Water pump or pressure issue

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Wxx3

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Dauntless
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Kadey Krogen 42 - 148
Hi all,

I figured I should ask here before I pull what remaining hair I have out.

In the last few weeks, I have noticed my water pressure drops after a few minutes of use.

It then has a slight sputter, like it is picking up some air. Of course that explains the pressure drop, but I'm not sure of the mechanism that would enable it to act normally for a few minutes and then suck air??

It's a Shurflo pump. My air pressure tank shows a constant 40 psi

Thoughts?

Richard on Dauntless in Aruba
 
I think that you have a leaky fitting on the suction side of the pump, between it and the water tank. When you run the water for a minute or so it sucks a bit of air in which builds up near the suction of the pump until the pump can't pump any more. It then clears the air through the pump. That is the sputtering you hear. Then it is ok for another minute or so.

Find and fix the leak and your problems should go away.

David
 
Clogged aerators in faucets? Or crappy pressure at each fixture?

Sometimes crap builds up on check valves in pump head. Some can be field stripped, but I probably would not attempt unless you have a replacement pump available on the island.

Take suction hose off pump and blow into it, see if there is clog or leak between there and tank tap.
 
Is there a strainer before the pump? Same water tank? Did you check the valve positions on the other water tanks? Could be an empty tank and a slightly open valve.

Ted
 
Update

Fitting on suction side of pump had crack.
I replaced that, also put new hose between the strainer and Cu supply pipe.

No difference.

I think it could be partially blocked supply but it affects both tanks.
 
Same problem with dock water? Check for leaks when connected to city water and the pump is off.
 
I think that you have a leaky fitting on the suction side of the pump, between it and the water tank. When you run the water for a minute or so it sucks a bit of air in which builds up near the suction of the pump until the pump can't pump any more. It then clears the air through the pump. That is the sputtering you hear. Then it is ok for another minute or so.

Find and fix the leak and your problems should go away.

David

Yes. Agree. All faucets the same, but most telling, I can see air bubbles coming thru the new hose between the supply line and suction side of pump.

I did blow air into tanks, thinking clogged vents could contribute.

No change. Though ad wr pumped air into empty tank, when I opened both feed valves, air perculated into half full tank.
Maybe too much air for vents to handle.

At this point, this is rapidly becoming a spring project when dauntless will be resting in Costa Rica and Mexico in April and May.

Could also be a partially blocked supply line between where the lines merge into one and the pump.
 
Same problem with dock water? Check for leaks when connected to city water and the pump is off.

Oh, I forgot about that option. It's been 3 yesrs since I used it.

Thanks
 
Oh, I forgot about that option. It's been 3 yesrs since I used it.

Thanks

Ok
Hooked up directly to dock water.
No pressure drop, but no discernible leaks.
 
Have you looked inside the tanks for maybe some algae type growth? Might try back pressuring the line before the pump with city water pressure. If there is debris in the line, you may be able to clear it back into the tank. Might still have to clean the tank, if that proves to be the issue.

Ted
 
This probably has nothing to do with it but 40# sounds like a lot of pressure for your reservoir. I think they come pressured with about 20 pounds when they are new?

If there is too much air in there, the electric pump will not be able to fill the accumulator with very much pressure before it shuts off, you may get lots of pump cycling on and off?
 
Look for debris in pump intake. Remove the fittings from the front of the pump to make sure intake is clear.

Conall
 
This probably has nothing to do with it but 40# sounds like a lot of pressure for your reservoir. I think they come pressured with about 20 pounds when they are new...?

:thumb: The Jabsco small accumulator tanks come pre-charged at 10psi and the 2 gallon tanks are around 12 psi. There should be a Schrader valve where you can check the bladder pressure once you have bled off the water line pressure. Our water pump shuts off at about 45 psi. He maybe reading that pressure.
 
:thumb: The Jabsco small accumulator tanks come pre-charged at 10psi and the 2 gallon tanks are around 12 psi. There should be a Schrader valve where you can check the bladder pressure once you have bled off the water line pressure. Our water pump shuts off at about 45 psi. He maybe reading that pressure.

Exactly.

I put water back thru the lines, no sig chg.
I think it's an obstruction in the single line before pump
 
Try removing pump suction hose, close both tank supply valves and put water pressure into the pump suction hose to find the leak. Another method might be to fill both tanks, open the supply valves with the pump off and look for leaks. There may be a restriction as you mentioned, check the tanks supply check valves.
 
If you are still seeing air in the intake hose before the pump, then there is probably still a leak.

How is the water draw out of the tank? Is there a dip tube? And if you fill the water tank, does the problem persist, or go away?

I ask because I have heard of dip/pickup tubes that have developed leaks, either up where they pass through the top of the tank, or somewhere along their length. If the leak is exposed to air as opposed to being submerged, some amount of air gets draw in.

One test would be to rig a suction how from the pump intake, and run it right into the tank and down into the water bypassing the normal plumbing route. If that works, then your air leak is somewhere in the bypassed plumbing.
 
This probably has nothing to do with it but 40# sounds like a lot of pressure for your reservoir. I think they come pressured with about 20 pounds when they are new?

If there is too much air in there, the electric pump will not be able to fill the accumulator with very much pressure before it shuts off, you may get lots of pump cycling on and off?

Xsbank has a good point. I had exactly that problem with a new pressure tank. Was charged to around 40#. Paid WAY to much to have a plumber come out and let air out. Now at 22# it's perfect.
 
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