I finally finished replacing all of the original hoses in my fresh water system. I used the opportunity to reroute the layout so that the area above the bilge access is free of obstructions and to add a drain option to aid in emptying the system for winterization.
I gleefully filled the tank with fresh water and was disappointed to see water flowing freely from the inspection port area of the tank as the tank reached maximum capacity. As near as I can tell, the leak isn’t around the removable cap and O ring, but appears to be coming from the female area of the fitting. This part of the port is bonded to the plastic of the tank by some kind of hard white sealant.
Does anyone know how I can remove the port fitting from the tank to reseal it without breaking what must be a 30 year old piece of plastic? Alternatively; what about the idea of just coating the area in some silicone and hoping for the best?
Thanks in advance for any advice on how to fix this annoying problem.
I have the same issue on C.A.T. when the tank is under pressure (overfilling) but it is negligible while heeling with full tanks so I just live with a small amount of fresh water in the bilge when filling the tanks. Given the similar age of our Beckson ports I share your concern that the aging plastic will break if you attempt to remove them. I already lost quite a few of the grip tabs around mine just opening and closing it. Can’t think of any reason why silicone on the outside of the port wouldn’t work assuming you prep the tank in that area. The Ronco installation instructions recommend those not be sealed so I’m not sure if the sealant will take on that type of plastic.
RONCO MARINE TANKS should always be stored out of direct sunlight and protected from freezing. Prior to installation, tanks should be at room temperature for a minimum of six (6) hours. The tank must be installed on a flat or contour matched surface, be clean and totally supported in all planes with 1/2" - 3/4" marine plywood or equivalent.
Install tubing and fittings so that there are no points of stress on the tank. use elbows to prevent partial bending or collapsing of the tubing when a change in direction is required.
Plastic tank connections are designed to seal dry. Compounds such as sealants, pipe dopes, greases, petroleum jellies, glues or adhesives are not to be used. Normally, hand tightening will provide adequate seal. On occasion, a slight tightening with a wrench may be required. To avoid damage to seal fittings, do not apply excessive force. Do not exceed 1/4 turn after hand tightening.
Do not install metal fittings in the plastic tank as the materials are not compatible.
Should you desire to test the potable water tank or water system for leaks, fill with water and check visually.
I have the same problem. I tried replacing the o rings with nice new fat ones and it didn’t help. They just leak when filled to the top so there is always a bit of water in the bilge after filling. Like James said, that’s just how it is.
The unfortunate part is the holding tank has the same issue. It’s the same type of tank and the same hatch. So try not to ever fill it to the max and if you find out how to seal a tank, do this one too. West Marine in Florida had a special product designed just for repairing these types of tanks. I believe it melted the plastic a bit. I cant remember what it was called.
My port side original tank cracked. I tried to repair it with silicone but this did not stick to the plastic. I tried to melt the plastic with an iron to seal the crack and this worked but the area was weak and just split again. I replaced the tank with a bladder and am very happy with it.
Tom I had a small crack at the vent connection to the top and side of my holding tank .
I tried using the point of a soldering iron to melt and join and it has held up for about 10 years .
Bob Jenkins
Good News 30U. #323
Penetang
I lube the o rings on the inspection caps each year with teflon grease. and do not over tighten.
I did make permanent seal on a tank crack with a 2 part 3m product# 3M™ Scotch-Weld™ Structural Plastic Adhesive DP8005 , was $50 for 45ml.
The water tank inspection ports are fussy and you have to be careful that they are engaged before you gently tighten them.My rings have a silicone seal and acts more like an o ring rather than sealant. So far no leaks…
A trick I learned many years ago with plastic tanks was to drill a small hole at the end of the crack. This prevents it from spreading further. I did this on my holding tank 10 years ago and then applied 5200. It’s still “holding”.
Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA