Pump Priming the Easy Way

This system will help you get a water pump working in no time.

pump-priming port

Adding this simple shutoff valve to the supply is the key to easily priming a water pump.


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If you pump water seasonally from a river or lake for irrigation or household use, you're faced with what could be a serious and ongoing hassle. Depending on the kind of pump you're using and the length of intake line, priming your system in the usual way — by pouring buckets of water down into the pump and pipe — can be slow, messy and infuriating. But there is a fast and easy alternative, which I’ll explain below.

Water Pump Basics

Water is the only liquid that expands as it freezes, and this is why most seasonal water systems need to be drained before winter. Otherwise pump and pipes will crack under the strain of expanding ice. But when it’s time to get your pump working again as warm weather arrives, you have to refill the whole system with water. This operation is called priming, and it's necessary because water pumps can't move air. All this sounds easy enough in theory, but there are two reasons it's not easy in real life.

First, seasonal water systems are not usually designed for hassle-free priming. You'll typically find a single, half-inch-diameter plug in the top of the water pump — way too small to conveniently pour the 5, 10 or 15 gallons of water required — and you usually need to haul all this by hand in buckets from the water source.

If that wasn't enough, all the air has to get out of the system to make room for the water you're putting in.

The Easy Priming Method

The following method has worked flawlessly for more than a decade for me. For less than $30, you can install simple plumbing fittings on the end of your water system intake line, which will make priming a 10-minute project.

The secret behind the system is that it's a lot easier to push water up into the end of an intake line from a lake or river than it is to dribble it down from the top. But to make this bottoms-up arrangement happen, you need to install what I call a priming port.

You won't find anything by this name in hardware stores, but you can assemble one easily using standard plumbing parts. All you need are a tee fitting, some clamps, a 90-degree elbow and a shutoff valve arranged in the way you see in the photo. The priming port is installed near the end of the intake line within a few feet of the foot valve that goes into the lake or river, and prevents water from draining out of the pipe.

To use the system, simply open up the valve that's part of the priming port and undo the vent plug on the top of your water pump (to let air escape as water fills your intake line). Then hook up a hand pump to the priming port and push water all the way up the intake line until it starts coming out of the hole in your water pump. We use a Guzzler hand-operated bilge pump to do this. It's designed for use in small boats but works great in this application. If you have running water available from a garden hose, simply configure your priming port to accept the end of the hose, turn on the water and your system will be primed automatically. When priming is complete, close the valve, remove your pump or hose, put the intake line into the lake or river and switch on the pump. You should be set for the season!

scott _2
7/26/2009 9:25:31 PM

Excellent post. I've been looking for a solution for the same problem for the house and garden water system. As for the priming port, I find this works just as well just after the pump and before the start of the intake line. The procedure I came up with is to have the following connected in series; pump check-valve tee connection with water faucet(near pump) intake line float valve on the end of the intake. Procedure for priming is: Attach a hose the the faucet in the tee. Connect a submersible (preferred) or hand pump to the hose on the tee faucet. Partially open the small air/water intake at the top of the pump. This is location where you'd be normally pouring water to prime the pump. Submerge the priming pump in a large volume of water (a pool works well). Open the faucet and allow water to prime the intake line. Wait until no air escapes from the intake at the top of the pump and hand tighten the bolt. This bolt should have Teflon tape. With the float valve submerged in the well or lake (source), start the main pump. Continue to run the hose to the tee until the pump reaches 40-60 psi. Turn off the faucet and wait to see if the pressure is maintained. If the pressure drops back to 0, repeat by opening the faucet again and check for air coming from top water intake. Loosen if needed to let out the air but DON'T LEAVE IT COMPLETELY OPEN, water will shoot out of the opening when the pump prime is established. Once the pressure returns, the faucet is closed and the prime established, securely tighten the air vent on the pump. Stop the submersible pump. Always check all connections and use Teflon tape for all screw joints. The principle is that water will flow into the tee and down to the end of the intake line float valve which will trap water at that end. As the water rises in the intake line (establishing the prime), it pushes the air up the line through the check valve and into the pump where it wi

earl thompson_2
11/14/2008 11:12:15 AM

Why not more explanatory pictures and diagrams in your articles. It would make understanding the articles much easier. Thanks

7/28/2008 6:26:26 PM

You'll want to figure out how high the top point is that you need to move the water then find a pump body that has that "head" pressure rating. From there, it depends on what power is available to run it. Electric motor, windmill, human power, etc. As for your failed hose attempts, try installing spigots low on the side of your barrels to eliminate having to prime your pump. You likely have an air bubble in the hose you aren't overcoming to get water flowing.

ede ...
7/16/2008 10:54:57 AM

Good Article! I'm needing advise on what to use to get my collected rain water up to my garden, rather than lug bucket after bucket. Our backyard slopes down to our house. We collect rain water in many 60 gal barrels from the roof. I'd like to find a way to 'push' the water out of the barrels and up the slope to water my garden.... without buckets! I've tried several ideas to syphon it through a garden hose, to no avail! Help??