Prout Water Tank Help...

[Trident]

I have a Snowgoose 35 which had had the in-keel tanks decommissioned and replaced with bag tanks. As these chaffed, leaked and generally were a PITA as well as holding only half what the keel tanks did I have re-comissioned the in keel tanks. I cleaned, repainted with potable epoxy, built new inlet and outlet and breathers, sealed the tops and was ready to fill when...

I found right at the very back of the tank, at the very top (part way back under the rear bunk for those familiar with the Snowgoose) a tiny copper "spout" glassed in to the tank top. It has a piece of microbore hose attached which has been cut off in the dim and distant past (the same hose as is used for a Webasto or Eber fuel supply so really small)

I have no idea what this would be for - because the hose is just cut after a few inches and left I don't know where it would have routed or what the purpose might be - the tank has a large bore breather already, AFAIK there were no gauges fitted to these boats (and I've never seen a manometer type gauge that would need a hose feed on a boat)

So can anybody shed light on what this might be and is there any reason I can't just seal it off?

Thanks

 

[vyv_cox]

It does sound very much like a level gauge, similar to the fuel gauge on early VWs. There was a rubber button next to the instrument head, which when pressed applied a small pressure to the tank. This was interpreted by the instrument as a level value.

 

[boatmike]

Whatever it is it is completely non standard and yes you can seal it off.

 

[coopec]

Trident

I am building a yacht and when I came to the water tanks I spoke to the resin supplier and told him I was going to build the water tanks integral into the hull so that the hull formed part of the tank. His response was a very emphatic NO!! He told me to go to one of the paint manufacturers who have developed special coatings. I have since found out that dangerous chemicals leach from the fiberglass lay-up and that is why they have to be coated.

When I spoke to the specialist at the paint laboratory he asked if I could leave the tank in direct sun for the epoxy coating to cure. I explained the tank is in the keel of the yacht. He said in that case curing is going to be a problem. He the talked about heaters etc but I left him a little undecided what to do.

Since then I have read we amateurs should not use two pot epoxy in a potable water tank as we cannot provide optimal conditions for a good cure. (the article pointed out even the Gougeon Brothers don't have approval to make potable water tanks) So I suppose the nastys then leach out of the epoxy if it is not cured properly.

I finished up making seven separate water tanks so I can take them out through the main companionway for maintenance, painting and of course it is a lot easier secure small tanks instead of a tank weighing 500KG. I am using a water based bitumen to line my tanks as it is far cheaper than epoxy and is approved by the WHO for potable water. I am sure the product would be available worldwide. (just do a search on "water based bitumen potable water")