water tank plugged

[Don S/V ILLusion]

Before taking compressor to the tank discharge (to back flush), I'd be interested in any other, maybe safer suggestions how to unplug one of my water tanks from which I can't get water to flow to the pump.I already tried to suck a vacuum to no success and the tank vent and water filter isn't the problem so I'm looking for other ideas how to remove whatever is plugging the discharge line without having to cut open the tank.

 

[KorculaChris]

Don,

what have you tried so far as far as locating the blockage? Have you disconnected the discharge line at the tank to see if water is available there? It is rare for a tank outlet to get blocked unless either the tank has partially collapsed or some foreign object is in there. I take it there is no access plate? It is a good idea to install one (there was a recent thread on it) http://www.seabuilt.com/Good luck, keep us posted.

 

[Alex]

Remove the valve?

May be something dropped into the tank and now blocks the outlet. Did you try to remove the valve and stick a cloth hanger in there? May be doring manufacturing some junk got left in there.Usually water tank has a clean out port. You can use a wet and dry vac to clean out the inside.

 

[GuyT]

Maybe it's not a clogged line??

You have multiple tanks - Maybe your problem is with the diverter valve?You could disconnect the discharge line and run wire back through it.Welding wire would work great if you can get it. Bare copper - 12 gauge would also probably work.

 

[RichH]

How is the tank vent ?????

If the vent is plugged .... usually with a mass of bio-growth .... the tank will appear to be blocked. If you have a metal or thin walled plastic tank and if the vent is totally blocked you wont be able to draw down any water ..... and you risk imploding / breaking the tank when the pump begins to pull vacuum. The tank vent line can easily plug and become fouled due to the high humidity in the vent. All sorts of noxious 'crap' will be found to be growing / thriving in water tank vent lines if not protected with a bio blocking filter. Such biofouling of a vent line will also be the source of constant tankage bio-contamination. Totally disconnect the tanks vent line at the tank and see if your blockage is 'removed'. IF the vent line is blocked, entirely replace the line with new tubing ... and then consider to put on a bio-blocking vent filter. You can make a bio-blocking filter by simply applying a big 'wad' of bandage gauze over the end of the tube; just keep the 'wad' dry and change at least yearly .... or buy an industrial hydrophobic 'capsule' filter ... about $60.00. The most probable main source of tank bio-contamination is through the vent; it 'aspirates' spores and other bioforms EVERY time you draw water from the tank. Also check the (bad practice) outlet of the vent somewhere on the 'side' of the boat as 'mud dauber' wasps love to build their incubation nest in these.

 

[Don S/V ILLusion]

any other ideas?

Thanks for the replies so far but there is no water in the line, the valve is clear and, as I said, the vent isn't the problem. Chris - will try your suggestion if I can get access to the tank line at the tank itself. It figures this is the only (one of four) tanks for which there is no cleanout.

 

[Rich Stidger]

Don, if you open the fill port does the water flow

If the water flows with the fill port open, then that would suggest that the vent line is clogged. If still no flow, then the vent is probably OK (it could still be clogged but then you would have two faults not one).If you still have no flow with the fill port open, AND you are sure that there is water in the tank (yeah, I know, but I have overlooked the obvious too many times), then I would loosen or disconnect the line from the tank to the manifold valve assembly. If the water flows, you are now down to the valve on the manifold itself.I presume that the tank in question is the aft 40 gallon tank. You should be able to gain access to the side and the exit of the tank from the removable panel in the aft cabin. Since it is a poly tank you can observe that there is water inside.