The water tank has long been a mystery to me. It's supposed to have a 110 gallon capacity, but it has never seemed like the tanks hold that much. I decided to test that perception: I used a hose to fill a five gallon bucket with a stop watch and figured out the rate of fill, then I timed how long it takes to fill the tanks. By my calculation the tanks held about 40 gallons. Today I set out to figure out why.
My first guess was that the vent was clogged. A clogged vent, I reasoned, would trap air in the tank, leaving less room for water. I followed the vent hose down to the tank, disconnected it and blew through the vent to find that it was working properly.
Then I opened up the access port of the upper tank (65 gallons) and found it had a couple of inches of water in it when it should have been empty - a clue!
I'd never set eyes on the lower tank, because it requires removing the saloon table and floorboards, but that didn't turn out to be too tough. When I had the tank exposed, the placard offered another clue: the tank holds forty gallons. The hose that fills the lower tank comes in from the deck filler, and tees to the upper tank. I followed that hose up under he nav station drawers, already sensing what I would find: A closed valve.
In order to fill all 110 gallons and use 110 gallons, there is a valve that must be open. Nice to know.
