Insufficient tank pump out

[Bob Bell]

When we pump out our aft holding tank, it rarely gets down to within 2-3 inches above the pump out fitting before the Marina's Pump a Head stops pumping. We try refilling with fresh water and repumping, but with almost no improvement. Since the tank is about 12-14" high and we have 3-4 inches unpumped, we seem to be losing a lot of capacity. The forward tank is visually inaccessible as far as I know, but we expect that suffers from the same problem.ThanksBob Bell

 

[Peggie Hall/HeadMistress]

Pumpout fitting location determines how much

is left in the tank...'cuz when the level in the tank drops below the top of it, the pumpout (or macerator) starts to suck air and loses prime. It should be as close to the bottom as possible, which would only leave about an inch...if it's been installed too high, there's nothing you can do but install a new discharge fitting in the tank. I'm guessing that it's slight mfr'g defect in the tank--the person on the tank assembly line who was wielding the hole saw missed his target slightly. If whoever put the holes in the forward forward tank didn't also suffer from the same attention span disorder, you're prob'ly getting all but an inch or so out of it. Both tanks still should be rinsed out frequently, to prevent sludge from accumulating. And keep a very close eye on your tank vents--to make sure that they never become blocked. Never overflow the tank, backflush 'em every time you wash the boat. The link below will help you prevent a lot of "head aches."