innit. If only!

First of all, look at this:

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Clearly at some time in the past, battery acid has spilled under the seat and damaged the wheel arch cover trim. You can see the extent of the acid soaked woodwork.

Then I checked the acid-stained warm air ducting only to have it fall apart in my hands in two places.

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The battery hold down strap was a funny colour so I removed the battery only to find that the wooden frame in which the battery sits had also been soaked - so out it came. It was a bit of a mess and would have to be replaced.

So, while I'm waiting for the vent pipe to arrive (I ordered one from eBay which is a bit cheaper at £2.79 inc p&p and a bit longer than the one JohnE linked to, I put my thinking cap on and decided it was a two-pipe problem.

In the end, rather than trying to replace the whole cover which was complicated and would have involved extensive dismantling, I decided to re-cover the cover, if you see what I mean?

To repair the warm air ducting I cut out the corroded portion of the major damage to give flat ends and re-joined it by wrapping a piece of thick aluminium foil cut from a roasting tray around it all held in place by a liberal application of insulating tape (I didn't have any duct tape handy). For the less damaged part I did the same but without cutting the pipe.

I made a cardboard template and then cut a piece of hardboard to cover the vertical face which I glued in place using Evostik. Fitting the curved upper part was much more difficult as hardboard is really too thick for the job and is hard to bend. Soaking it in water worked but, with hindsight, a better material would have been the thin board that forms drawer bottoms in flat-pack furniture. After crumbling out all the acid-rotted original hardboard, I managed with difficulty to insert the edge of the new board into the seal against the outer wall of the caravan and fixed it in place with staples, as was the original.

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I think it looks pretty good.

Here's the plywood battery locator, note how the plywood has de-laminated:

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I washed out the battery retaining strap, which thankfully was undamaged, in warm soapy water and while I was waiting for it to dry, I cut a new battery locator from a piece of MDF that I had lying around and fitted it using new screws.

Lead-acid batteries come with two plugged vent holes and the instructions say to remove these before use. If you are fitting a vent pipe you need to leave the other vent plugged. As I didn't have a plug I looked around for an alternative and found that on my Bosch battery a shortened plastic number plate bolt was a perfect push-fit.

And here's everything put back together and looking ship-shape and Bristol fashion.

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All that remains is to fit the vent pipe when it arrives but that's a simple job (famous last words?) and access is good.

At first I was mystified as to why or when we had had such a catastrophic acid leak inside our caravan. There are two possibilities, when the BIP failed for the second time and was delivering 17 volts to the battery and two years ago in France when the battery failed and I had to replace it with an ordinary car (as opposed to leisure) battery at the horrendous price of €140, twice what I would have paid in the UK for the same unit.

Ah well, it could have been worse. but if you have an older van (ours is a 2003 Triton) it might be a good idea to have a look under your seat and just check that yours does have a vent fitted and that all is hunky dory.

Looks like a job well done
I'm sitting on mine at the moment so will look later
Randa

Just an update re the breather pipe which I fitted yesterday. The job is done but it wasn't quite as simple as I'd anticipated.

I measured the distance from the internal wall and the distance to the rear of the window edge very carefully twice and then checked underneath to ensure that I'd missed the chassis member. Bugger, I was right above it and as there were power cables to the motor mover adjacent I drilled a tiny pilot hole through the floor a bit further from the battery than anticipated, left the drill in the hole and got back underneath to check it was clear before enlarging it to 10mm for the outlet pipe.

Here's the finished job. 'X' marks the spot where the hole was originally supposed to go.

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