Introduction: ~ World's Greenest WATER PUMP ~

Hydraulic Ram Pumps are very old technology that pump water using gravity and 2 valves to generate a repeating water hammer effect. The "hammer" pounds a little of the drive water into a pressure tank then up the delivery hose for your use. Why is it green? Because it's simple, reliable, pumps water without any engine, fuel or electricity or muscle power and can be made from mostly recycled materials.

The one I built has a few novelties that make it more reliable, cheaper and easier to operate than most of the plans you find on the Internet. It developed a steady 28psi pressure at the pump and delivered about 1,000 gallons per day where we wanted it.

last season, it hammered over 145,600 gallons of pond water up a steep hill to our garden over 700 feet away and over 100 feet higher than the pond! In the process, it saved us over 485 liters of diesel fuel we would have normally used to drive our diesel tractor to pump and tow the water around our farm.

The pump was built for about $50 worth of plumbing parts and a bunch of stuff that I had sitting in my scrap pile.

What's the secret? A strong gate valve - period.

Please have a look and enjoy the instructable and don't forget to rate it.

Please let me know if I can make it better or easier to follow somehow, and I will be happy to answer any questions that you have so post away!!

Step 1: Get Started!

Parts list.

You may want to print this picture to refer to later as an assembly guide.

Step 2: Build a Better Gate Valve!

All the available plans for ram pump valves are based on converting a conventional foot valve to operate in reverse. The trouble with this solution is you end up with a valve that is flimsy, wobbly and unreliable. It works, but it wears out too fast and jams up too much. My design takes care of it by starting from scratch and making it strong. My wife says I am strong like bull and smart like tree so I make everything I build that way. I also like to use whatever I have around the farm so that is exactly what I did. You could build it prettier and simpler, but recycling scrap is a priority around these parts, especially if you are broker than the ten commandments... This project really paid off for us, it just works great.

You need the picture of all the valve parts to see that it's easier to build than than it sounds let's GO...

I had a 2" to 1.5" copper reducer with a short piece of 1.5" pipe attached and that makes the valve body. I also had a 6" brass tail stock sink connector that I inverted and soldered inside the reducer because that had a nice smooth lip that makes a perfect valve seal with no work at all. If you have a new reducer and smooth it off with sand paper, you likely don't need the tail stock step but you do need a smooth edge for the valve seal to contact or else you will not get it working. Now drill minimum 2 (or 4 is better) 3/4" holes through the pipe just above the reducer and smooth the edges and presto, your exhaust port is all done.

Next problem... how to replace the O ring seal used in converted foot valves. It routinely wears out or slips out of place and stops your pump. So, let's not fool around. Take a hockey puck and use a hole saw to make it 1.85 " in diameter so it fits inside the 2" reducer and has lots of clearance around the outside. Drill a 1/2" inch hole exactly in the center and put a bolt and nut on it so you can hold it in your drill press. Then spin it with a file against the edge so you get a nice smooth beveled edge about 1/4" long. This presses up against the smooth tail stock lip to form your valve seal so make it as smooth and even as possible and it will work better.

Now get some plastic washers that slide easily inside the tail stock piece. I had a piece of scrap plastic around so I turned it on my lathe to fit. It works as a centering guide for your valve to keep it closing and opening in a straight line. (This is one reason other converted valves often fail.) The fit needs to be loose but not too sloppy, say 1/16" clearance.

Now make a top cap. I turned a scrap piece of aluminum so that it fit into the tail stock and had about 1/2" of overhang left at the top just like a cupboard knob. The half inch center hole is threaded to fit the rod, but you could just use a clearance hole and a couple of retaining nuts on the top and bottom. You need to be able to adjust the position of this cap up or down on the threaded rod as this is the regulator that controls the pump cycle frequency and efficiency. A giant wing nut would work too, just something to hold the valve stem assembly from falling out the bottom due to gravity when it cycles up and down.

Now assemble your valve. Put about 6 0z. of weight on the bottom of the threaded rod. (I drilled a 1/2" hole in a piece of scrap steel, (you could use heavy washers), just smaller diameter than the hockey puck which sits nicely flat against it. Put the puck on the rod then a washer on top about 1/2" smaller than the puck bevel then lock it in place hard with a retaining nut. (This valve cycles 2.5 times per second and receives lots of force (remember that water hammer discussion earlier, well, the hammer part is for real!) so lock it down strongly. This is another reason foot valve conversions fail as there is no way to stop the valve assembly from wobbling all over the valve body and it wears the stem or guide too quickly and frequently pops the foot valve O ring off the groove. That can't happen with my brute of a valve.)

Now put another retaining nut on the rod about 2" above the puck assembly. The valve cycles up and down about 1/2" so you want your plastic center guide to sit above the exhaust ports when it's all assembled and resting in the down position. Now put a retaining nut on top of the plastic center guide and tighten it down.

Almost there. Slide the finished valve stem assembly into the reducer so the threaded rod sticks out the top. Now spin on your top cap adjuster until it slides into the top of the tail stock and permits the valve assembly to move up and down about 1/2". Put a wing nut on top of the cap to hold it in place. You will have to loosen or tighten this cap a few turns at a time to make your pump operate optimally.

Step 3: Button It Up.

The hard part is over.

Now take the fire extinguisher and make a pressure tank out of it. You do that by screwing off the extinguisher handle and stuffing a recycled, deflated 20" bicycle tube inside the tank and then inflate it to about 5psi., that's it.

Next, assemble the pump like you see it in the parts list picture and lash it down to something strong or it will walk all over the woods. (remember that water hammer discussion earlier, well, the hammer part is for real!) so lock it down strongly, I used 4 x 3' fence bars bolted to a board and a 10" concrete block. I strapped the pump to that with copper plumbing straps and stainless screws. The feed water pipe is connected to the pump with a rubber plumbing connector.

Step 4: How It Works...

Here's how to operate it:

To run it, you need about 5' of feed water pipe for every 1' of fall below your pond or creek water surface. I have 10' of fall and 50' of feed pipe supplying 3 gallons/min. (A little longer would be better say 5.5:1)

Now manually push (cycle) the valve stem up and down about 30 or 40 times to fill the pressure tank. These pumps need back pressure in the tank to operate automatically. When the pump starts to cycle on it's own, you will want to screw the adjuster cap up or down to make the cycle frequency about 60 - 150 cycles per minute.

Experiment with the cycle frequency to find what delivers the most water for you. Lots of troubleshooting guides on the net to help you fine tune it. You may need to add or remove some weight off the bottom of the valve stem if it cycles too fast or slow and you don't have enough adjustment available by turning the upper valve cap. A little denial and error and you will find the sweet spot to get it running smoothly.

I have found that if it cycles too fast, it won't build up any pressure and the delivery flow is low or stops. If it cycles too slow, delivery flow is weaker and you use more feed water than necessary and you can drain the feed pipe if your supply water is limited. Mine seems to deliver the most water at a cycle rate of 150/minute.

Enjoy your gravity powered water pump, it's the closest thing you may ever see to perpetual motion... Hopefully you can see the movie of it working.

This is the best hobby project I have ever built from scrap parts and recycled junk. We use it every day all summer long and it facinates everyone who comes to visit us while saving real money!


GuyF19 made it!(author)2016-09-17

There is also another green water powered pump claiming to be the "Most Powerful Water Powered Pump in the World" on YouTube

DavidL237 made it!(author)2016-05-17

Thanks for your information!!

I have a small creek on the property, but it is at the lowest point as well. If there is only maybe a 1 foot drop - that wouldn't be able to pump up too far would it?

I ran across a water wheel (kind with the hose wrapped with the paddles to 'collect' the water). If that moved the water into a 55 gal barrel on a pedistal - then out of it to the ram pump - would that work?

eltigre made it!(author)2016-05-19

Your double pump suggestion could work but you would lose a lot of efficiency so you may not get a lot of volume at the destination point.
Not necessarily a problem if you can wait to use the water . just build yourself a water wagon like I did and let it fill up over night(s) then tow it where you need the water.

You may be better off using a water wheel to drive a piston pump which will raise water to a couple hundred feet above the source. Or you can drop a log across the creek and use the resulting damn to gain drive height. Run your drive pipe 60' downstream to gain even more height then drive a ram pump with that.

DavidL237 made it!(author)2016-05-19

Love that wagon!!

Not sure about the log -- the farmer that redid the crossover recently, put in two 24 inch culverts. Was just rocks... He also widened the down stream a little . When there were heavier rains, the creek upstream would overflow the bank and wash down the field (up stream about 1/4 mile). I might be able to do a one foot raise with a log... Another thought I had when I saw something to 'repurpose' was an orange caution cone (the kind you see by vehicles and drive lane guidance). Basically a funnel - would that help with pressure / fall? Attached is a look upstream.

eltigre made it!(author)2016-05-19

Not sure a funnel will help, you need height to create weight which drives the water hammer effect for a ram pump. Looks like you will be stuck with a water wheel piston pump or spiral pump or sling pump if your delivery point is not too far above or away from the creek. Let us know which solution you build :)

DavidL237 made it!(author)2016-05-19

Also - question... Do you really need the bike tire in the tank? Wouldn't the pressure automatically build up due to the hammer force?

In reference to the first question earlier - I do also have a large 275 gal tank - through a two stage system - first 'drop' fills the 275 gal tank that is raised (higher than the creek line), then empty that into another pump to send it up the hill...

Francis+PaulT made it!(author)2016-03-24

i uploaded the video of the flowing water beside our home. Its was dug by the local water supplier of the city and was abandoned when it deemed unable to supply the growing community.
Will this be useful in some other way? I want to ram pump this to better use

eltigre made it!(author)2016-03-25

Not likely enough flow rate for a ram pump. You might investigate a solar pump that moves water into a holding tank for use later when you have pumped enough to fill the tank.

Francis+PaulT made it!(author)2016-04-04

Oh man :/
That's just frustrating.
I get around 20 liters per minute by just catching water and putting it in a container using a dust pan. So probably more on actual. But like i said the hole is about 300+ ft deep. I want to use it for something.

SimeonB3 made it!(author)2016-02-11

This system looks brilliant. I have a natural stream flowing through my garden and I want to put trout in it but need more oxygen in the water. If I pressured the outflow so it squirted the water higher in the air, do you think this would improve the oxygen level and would you know how much it would increase it by (roughly)? Thanks, Sim.

eltigre made it!(author)2016-02-11

My ram pump was fed from my trout ponds and i did divert much of the flow out a 2mm nozzle up about 2m high and back into the ponds. The fish all seemed to like this arrangement. I'm sure it improved oxygen levels but I can't say how much. You might be better off to install a wind or solar power bubbler to aerate the ponds from the bottom up. In my experience, the water temperature is more important for trout, cooler is better, as long as you have flowing water moving through the ponds.

1nvent made it!(author)2016-01-09

I am contemplating building a ram pump. I have seen some that use an orifice below the check valve leading into the pressure tank. Do you know if this arrangement is less efficient than using an air bladder as in your design?

eltigre made it!(author)2016-01-11

The arrangement you describe is called a snifter valve. It's purpose is to suck in a bubble of air to maintain an air cushion inside the pressure tank. It squirts out a bit of pressurized water on each cycle before it sucks in the air bubble. Therefore, we can assume that a bladder inside the pressure tank is more efficient as it does not lose any of the pressurized water during operation. If only 1 ml. were lost on each cycle, with an operating rate of 100 cycles/min then 100 ml/min or 600ml/hr or 14.4 liters/day or over 5200 liters/year would be lost to snifter valve operations. Enough to notice I think.

Francis+PaulT made it!(author)2015-12-25

Good day and Merry Christmas to you and your family.

I'm very much interested with this project. When i saw this i tried researching and watching videos at youtube. I am actually looking for a way to utilize the free flowing water we have beside our house. Its a deep waterwell drilled by the local water company in our city but was abandoned. It's been free flowing for 40 years and we only use it to water plants or car wash. I've been thinking of a way to produce energy through the freeflow. So when i saw this i though i might pump the water up to a tank and drop it to make a generator or an alternator spin.

The well is 2feet wide and 150' deep and elevation from ground is about 4 or 5feet.

Im sure that 4feet is not enough to push the water high enough.

Any bright ideas you can suggest?

eltigre made it!(author)2015-12-28

Hi Francis,
You mention that your flow rate and volume is very low. In that case you are likely better off with a solar powered pump to move water to a holding tank to build up volume and pressure. From there you can drive a microhydro generator for short periods at high flow rates to charge batteries etc. but again, you won;t get something for nothing. A holding tank may be best used for watering etc. once its full but low volume = low power generation, no way around it .

Francis+PaulT made it!(author)2015-12-28

I see. I'll try collecting and measure the rate. I've tried to measure it before and it brings me a liter every 15seconds. By just trying to submerge a coke bottle :) of course a lot is still wasted and not counted

eltigre made it!(author)2015-12-27

Hi Francis. Thanks for stopping by.

4' of head is enough to run a ram pump and it will push water to 10x that height easily. Volume of water moved is contingent on the input flow rate. So, if you have 10 gal/min flow you will get a very decent delivery rate.

That said, why not use your flow to generate directly with a pelton wheel generator or other micro hydro generator project. A small universal motor or permanent magnet or brushless motor or larger stepper motor like from a washing machine or treadmill can be gear driven by your water flow at sufficient speed to generate 14 volts with no trouble. Water is heavy, use it to make electricity and shine on my friend.

Francis+PaulT made it!(author)2015-12-27

I'm sure the water flow is not enough to spin a pelton wheel. We've tried alternators and dryer motors. The flow just aint strong enough and does not have that much volume. I'm no engineer and does not have that much knowledge science related. Just someone who loves to make hobby projects. So i was thinking that if i can carry the water to a tank overhead and drop it to use that to spin a pelton. :)

I'll take a video and pictures of the area

BillyS21 made it!(author)2015-11-06

Does the head colum need to be straight, could it be in a tight corkscrew? In regards to working in a well? Great video , awesome job of sharing some tech.

eltigre made it!(author)2015-11-07

Does not need to be straight. Mine follows the contours of the slope but I'm not sure about a tight corkscrew. I would think that it should work for you as it's the weight of water the head column that drives the pump action. Let us know if you try it and it works or not.

dragonfire891 made it!(author)2015-10-26

Great job. Well done. Thank you for this design, it's just what I am looking for. If you have any ideas about increasing the water pressure on it, I would greatly appreciate it .. I am trying to design a combination pump and turbine DC generator. I really think it could be done.. Again thank you! Dave

eltigre made it!(author)2015-10-26

A higher head of water will increase your pressure

TravisM18 made it!(author)2015-09-30

So why not run the exhaust water through a couple of check valves into the air tank to increase air pressure using an ejector valve to add more air into the tank from the exhaust water jet while letting excess water go back into the water line from the air tank to increase pumping pressure?

eltigre made it!(author)2015-09-30

Interesting thought, but the pressure tank maintains a higher minimum pressure than the exhaust water so any check valve coupled to the exhaust ports feeding the tank would not open and with no place for the pressure to go, the pump cycle would stop.

you might be able to close couple a Pelton wheel generator to the exhaust and run some LEDs or charge up a few batteries.

TravisM18 made it!(author)2015-10-02

But you have to remember that narrowing the pip that the exhaust water goes through increases pressure.

You may need an air pressure valve to let out excess air if the pressures stopped the pumping action.

tiptip made it!(author)2015-09-25

CRMcG made it!(author)2015-08-20

Looks interesting but how's the efficiency? I've heard that the water loss through the second check-valve is around 90% thus the output is only 10%....


eltigre made it!(author)2015-08-20

Depends what efficiency you are looking at.

The COST efficiency is excellent. It uses no electricity, gas, diesel, solar, wind or muscle power to lift water. It is powered by a spring fed water source or any creek that flows at a rate of 3 gal/min or more. Therefore, my cost to lift water is only the capital spent to build the pump, in this case less than $100, and since it has lifted over 5 million gallons so far, my cost efficiency is 0.002 cent per gallon operating cost INCLUDING capital and gets cheaper with every gallon it pumps. Excluding capital costs, my cost to operate this pump is 0.00 per gallon. Compare that operating cost efficiency to a gasoline powered pump.

We don't say that a water wheel is inefficient because 99.999999% of the river that turns it passes by without having any effect on the wheel.

NicuR made it!(author)2015-08-18

Hello sir,

I have a technical question for you, if you would be kind enough to answer it.

Would it be possible with this method to pump water up the hill, having a distance of aprox. 900 feet and a level difference of about 500 feet.

Thank you,

water to the castle.jpg
eltigre made it!(author)2015-08-18

Hi NicuR,

Let's do a little math... water column pressure in lb/sq. in. is expressed as

Feet of height x 0.433 = Psi

so if you want to lift 500 feet in one pipe you will need to generate 500*0.433= 216.5 psi. Since this pump is capable of about 50 psi, you would be able to lift about 120 feet with a 3/4 in. plastic delivery pipe. In actual operation, I was lifting about 110' high over 700' distance with no trouble but if you go much higher then the delivery rate becomes very slow. To compensate, you will need a much bigger pump or install a series of pumps feeding each other about every 100 feet. The problem with that idea is that ram pumps deliver only a fraction of their drive water so again you will have little to no delivery at the top of the hill. You need a high pressure piston pump (maybe solar operated) or a number of them to run up the hill sequentially pumping from one holding tank to the next highest one.

den23m made it!(author)2015-07-24

how to install the bicycle inner tube inside the tank

eltigre made it!(author)2015-07-25

The tank is turned on/off via a pipe thread that originally sealed the fire extinguisher squeeze handle mechanism to the top of the tank. Before you screw the tank on to the pump, just deflate a bike inner tube all the way and you will have enough room to poke it into the tank with a finger or blunt end of a pen or a dowel or such, keeping the inflator valve for the last thing to go in. When the tube is all inside, just inflate to about 5lbs pressure and screw the tank on to the pipe.

A few years later I made an ABS tank out of a piece of 4" drain pipe and drilled a hole for the inflator valve so it was outside the tank and could be inflated once or twice a summer without shutting off the pump.

evyl00 made it!(author)2015-07-22

I am ready 2 start buildg aquaponics w/grow beds & want 2 use this ram in design. I need 2 know if "waste" water has enough force 2b redirected upwards back n2 tank. Supply @ bottom of tank, waste outside tank going back 2 tank, delivery going 2 grow bed (3ft or more each 4 delivery & waste)

eltigre made it!(author)2015-07-22

If I understand you correctly, you can't blow the waste water back into the tank it came from as gravity won't let you but you can put it into a different tank slightly above the valve exhaust port as the water exits with some force. This pump design needs a continuous head of water to operate. If you drain the supply tank, the pump will stop.

evyl00 made it!(author)2015-07-22

I actually just watched a YouTube of a guy from who actually submerged his ram pump & it still worked! This is doable! Everyone is actually lifting water a great deal of height/length though so I may need help figuring how to reduce the amount of water flow b/c I will be going from inside the tank to about 3' or so straight up into a pvc piping ring above the grow bed.

evyl00 made it!(author)2015-07-22

Well there is going to be a bell/siphon in the grow beds stationed above the 250 gal fish tank which will put the grow bed water back into the tank. I just need to devise a way to have the blow off or waste captured and returned instead of spilling on the ground. Using a capture bucket won't be feasible b/c I may not always be there to empty, hand pumps won't work because that kind of defeats the whole purpose. I will have to think on this. Thanks for the quick reply! If you have any other thoughts to share, any help would be greatly appreciated!

cheesewhiz14 made it!(author)2015-06-28

can we buy a set of instructions for this?

grijze made it!(author)2015-07-10

something like this?

eltigre made it!(author)2015-06-29

I don't have a detailed set of plans but the info above should be enough to get you there. try it and let me know if you have problems and I will talk you through your build.

ldscaper made it!(author)2015-07-06

Have you tried to lift water from a well? Do you know how many feet it can lift? Ever consider selling one? I like the old school technology!

eltigre made it!(author)2015-07-06

This design needs a head( height difference) of water to create a water hammer needed for operation. Unless you can think of how to make water flow inside the standing column of well water this design can't operate there.

I did see an old patent that claimed it had a ram pump design that worked in a well but I never investigated it.

eltigre made it!(author)2013-01-23

You could use high pressure pvc. My experiments with plastic did not go well because the constant pressure surges caused the abs fittings to burst after a few weeks. maybe if you are using a small diameter pipe like under 2" it will work for you. There are many designs on the web that show plastic pump bodies. I never had a problem with bursting after I built the pump body out of steel fittings.

You can definitely run the outflow back to the pond surface for agitation purposes. If the outflow is directed through a smaller diameter nozzle, it will spray quite far. I got at least 20 feet out of a 0.25" nozzle. You may get even farther out of a smaller diameter nozzle.

charlessenf-gm made it!(author)2015-05-20

"You could use high pressure pvc.... the abs fittings ..."

Were you mixing ABS (fittings) with PVC (pipe)?

I thought they were incompatible.

eltigre made it!(author)2015-05-20

No, I only used abs pipe which connected to a steel "T". I suggested that you might have better luck with high pressure pvc.

JordanR6 made it!(author)2015-04-05


Do youknow if these kind of hydraulic ram pumps would be full submersible? I am wanting to build a pond with a waterfall and small stream that is self contained. My idea would be to place the intake at the far end of the pond leading to the ram pump at the other end of the pond. I am wanting it fully submerged so the water loss isn't an issue for maintaining the pond's water level.
Do you know if that would cause any sort of pressure issues?


TomP14 made it!(author)2015-05-07

You can't put the water from the exhaust back into the same reservoir it came from. It has to flow down hill to create the energy to drive the pump.

drew.stevenson.714 made it!(author)2015-01-06

Thank's for getting back to me so soon. I Like your site very much.I believe I may be able to salvage my old waste valve and create a new base out of material i have in my boneyard. The Pond has an old air box that was used to regulate water level. It has a 12 in pipe that drains at the base of the embankment equal to 10 ft of head. I have sealed the drain because the old stand pipe or box has rotten away at base. I have been pondering if it would be possible to create a waste valve that would connect to the 12 inch pipe that then would connect to a fabricated steel air box with a bladder a threaded delivery line at 6 inch. I will try to send a sketch. Again great site and thanks for any advice.

eltigre made it!(author)2015-01-06

I'm not sure how large your waste valve is, but if it's anything 4" or under, you may be faster and cheaper just to run a new feed line out of ABS drain pipe. I used 50' of 2" ABS as a feed line connected to the pump with a rubber coupling covered with a stainless clamp. like this:
and it worked fine for years. No fabricating & easy to take on & off. I imagine you could go up to 4" this way pretty cheaply but you might start to have trouble with the coupling leaking pressure at that diameter so you may need a threaded union joint for greater strength... like this:
Post a sketch or link to tinycad drawing so we can see what you are thinking.

eltigre made it!(author)2015-01-06

Hi Drew,

I see no reason you can't scale up my impulse valve design to whatever size you need and bolt it to whatever ram pump body you prefer. I turned down a 2" hockey puck for my 1.5" valve size but you could buy bigger chunks of rubber or polymer than a puck. Something like a boat roller guide might serve you. e.g.

The best advice is to make sure the valve stem runs up and down smoothly and centered. Do that by attaching at least 2 centering guides made of plastic. You could cut them out of sheets of 1/2" or thicker polyethelyene or buy some nylon casters of the correct size to act as centering guides so the valve stem must stay aligned to the valve seat.

Post a sketch if you like & I will comment on it for you. you might like the free CAD program here:

to help you design something.

drew.stevenson.714 made it!(author)2015-01-05

Hello. I have used a ram pump from folk ram pumps. It was an aluminum cast body which over the years has broken. I was able to make a new bell housing out of eight inch well casing i had however the aluminum cast waste valve assembly has also gone the way of the body. I am now without a pump. The pond that i am using is 4 acre ft I have 8 ft of head and have a 3inch feed pipe in place with a flow rate of 200 gal a minute i would like to manufacture my own pump and would greatly appreciate any help or advice you could offer.

About This Instructable




Bio: Inventing (and breaking stuff to see how it works) since before the turn of the century...
More by eltigre:~ 1 Step Belt Holder ~~ Pro Footrest from Salvaged Materials ~~ Recycled Shop Storage Solutions ~
Add instructable to: