Q&A on Causes of Loss of Water Pump Prime

Missing gasket can cause lost pump prime

i just had my flortec body part number N76-46P replaced. the pressure trank has n pressure inside the tank. When i was pouring water inside the hole to prime the the tank an pump i noticed water running outside where the flortec body connects to the pump.

is there suppose to be a gasket in between those pieces or inside the body for it to seal off ?

an i dont know what was suppose to be inside the flortec body part i was trying to make sure i had all the pieces inside it. i did not get anything with the body but the shell . an do i need to hook up electric to the pump when im trying to prime it? And will I need to add any ar the pressure tank or will it build up its own? On 2018-05-01 by jessie

Explanation by (mod) -

It sounds as if a gasket was omitted or the pump not successfully re-assembled. Until that is repaired an air leak at the pump can cause repeated loss of pump prime.

The question of adding air to the water pressure tank is a separate issue, not affected by loss of pump prime.

See details at WATER TANK AIR HOW MUCH TO ADD

Well pump loses prime every 2 days due to air leak at pump / well attachment

My well is losing prime and about every two days it is noticable by the loss of pressure coming out the faucets.

I re prime the well and it's fine and over a couple of days loses pressure again. I have an above ground pump.

When I shut off the power (to be able to hear) then pour water over the pump, I can hear the air leaking out (it making a squeaking like sound).

When I put my ear near the pump and it sounds like it is coming from where the pump attaches to the well, shaft, pipe that goes into the ground. I'm hoping that maybe there is a seal between the two metal plates where the pump attaches on top the well. On 2016-09-22 by Jason

by (mod) - re-make plumbing connections at the well head

Indeed if you can remove, clean and replace the well cap and seal and re-make the piping connections there, you'll stop the air leak in and that ought to stop the loss of prime - and perhaps save you the costs of pulling the whole well pipe to replace a foot valve.

Take care not to drop pipe or materials down into the well.

We lose water pump prime when we run outside spigots

I need help. If we use any of our outside faucets, there are three of them. We very quickly lose prime. Any suggestions? If we replace them will that help? Or do we just never use the outside faucets? On 2018-06-12 1 by Paula

by (mod) -

Thanks for the interesting and unusual question. I'm not familiar with a reason that using an outside faucet would cause loss of well Prime.

Generally if you're losing Prime it's because there is a leaky foot valve or a leaking well piping such that the pipe between the bottom of the well and your above ground pump leaks back into the well or into the ground feeling that pipe ultimately with air. A pump that's just seeing here cannot her a water.

IF you have a simple outdoor faucet or hose bibb that does NOT include an anti-siphon check valve AND IF if the spigot is left open then it's possible that when your well pump stops running and

I suppose it's possible that the anti siphon feature of an outdoor faucet could be leaking air into the system in combination with a leaky foot valve. Those are things your plumbing will check.

Is my well pump shot if it leaks water?

Is my pump good if it does not hold water and it leaks out the back? On 2018-01-11 by Monica Welch

by (mod) - pump may be repairable depending on what is actually leaking; water leaks out also may mean air leaks in & lost pump prime

Monica

If the pump is leaking it needs repair or replacement - you risk water damage and of course loss of water.

Just whether or not the pump is repairable depends on the pump type, age, model and condition. If the leak is at a gasket or a loose fitting the repair should be easy and not costly.

If the leak is due to a worn-out pump motor bearing repair may be possible but you'd want to compare the repair cost with the pump replacement cost.

Watch out: when water leaks out of an above-ground water pump it's also possible that at other points in the opeating cycle air leaks into the pump - resulting in loss of pump prime. - DF

How to fix a 2-Line Jet Pump that Loses Prime after 2 Hours

I have 2 line jet pump which loses prime after 2 hours. Can i fix a valve on the drive line (1" pressure pipe) so that i can directly pour water into the drive line. Is there any risk involved in this procedure? On 2017-05-20 by Ibrahim

Explanation by (mod) - add a priming tee or tap and fix the leaky foot valve

You can try adding a valve at the pump to make priming easier, but it'd be more effective longer term to find and fix the leak: probably a bad check valve or bad foot valve.

Watch out: If you just pour water into the suction line and the drive line you still risk leaving the pump impeller assembly dry - running dry can damage the pump

My opinion is that a pump losing prime in two hours is serious enough that the faulty check or foot valve needs to be replaced. Re-priming the system is a short term "band-aid" that can keep you with water supplied while you wait for your plumber or well repair tech to fix the trouble.

Shallow well loses prime unless we keep the pump operating frequently by leaving a trickle of water running

I have a shallow well nobody will work on and will pump fine for days if I let a trickle of water flow in the tub so the pump has to come on every half hour or so.

If I don't have water flowing for a couple of hours the pressure stays constant (even for days) but just cycling the pump doesn't get it to work. I have to open up the pump prime fill nut a slight bit to let the air excape then tighten it and turn on the pump, then repeat this 5-8 times until enough air has been purged out to get water to flow.

There is a check valve in the pipe on the suction side of the pump and I've tried to test for air getting in at one of the hose clamps.

I don't understand how air can be getting into the system at the foot valve...isn't it like a straw where you hold your finger over the top and the water can't flow out of the bottom, so air must be getting in somewhere where the line is above the water level?

Any help with how to test for air being pulled into the line would be greatly appreciated. Also, the 1" black poly line goes down through a concrete floor so pulling out the line to replace the foot valve is going to be a problem (it's an old lake cottage with a utility/pump room) - David - 12/4/2012

Reply: tricks for finding and fixing a "hidden" leak in plastic well piping: check the connections

David,

I agree that having to keep water running and thus the pump running is most likely avoiding loss of prime.

What's odd is that the pressure stays constant, but you're having to purge air to get water flowing again.

I don't think air is likely to be entering at a foot valve as it's under-water (unless water level in your well drops completely below the valve);

Air can leak into (or water out of) plastic well piping at connectors secured with hose clamps, even though such leaks may not be immediately obvious. At a shallow well served by a one-line jet pump I installed a water filter that used a clear plastic canister. When the pump would run I could see air bubbles appearing inside the filter canister.

Experimentally I added a second hose clamp at each of the above-ground well piping connectors that I could easily access. One of them turned out to be the culprit. As soon as I made a better connection there the air bubbles stopped.

This problem is a reason that well pipe fitters don't like to re-use plastic pipe connectors (elbows, unions etc) that have been disassembled. Every time we heat-up the plastic pipe to re-insert the connecting fitting we are stretching the plastic slightly. The connection may be leaky but look fine.

So if there is enough slack to do so (often not) we will cut off the previously-used end of well piping, re-heat the pipe, then insert a new connector, when restoring or repairing plastic well pipes.

From your description it sounds as if you have a one line jet pump. On a one line jet pump the air-leak in to the system can be at any connector above water, as when the pump is running it is "sucking" on the well pipe between the pump and well bottom.

On a two-line jet pump the air leak is more likely to be discovered on the suction line, as the pressure line, sending water down into the well and then back up through the venturi-operated water pick-up is under pressure - a leak in the "down" line will squirt water out, not draw air in, when the pump is running.

See PIPE / HOSE CLAMP LEAK REPAIR

Reader follow-up:

David

You've given me what I hope is a good idea...if I heat the poly as I tighten the hose clamp it may conform better and seal off any air from getting sucked into the line which allows the water the line to fall back into the well.

I think the reason the system pressure doesn't drop is that the check valve near the pump inlet is keeping water under pressure from getting back through the pump and back to the well, so the air leak is probably on the well side of the check valve (I wondered if the check valve brass casting might be porous and allowing air in).

I will try to improve the hose clamp seal (there are two clamps at each hose connection) and report back the results.

Reply:

David

I have once or twice found a cast-brass valve or check valve with a defect or leak, others of course can be cracked by mis-handling or freezing. And we found one with a "hidden" pinhole leak in the casting of a new check valve.

If you don't have extra length to cut and re-make the plastic well line fittings, try adding a 2nd hose clamp at those fittings.

Lost pump prime traced to debris in the pump impeller

I lost the prime on my pump and tried everything to correct the problem when a neighbor suggested I may have debris in the IMPELLER CHAMBER.

I scoffed but went ahead and took the CHAMBER apart.. Sure enough I found about 7 small pebbles at the bottom that stopped the impeller to spin freely and create the pressure needed.

Reassembled the chamber and like magic the water pressure zoomed to the normal range. Apparently I had cleaned the well and diturbed the small pea gravel on the bottom and it sucked the unwanted debris into the system. Just my 2 cents. (June 14, 2014) Ken from Lakefield Ont.

Reply:

Thanks for posting such a helpful tip.

Next time you have reason to pull the well piping, check the screen on the foot valve to stop admitting debris into the pump impeller.

Driven point well, no foot valve: repeated loss of prime burned up the pump

My well is a shallow design with only a well point (no foot or check valve) kept losing prime fried the pump have a check valve on the suction side of the feed. Only.

Was told by my well man that was sufficient but the pump vacuum gauge showed wide swings in the gauge it took a few minutes to finally build up enough pressure to start the first zone sprinklers.

Also frequent starting of the pump which clicked off by the pressure switch , finally did not shut off and boiled the h2o in the casing.what should I do to correct this mess. Thank you On 2018-09-04 by Carl Bellero

by (mod) -

Usually there are two issues here

First you're missing a check valve, perhaps right at the pump, and thus losing Prime OR the check valve at the pump is leaking.

Second of course the well capacity and pump capacity have to be matched to the water usage rate of your sprinkler system.

If the sprinkler system is demanding more than you're welcome delivery you can sometimes solve that problem by dividing the sprinkler system into sections and running only one at a time.

Frankly, I'm doubtful that most driven point wells could produce so much water that you can run an irrigation or sprinkler system.