Hi all, noticed a drip from the drainage tap when draining , got a new o ring ? and seemed to have done the trick . Now there seems to be a drip from underneath the square housing but no leak inside the van ... any ideas anyone??
I have provided a link with an exploded view of the Cascade MkII hot water tank and all the components inside in order to identify the various parts to check. The only part the diagram doesn't show are the 4 long tie rods (very long thin bolts with nuts) that clamp the whole length of the water tank to the cowl.
If you are going to conduct an inspection you will firstly need a tube of appropriate sealant such as 'Seamseal CV' or 'Silkaflex' and an application gun as there are 4 fixing screws (item 9) in the square housing (item 13) which behind should be a water tight seal around the perimeter to stop any rain water gaining access which you will have to re-seal on completion. When removed, check for any cracks in the cowl and also inspect the pressure relief valve for leaks in the top left hand corner (item No. 12). If all is satisfactory and cannot find the reason for the leak then you will have to dismantle further by removing the whole tank as item No. 20 is a giant rubber 'O' ring that seals the cylinder to the cowl which is clamped together by the 4 long tie rods (not shown). The end of the tank (directly behind the cowl) is fluted (like a small trumpet shape) that the 'O' ring sits neatly in to so you could inspect this for any splits or damage but I doubt very much that this will be the underlying cause anyway because the 'O' ring is not subject to movement like the one behind the drain plug is.
However, before you attempt any inspection you could try wrapping some PTFE tape around the thread of the drain plug first just to see if that cures the problem because sometimes water can play funny tricks and may not be coming from behind the housing at all and still slightly leaking from behind the drain plug. It does happen over time due to wear and have to do mine each year when refilled the water tank after the winter season.
I had a complete nightmare draining down the water system for the 1st time as the previous owner/s obviously had no idea about maintenance, being my 1st caravan I had to learn a lot quite quickly, when I tried to remove the drain plug it didn't go well and I ended having to heat up a large screwdriver and push it into the plug to get a good grip then the plug just fell to a million bits when I turned it, then spent a lot of time cleaning out the thread, after all that was done I thought great and put the new plug in only to find it was leaking a little from low down, so took the plug out and put some vaseline round the O'ring, job done and no more leaks, aftewards I felt like a bit of an idiot with my mechanical work I should have thought a bit and realised that all rubber O'rings need a bit of oil, grease or vaseline to prevent leaks, what you use depends on what the useage is for so in the case of water I would say vaseline is the best to use.
To prevent further problems I put vaseline all down the thread of the plug as well, this I put my mechanical brain into gear and used it knowing aluminium will oxidise and create a really good bond with other materials whether you like it or not.
No not Vaseline or petroleum jelly to give it the correct name, it soaks into plastic and rubber so swelling it and causes more problems.
In truth I don't recommend anything on drain bungs and Silicone grease elsewhere. I also use a slightly different actually smaller 'O'ring. Not then I might add, bigger as sold on ebay as an 'upgrade'!!
As for the remaining leak, the whole heater is angled slightly towards the wall to aid draining, this also has the effect of delivering a leak from anywhere to the wall end of the heater.
So it's a matter of finding where the source is without assuming it's from where it's dripping from
following on from the thread of my earlier email, at the weekend I took off the outside housing and a 'plug ' in the top left hand corner (not the drain plug) fell to bits, I have a feeling its to do with the the hot water,, and looking at the diagram kindly provided by tango55 above... it looks to be in the same position as part number 12.... does anyone have any idea what this part is and if its replaceable or is it likely that I'll need the whole gas burner?
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.
Topic: Leaking carver water tank
