08-29-2026, 11:52 AM
I have the same problem with my centerline tank in my 4000 Express. It was leaking about one cup of water per day. I’m still researching my options, but currently believe tearing up the floor is most likely going to be necessary. The one tank repair company I spoke with specializes in fuel tanks where pitting from contaminants is typically only along the bottom. With water tanks, the pitting can be throughout. I’m guessing the tank also has baffles across it so installing a bladder would require tearing up the floor anyway to get access for their removal.
In the interim, I decided to just isolate the leaking tank from the tank on the outside of the starboard stringer. It wasn’t easy, but I managed to install a shut off valve in the hose connecting the two tanks. This still leaves me 72 gallons of water and I can always open the valve for longer trips if I don’t mind dealing with the one cup of water loss per day.
In the interim, I decided to just isolate the leaking tank from the tank on the outside of the starboard stringer. It wasn’t easy, but I managed to install a shut off valve in the hose connecting the two tanks. This still leaves me 72 gallons of water and I can always open the valve for longer trips if I don’t mind dealing with the one cup of water loss per day.
