Water Tanks

[aruggiero]

I have posted this twice because when I tried to start a new thread earlier it kept saying I didn't have permission. We have a 1980 37” Endeavour that has a 100 gallon water tank, We have a problem with one of the outlets on the tank. We can’t get water from it. It seems that there should be a tube or something connected inside but we are not sure. The water is drawn from the top of the tank. I called Florida Marine Tanks and they said that they need the model information from the tank before they can help. I went to the boat to check it and I can’t read the model number. It says it was manufactured in 1980 – Lot #23. It is a 100 gallon tank and the hose connections are on the top. It was manufactured by Florida Marine Tanks. I’m pretty sure that all the 37’ Endeavours have these tanks. It is very old and the numbers that I have here are all that are I can read. There are two hoses connected now and one more port that has a plug in it. The port that works is connected to the pressure water system. If the tank is COMPLETELY full the manual tap will draw water but once the water level drops below full it won’t work anymore. If the manual pump is connected to the port the pressure water is drawn from it works. I think it needs a pickup tube ore something like that in there – I’m not sure what it is called. It might be a very simple piece of plumbing but I don’t know what piece it would be. The inspection port screws are too stripped to remove it and see the difference in the port that is working and the one that isn’t. We are afraid we won’t be able to get it back on if we ever get it off. If you have any idea what the problem might be I would appreciate any information. I guess the real question is what plumbing needs to be on the inside of the tank to draw water from a top draw tank?

[k1vsk]

The tank has to be plumbed so as to draw water off the bottom, or close to the bottom. just like any other tank for water, holding tank or fuel tank.
These pumps can't suction water out of the tank, especially one which is vented as these must be. In other words, there has to be a pickup tube from the top mounted fitting or you are simply sucking air.