Adria Twin Water tank leak

[Mike Ferguson]

Hello,
My first post as I would like some advice.
Having considered buying a motorhome for many years I am now the proud owner of my first van - a 2008 Adria Twin.
It has a fresh water tank mounted under the dinette seats.
The tank is held in place by 2 straps.
It looks as though those straps have worked loose and the tank has moved about a bit causing stress in the area around the drain pipe.
The tank is now leaking from a small crack where the drain pipe joins the main tank.
I have removed the tank from the van.
Has anyone any suggestions as to what I can do to effectively repair this?
I don't know whether anyone else has had the same problem.
I have emailed Adria to enquire about a new tank but it is likely to be quite expensive.
I’m wondering whether I can cut the drain pipe off and then widen the hole slightly to eradicate the stress crack.
I would then be left with a hole about 28-30mm in the bottom of the tank.
Are there suitable fittings that I could then use to reinstate some sort of drain pipe?
Any suggestions would be very welcome,
Thanks for your help.
Mike

 

[Figaro]

I'm sure a DIY repair is possible.
How about cleaning it up with sandpaper heating it with a soldering iron to melt the plastic over crack and then a liberal coating of araldite.
Good stuff and it might work
PS make sure it's not stressed when refitted

 

[Mike Ferguson]

Figaro -
Many thanks for your suggestion.
I’ve used Araldite many times in the past and it usually makes a very strong repair.
I thought about mixing up a large dollop and applying it around the pipe on the outside of the tank in order to stop the leak and really reinforce the area.
The trouble is Araldite claims to be compatable with “most plastics except polyethylene, polypropylene and teflon”. I think the tank is made of polyethylene.
When I do eventually refit the tank I will make sure its held in place more
securely than with the 2 thin straps that Adria use.

 

[Richard n Ann]

What about a tank overflow fitting? Then just plug or glue some 21.5mm overflow pipe in

 

[Figaro]

Didn't know that compatibility issue.
Maybe try mixing a bit and putting on outside of tank, see if it sticks ?
Or maybe Google for other compatible adjesives

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[Mike Ferguson]

Richard and Ann - love your suggestion.
Have gone and searched google. If I could get one like this perhaps I could add a tap or valve of some sort under the van to drain the tank?

 

[Ridgeway]

Assuming you can access the inside with your hands then a bulkhead might be the best solution. Silicone with some 5mm perspex type material (PE or PU) would work well and i've sealed a few baffle tanks this way however yours has a fracture which looks like it could run and hence drilling it out and replacing it with a bulkhead would be the best solution. The pipe looks about 32mm OD ? and that fracture spreads a further 10mm ? in which case a 50mm bulkhead should cover it (needs a 61-69mm hole) then just cap it off if it's not used.

 

[Ridgeway]

If you want a cheap and cheerful bodge solution then a load of CT1 would work, it's flexible, food safe and WILL seal that crack. Not pretty though...

 

[Treeeev]

Mikey

In the first instance I would try and repair the split by plastic welding using a soldering iron. If this didn't work, you could get a "nut in tank fitting" from CAK Tanks (see here). This does however assume you have an access cap , if not CAK sell them as well

Cheers

Trevor

 

[Ridgeway]

Unless you're actually carrying out a decent weld by adding new material then I'd be wary of a "soldering gun" weld process. It will probably work but the joint could likely be weak and in that area that for some reason has been stressed before (I assume the poorly designed rigid outlet was the cause). It's either a flexible solution or cut out the damaged area and replace.

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[Lenny HB]

You can weld polypropylene don't use a soldering iron you will just make a bigger hole. You need a proper welding gun that feeds polypropylene into the weld.
Probably best to get it done professionally shouldn't cost much.

 

[berni109]

Having the same van I know the drain stopper fits inside that pipe in the tank so replacing it with a brass tank compression fitting is going to mean fitting a valve/tap outside but thats what I would do. Go for the best size that will still fit without having to enlarge the hole in the floor/van and fit decent sized plastic washers with plenty of plumbers mate sandwiched between the tank and washer.
Probably only once per year you need to reach the tap to drain down and you could bring that out to the side with copper or plastic.

 

[Mike Ferguson]

Guys, I’ve just come home and read all of your replies.

Thank you for all of your suggestions.

Having looked up what CT1 is, I like the bodge solution of using copious amounts around the joint but I know it will always worry me that it might just fail at the worst possible moment, dumping gallons of water inside the van.

So, tomorrow I’m going to take Berni109’s advice and cut the pipe off, make good the hole, then obtain and fit a brass tank compression fitting together with a short piece of pipe and a drain tap underneath the van. Popping underneath the van a couple of times a year to turn the drain valve will be easier than removing the current drain stopper located inside the tank. It will actually be an improvement over the original.

I’ll let you know how I get on.

Many thanks.

Mike

 

[Mike Ferguson]

So, I cut the old drain pipe off and fitted a brass 22mm tank connector. A short piece of copper pipe now goes through the hole in the floor and has a ball valve attached to drain the tank from under the van.
I did consider attaching an elbow where the pipe comes through the floor and running a short piece of pipe along so that the valve could be located closer to the sills. I didn't bother in the end as I can reach the valve ok and didn't want to drill more holes in the floor for brackets to support the pipe.
I have attached some pictures. I have now covered the ball valve with a plastic bag and a zip tie to protect it from mud etc.. I have also placed 2 pieces of timber to the front of the tank which will prevent it from moving forward should the straps that Adria provide come loose again.
I'm really pleased with the result. At the moment its leak free and seems a cost effective solution.
Many thanks for your help.

 

[berni109]

looks good and it will save you having to be up to your armpit in cold water if/when you need to drain down when the tanks full.
cant tell whether you have put some new mastic around the pipe where it exits the floor but that might be an idea just to be sure that no moisture can enter from underneath.

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[skylinersi]

only just caught this thread, but well done on the repair, looks to be a great job and future problem proof!

 

[Mike Ferguson]

berni109 - I haven't put any mastic around the pipe, so there is a small gap around the pipe. My logic being that if it ever leaks between the tank connector and the tank the water will seep down the pipe and fall onto the ground underneath the van rather than all over the floor on the inside. Perhaps I have no confidence in my repair! Perhaps I'll mastic around the pipe in a couple of months once convinced that my repair is sound.

 

[tonyidle]

berni109 - I haven't put any mastic around the pipe, so there is a small gap around the pipe. My logic being that if it ever leaks between the tank connector and the tank the water will seep down the pipe and fall onto the ground underneath the van rather than all over the floor on the inside. Perhaps I have no confidence in my repair! Perhaps I'll mastic around the pipe in a couple of months once convinced that my repair is sound.

The water tank in your loft uses the same system .......... .