Water pump issues.

[Ford Prefect]

My water pump had failed so I replaced it with an exact model of what worked before, a Johnson 3.5 gpm. While I was replacing the pump, I decided that it was time to replace the hoses and tank. The fiberglass tank, being 30+ years old was full of leaks and when I opened it up, was covered in mold and all sorts of things I'd rather not think about.

In any case, in place of the tank, I put in a bladder system (actually put it in the tank) as well as replaced the entry and exit hoses. So now I have clean hoses and storage for my water.

My problem is water getting to the faucet. When the pump is engaged, the suction is pulling the water out of the bladder tank incrementally. When it reaches the faucet it's basically burping water between pauses of air.

There's no leaks in the bladder or the hoses pulling air in that I can see. The pump is creating suction, as I can see the water level rise up to the entry point of the pump, but not all the way, as I can see an air pocket right at the top. Any ideas as to what's preventing a constant flow? Is the pump simply not strong enough to pull the water through?


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[model 10]

What about a vent?

[Ford Prefect]

there is a vent line prior to where the water enters the bladder. I placed a Y-connector about 18 inches before the bladder, so any overfill would exit there and not burst the bladder. I can't see how that would affect the pump. the filling water line (as well as Y-connector for vent line) enters on top of the bladder. Water leaves the bladder to the pump through a line located at the bottom. Gravity says water would go before air. If there was any air sitting in the exit line from idle use, switching on the pump would eventually remove all air in the line, but i can run it for 10 minutes and still no improvement.

[Jsta_Rebel]

Originally Posted by Ford Prefect

there is a vent line prior to where the water enters the bladder. I placed a Y-connector about 18 inches before the bladder, so any overfill would exit there and not burst the bladder. I can't see how that would affect the pump. the filling water line (as well as Y-connector for vent line) enters on top of the bladder. Water leaves the bladder to the pump through a line located at the bottom. Gravity says water would go before air. If there was any air sitting in the exit line from idle use, switching on the pump would eventually remove all air in the line, but i can run it for 10 minutes and still no improvement.

No install photos of the y connector, but you need to have a way for air to enter the tank /bladder as water is being drawn from it. If not, you will create vacuum on the bladder and your pump will not pump anything until the tank burps causing intermittent flows. Just like a fuel tank on an outboard if the vent valve is closed, the motor will run out of fuel even with a full tank. BTW, do you have any filters after the pump that could be plugged up??

[motion30]

Remove the fill cap and see if that helps

[svHyLyte]

We have two 50 gallon bladder tanks aboard our boat, each fitted with an umbilical hose with a cap that can be unscrewed to "burp" the tank to remove any air that becomes entrapped within while filling (which can happen as the water flow can/will become "aerated" as it passes through the hose nozzle). Once that's done and we gt only water, the caps resealed. One doesn't need a vent on a bladder tank. As water is drawn out, it collapses due to ambient air pressure (just as does a water balloon as the water is released) allowing an undisturbed flow of water to your pump. Adding a "vent" disrupts this action. You do not need an "overflow" line to prevent the tanks bursting. Once they have reached capacity, water simply backs up through the fill line and overflows on deck around the fill fitting (unless of course you have thoroughly jammed your fill hose into the deck fitting which you should not).

FWIW...

[Ford Prefect]

Interesting. I'll experiment with sealing the vent and let you know if that does the trick.

Thanks


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[JstaRebel]

Originally Posted by svHyLyte

We have two 50 gallon bladder tanks aboard our boat, each fitted with an umbilical hose with a cap that can be unscrewed to "burp" the tank to remove any air that becomes entrapped within while filling (which can happen as the water flow can/will become "aerated" as it passes through the hose nozzle). Once that's done and we gt only water, the caps resealed. One doesn't need a vent on a bladder tank. As water is drawn out, it collapses due to ambient air pressure (just as does a water balloon as the water is released) allowing an undisturbed flow of water to your pump. Adding a "vent" disrupts this action. You do not need an "overflow" line to prevent the tanks bursting. Once they have reached capacity, water simply backs up through the fill line and overflows on deck around the fill fitting (unless of course you have thoroughly jammed your fill hose into the deck fitting which you should not).

FWIW...

Makes good sense. Thanks for the first hand knowledge.

[Ford Prefect]

Well, of course it wouldn't be that simple. I closed off the vent and nothing happened.I opened the vent and nothing. Either way, when the faucet is off, I get no suction up into the pump. In both instances, when the faucet is on, water will travel up towards the pump, but stall out at the lip. Whether the vent is sealed or open, the result is the same. I'd send a vid, but it doesn't look like I can upload one via mobile. 1st pic shows line bone dry when faucet is closed. 2nd pic faucet is open, but water level is not getting all the way into the pump. Vent opened or closed, same result.




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[Stu Jackson]

Have you considered that the major kink in that hose is causing your issue? Severe restrictions in hoses, such as shown, will and can reduce flow to only a trickle, if you're lucky. Is there room to straighten that hose out?

[Ford Prefect]

Not a lot, and the old line was placed in the same location, though it was a thicker braided version with less bend in it. I can certainly go pick up 2 feet of the old stuff and try it out.


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[bglad]

Sounds like a vacuum leak. If that is one of the type pumps that has clipped in fittings sealed with o-rings the way you have it mounted may be pressing against them compromising their ability to seal the fitting. Pump evacuates air from the line but cannot lift the water. Take the strain off its fittings and see if that helps.

[jamhass]

Had a similar issue on installing a new pump. Turns out one of the plastic inlet fittings cross threaded creating an air leak which kept the pump from priming. Fixed that and all is now well.

[Ford Prefect]

Sorry for the delay in responding; had been studying for the 100 T and that took all my spare time. Finally had a chance to try your suggestions. Placed the pump an inch higher to straighten out the kink and replaced the plastic fittings that lead into the pump. Works exactly how it should! Thanks guys, the advice was spot on 👍🏻🍻


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[Bits n Bytes]

Jamhass - thank you for your post - we had the same issue and your post helped us correct it!


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