The Ram Water Pump, a low cost solution
2014 Several years ago, my brother-in-law made the comment that some time ago, people used to have a way to pump water without electricity. I didn't know what he was talking about, and I didn't think much about it at the time; then one day, I needed to pump water from my creek. Well, not just like that; I had trenched in a water and electric line 300-feet down the 30-foot hill to my creek so I could put a pump down there and use that water source. But, the creek was so shallow that my pump sucked to much sand all the time and the pump didn't work out. Still needing water from the creek, I remembered what my brother-in-law had said and I began to research it. Low-and-behold, the Ram pump came to life, and does it ever work good.
2016 Ram Update: I put the Ram pump in the creek for the season yesterday, 3/27/16. This begins the third year using the same exact pump pictured. It wasn't in the creek long before the original impetus valve failed. A spring check valve isn't really good enough therefore I replaced it with a 2-inch swing check valve which was a great improvement. Increasing the size of the impetus valve improved flow a good deal. This pump puts out way more water than I can use, so though I wanted to increase the size just for fun, I don't think I will since I don't have a need for the excess water. Last year I put a water tank at the pig area near the creek, and this year I added an overflow to that from the ram pump so the pigs have a constant pool of fresh water to play in. I did make another minor change last year to prevent the occasional waterlogging of the pressure chamger; I drilled a small snifter hole below the plastic check valve. I used the pump all last year without any waterlogging problems.
Now that the third year of experience with the Ram Pump has rolled around, I have some important updates with regard to some of the claims and statments I have seen on the internet and youtube. They are listed below.
- The drive pipe needs to be steel - False: Plastic is cheaper, use it! I made mine using 80-feet of 1½-inch PVC, and it is going into its third year with no problems. PVC is cheap and flexible making it easy to follow the curves of a creek. Of the issues I've had with my pump over the last three years, the drive pipe hasn't been one.
- The valves need to be steel or brass - False: No they don't, PVC works just fine, but I did use some steel fittings for the main support and brass for the impetus valve. I have not yet tried a PVC impetus valve, but I may at some time in the future. One thing I have learned though is that it is beneficial to have valves one size larger than the drive pipe, and the weight of the impetus valve flapper is important if using anything other than a steel or brass swing type.
- The valves need to be the same size as the drive pipe - False: Valves tend to be a bit smaller than their size spec so I always like to go up a size with valves whenever I can so as to eliminate a flow choke. I did the same thing with the ram pump, and it has worked very well. See flow update below.
What about a snifter? - This is an important and often overlooked part on some of the backyard Rams being built. The snifter can simply be a very small (1/16-inch) hole drilled immediately below the delivery valve, and does not need anything else in it though some people do fabricate some sort of valve. The snifter hole or valve allows a small bubble of air to rise through the delivery valve into the pressure chamber preventing waterlogging which will definately occur unless you are using an air filled bladder. Waterlogging always occurs on any water system using any sort of pressure tank without an air filled bladder.
When I first built my pump, I didn't have a snifter hole, and of course experienced water logging as you will. With the snifter hole, I don't think you would need a noodle or bladder of any king, I will update that later.
- The pump is not adjustable once made - False: The pump can be adjusted somewhat by adding or removing weights from the impetus valve flapper. If you're using a PVC valve, the flapper will be way to light. You can correct this by drilling a hole through the flapper and put a bolt through it with washers or nuts as weight. This same technique works for other check valves as well. The longer the delay in the valve closing the larger the volume of water pushed back through the delivery valve. It's a balance though; if you have to much weight, the valve won't close or may hang open from time-to-time. If the weight is to light, you are losing efficiency. A rapidly closing light valve won't pump near as much water as a properly weighted valve.
- It's costly - False: Don't spend a penny more than you have to, PVC works just fine and I think if it were braced with any reason at all, the pump could be 100% PVC. If my pump ever breaks, I might experiment with this.
Pressure Chamber - I had read on the internet that the pressure chamber needed to be at least 4-inches diameter and 4-feet long. I only had a 3-inch pipe when I built this pump, and the 3 x 32 chamber has proven to be quite adequate debunking the 4 x 48 claim. I think it could even be much shorter without decreasing efficiency with a snifter.
I used a 3 x 32-inch PVC chamber with a swimming noodle inside at full length. Some people have said that the noodle needs to be half length, but I disagree. The noodle is hollow and compresses significantly so if used it really needs to be full length. I don't think a noodle is needed at all if a snifter is used.
Another important issue with the pressure chamber is sealing of the top. I read that you can't use a threaded top, but I did. It did leak and caused waterlogging but once it sealed it was fine. I wouldn't use a threaded cap again because if you get it tight enough not to leak, you won't get it off again.
- Drive pipe inlet filter - You need it! Don't spend any money on this, it's easy to make. I used a 30-inch piece of 1½-inch PVC pipe which I did not glue to the coupler, and I drilled several rows of 3/16-inch holes (¾-inch spacing) which prevent anything of size from flowing down the pipe. I tried smaller holes at first, but they plugged up from time-to-time; the larger holes don't. I never remove the drive pipe nor the filter extension from the creek during the winter though I often have to shovel the sand and debris from around the filter pipe in the spring. I leave the pipe open for a few minutes to flush out before connecting the Ram Pump in the spring, or hold the impetus flapper open until the pipe runs clear during the summer.
I pump the water from the creek over to my pigs with a total rise of 12-feet where I get 1.6-gallons per minute of water flow (2,304-gallons every 24-hours). Sometimes I pump the water to my barn where we also have a living area and which is 300-feet up a hill. I was getting a gallon of water every 2.4-minutes (600-gallons every 24-hours), but I haven't yet measured that flow since the impetus valve replacement.
2016 Flow Update: The 1½-inch (impetus) check valve that I had on the pump finally failed to the point where I decided to replace it (4/4/16). I replaced this with a 2-inch swing check valve which seems to be significantly more reliable. The flow increased from .83-gallons per minute at the pig tank to 1.6-gallons per minute which was much more than I had expected.
When I built the Ram pump, I put an 8-inch pressure treated dam in the creek for my trial run two-years ago, and spent less than $150 on the whole job. It is my plan to pour a 24-inch high concrete dam in the creek this year with a flush gate at the bottom, and with a 3-inch Ram pump outlet on the top for a larger inlet capacity should I decide to increase the drive pipe size. This will also give me another 16-inches height in the drive pipe. I hope to increase the pipe size to the barn from ½-inch to 1-inch for better flow at the barn when I need it there. Raising the pipe 16-inches at the dam will also result in a 21% increase in the head, which will in turn increase the efficiency of the Ram pump.
My workings with the Ram pump are purely experimental, mostly in an attempt to learn what will work, and how cheaply it can be accomplished with reasonable reliability. I will keep this site updated as my Ram Pump evolves with the changes that I make and the resulting water flow rates.
Problems experienced to-Date
- Impetus Valve - This has been the most problematic part of the pump so far though minimal for the most part.
- I have found that the valve being one size larger than the pipe is beneficial.
- Though just about any check valve can be made to work, the use of a swing check valve greatly improves reliablity and a brass or steel valve is weighted just about perfectly as they come.
- The inlet filter - An inlet filter of some kind is necessary. A 1½-inch piece of PVC capped and 30-inches long with rows of holes spaced +/- ¾-inch apart and 3/16-inch holes drilled ¾-inch apart makes a great filter. I also drilled many holes around the cap and in the end of the cap. I didn't glue the filter into the attaching coupler which makes removal for cleaning easy if needed. I cleaned mine once in three years of use since it's pretty much self cleaning. Smaller holes get plugged to easy, and larger holes let to much trash through.