Sealine F33 Water tank wont hold water when filled

[F33Man]

It seems our Sealine F33 won’t hold water when we fill the tank, we think the previous owner has left a drainage plug open in tank as it was sitting around for some time - although I don’t even know if the tank even has a drainage plug. Does anyone know how to resolve this?

 

[Divemaster1]

a) Pipe or connector leaking
b) Tank Leaking

Sorry, do not know of any watertank with drainage plug as lowest point is usually where pipe connector is. So for your sake, I hope it is a pipe leaking..

If the water pressure pump kick in even when not using water, you have a leaking pipe after the pump.
If not, you know it will be upstream of the pump... or worst case scenario, the tank...

 

[Ripster]

So you are filling the tank up and it appears to be holding water or it runs away quickly? If so the bilges must be full each time and the bilge pumps presunably go off to clear it? Or you have a seep/dribble and either water pump operates without the tap on to maintain the pressure or as divemaster said its before the pump and again going somewhere (into the bilges). Are you definitely filling the water tank (ours has an identical filler cap for waste extraction and if we filled this tank with water it would just come out of the overflow and not fill the bilges. Can you give any more details about the syptoms and the things you have looked?