Thursday, April 16, 2015

Water Water Everywhere? Dual Feed Pump

Water water everywhere but not in my pump dual feeding the power washer pump, more flow to the pump-head.

I ran into a situation this week where my pump could just keep up with the surface cleaner, hose running up hill and having to park to far away, thus using a lot of high-pressure hose. The pump kept having cavitation issues, thus it was water starving. Trying to draw in more water to the pump, for the needed demand was more than the one existing line could draw. I was able to use the water feed from the home owner and supply the needed demand this time. So I mad up my mind to feed both sides of the pump with 1" inside diameter lines. 

Starving the pump from water leads to heat build up and heat is a killer of pumps.  Since the water also removes the heat keeping it cooler. Water also lubricants the pistons in the seals and head reducing friction and helps enable the pump to form the the "water-seal" that makes it help form the pressure and compress the water. Keeping water in volume in each cylinder becomes very important to the live and function of your pump. If the first two cylinders are drawing more water the last one will starve. So by dual feeding the pump you reduce that risk and have more water available which can now enter from both sides. Also should make it easier to draw water in reducing any starving or heating issues. Now that you know some of the whys of doing this here is a pictorial guide-line of what I did and what I used

List of parts:
angle head grinder
hand tools
Teflon tape
2.  1/2" brass 45* fittings
PVC Flex Pipe
PVC fitting to match the PVC Flex Pipe you decide to use
PVC glue and primer
roll of tin-foil
propane torch or heat source
Sharpie marker
safety glasses
wet towels
standard PVC cutter came in very handy

then with luck and due diligence you jump in & hope for the best

I started off with the intention of using 1 1/4" feed lines but due to the fact I could not locally obtain the needed fitting I went down to one inch lines. The second problem is the unit I was going to do this one is a belt driven Mi-T-M and as with some belt driven models the plug to feed the inboard port is blocked by the belt cover. I also ran into the problem of with such tight bends in the tubing it may kink and not let the water draw free and easy to the pump. With the help of the clerk at Nixa Hardware we can up with using "Flex PVC Pipe" not tubing but flexible, glueable, formable. thick walled "pipe". I had never heard of this or seen it before. What made it even more useful was that it glues to any standard secdual 40 PVC fittings. Both the "ID" and the "OD" of this pipe fits and can receive the PVC fittings. I found out with the right amount of heat the PVC Flex Pipe can be coaxed to bend a bit more then when cooled it retains the shape. I used the standard PVC (purple) primer and the standard PVC glue to insure the fitting would not leak. 
Flex PVC Pipe

With some standard tools and a angle head grinder I was able to make this idea come into being. This is what I did I hope it helps.

 Photos of my progress on this project:

Great picture of my first intention of dual feeding this pressure washer. As with all good intentions this one had some problems which worked out even better finding some new products as the "PVC Flex Pipe" which made the installation even better when finished.

Dual feed pressure washer pump set-up notches in both the backing plate and the belt cover allowed me to replace the plugged water feed on the inboard side of the pump with a new fitting allow to dual feed the pump.

In order to make this cut I removed the belts and large pump pulley to cut into the back cover it was also done with the blade on the angle-head grinder. All opening were plugged in the pump than covered with tinfoil to keep any grinding dust out of things. Wet towels were placed over the motor to keep sparks and dust from it also. Always safety first. You still see I have plenty of clearance to adjust the belt and move the pump forward.


Laying out the shape and design of the notch in the belt cover with a Sharpie then cutting it with a angle-head grinder a little at a time I came up with this shape and with a slight bent allowed it to be taken off and replaced with not problems

I had the notch made in the belt cover and the backing plate all set up for installation of the 1 1/4" spa and pool hose but fitting it to the bulk-head became a problem. so I went with the set-up below. Local suppliers did not have what I was wanting to use and I was in need of the pump the next day.

You can now see I have replaced the 1 1/4 inch brass fittings with brass and PVC secudal 40 fittings. They still fit through the notch made in the back plate of the belt cover which enabled me to do this addition.


Using brass 45* fittings off the pump helped with the clearance issues. Brass fittings have a much larger inside opening than those made for cast steel. While brass may be more fragile it will supply the water demands better. The flex pipe can still take a lot of shock and vibration out of the system.

With some heat I could form the PVC Flex Pipe to make these sharp turns. You can see where the purple primer has cleaned the PVC fitting and I then glued it up making it a water-tight permanent bond.

The dual feed pump head checked out and met the needs pumping out over 5 gallons a minute.
I used a fine brass screened filter inside my tank to keep out any depree from entering the pump. I also filter the water supply before it enters the tanks float valve. This screen is like my older Landa skid system it filters what may fall in to the tank when the lid is off.
Cleaned by Pete
just a power washer in Springfield MO

2 comments:

  1. Absolutely nice blog i like it Deferentially this blog have this quality big cost, special effects, thank for sharing nice post.

    ReplyDelete
  2. The really cool thing is that the extension has a 1/4 inch quick connect fitting on one end so nozzles can be changed easily. That means I can get something like this Bellevue Pressure Washers

    ReplyDelete