Drinking water pump dead?

[BravoVita]

Trying to figure out how my drinking water system is configured. There is a 12 volt Johnson pump on the fill line that produces a suction from the water tank and the only other connection on the tank is an overflow at the top. I imagine when the main inlet produces water pressure, the pump should have some type of relief to allow the tank to fill however the tank is not filling. Bypassing the pump allows the tank to fill so I believe the pump is either toast or I just have no idea what I am doing...

[Snore]

With questions like this it really helps to know the make and model of the boat.

My boat has three hoses off the potable tank. 1.5" fill hose direct to the deck fitting. 3/4" vent hose and a supply hose (1"?). The pump is located on the supply hose.

Hope this helps.

[BravoVita]

Originally Posted by Snore

With questions like this it really helps to know the make and model of the boat.

My boat has three hoses off the potable tank. 1.5" fill hose direct to the deck fitting. 3/4" vent hose and a supply hose (1"?). The pump is located on the supply hose.

Hope this helps.

85 sovereign 28 foot but I suspect the pump is not original. For sure there are only 2 lines on it. Photo of the pump to follow. Really just wondering if the outlet is also an inlet because of the pumps operation/configuration.

[valhalla360]

Typically, the pump draws near the bottom of the tank. It can create suction so the pump itself can be above the bottom of the tank.

There is also typically a vent at the top, which relieves pressure when filling an suction when being pumped out.

There is also typically a filling inlet that is large enough that air can escape around the incoming water.

[HappyMdRSailor]

You need a vent line my friend !

[a64pilot]

From what you have stated, you have no vent line. When you remove water, of course you have to let air in to replace it or you pull a vacuum on the tank, eventually you will either collapse the tank or reach the highest vacuum the pump can pull and no water will flow. Long before this of course water flow will slow down.
Checking if you have a vacuum and if this is the problem is very easy, just remove the fill cap, if everything returns to normal, then either I suspect your vent is clogged, or you need one.
I'd suspect you have a clogged vent as that is common and I'd be real surprised if your boat was manufactured without one. I have seen vent lines that connect to the fill line so they are not immediately obvious, I assume this is done so they didn't need to add another opening to the water tank.

[a64pilot]

Your post is a little tough to figure out, but you have a pump that fills your tank? I assume another that supplies pressurized water to the boat?

[Sailmonkey]

What It sounds like your describing is a shore water connection. Does your "fill line" attach to the hose? If so it's not a fill, rather a connection for dock water.
There will either be another fitting on the deck for water, or maybe like our boat, you open an inspection port on the tank top to fill it.


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[sailjumanji]

Boy, your original post is confusing. Water tank has a fill line, and a vent line, and supply line going to the suction side of the pump. The pump pressurizes the house (boat) water piping, that is hooked up to faucets, spigots, etc. You might have a pulsation dampener tank on the pressure/outlet side of the water pump, but that is a relatively small vessel. My system does not have one. If you water pump is not pressuring the system, the seals have probably gone out (unless the motor is not turning, in which case you have burned up the motor). You can typically buy seal sets to replace, or the price of a water pump is not so high as to be an issue. Just replace it. I carry a spare fresh water pump onboard, and have occasion to need it in the middle of a cruise. Water tank is low in the boat, and very difficult to access without a pump. Or certainly it is difficult to take a shower without a pump!