Leaking Water Tank

Feb 27, 2004
172
Hunter 335 North East, MD
So this past fall I installed a Beckson 6" inspection port with a gasket in my plastic water tank. When I filled my water tank for the first time this Spring I ended up with a lot of water in my bilge. (Good test for the bilge pump !) Upon trying to locate the cause- the top of the tank was wet both at the junction of the fill pipe coming into the tank and around the new inspection port . I tightened the screws of the inspection port. I haven't refilled the tank yet to see if I fixed or indeed if this was the cause- but I was wondering whether there is any caulk or sealant that I should be using as well.

Thanks
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
If you do a search for food grade sealant, adhesive or caulk you will get a lot of choices.
 
Jan 7, 2011
4,727
Oday 322 East Chicago, IN
I assume you mounted the inspection port ring to the tank with some adhesive or a gasket ? If not that is surely your source (or A source) of a leak. You don’t want to seal the threads on the part that screws out of the ring, or you won’t be able to get it out again. I do use a little superlube on the o-ring to keep it pliable and to provide a better seal.

Is it something like this?
1619474734778.jpeg


Greg
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
As @Tally Ho has mentioned, you will need a sealant under the outer ring. These inspection ports are not usually sold with a gasket or sealant.

The tip of the day is that very few sealants will stick to polyethylene. The only reliable one I've found is Permatex 2 and you DO NOT want that in contact with your potable water. Never had need for a food grade sealant on my potable water tank so no experience there. Before installing the sealant, smear a small sample on the top of the tank and come back 24 hrs. later and see if it's stuck to the top of the tank.

Try a food grade approved teflon sealant and it MAY stick. Then again, it may not. Just keep on trying.
 
Jan 7, 2011
4,727
Oday 322 East Chicago, IN
The other trick is to use bolts and washers, not the small screws provided with the inspection port...especially if installing in a poly tank. Hard to get much clamping force when using the small screws in plastic.

Greg
 
Feb 27, 2004
172
Hunter 335 North East, MD
Thanks yes I did use a gasket which I got from Beckson the port maker and bolts and washers as well I made need to tighten more. Greg my port is like your picture but with a clear in part, let me lube the gasket and tighten the bolts and report back. Thanks for the feedback
 
Oct 22, 2014
20,995
CAL 35 Cruiser #21 moored EVERETT WA
While you are at his fix, be sure to check that your vent line is functioning. You could be filling the tank and what you are seeing is moist air venting out the inspection port and fill pipe.

Those inspection ports are not intended to hold water under pressure. Filing your tank can pressurize the tank.