I bought a new softwash setup With intentions on getting 10gpm. I’m getting about 3. I have a dual diaphragm flojet pump with a 9.9 cfm compressor. I am running 5/8 hose. Any suggestions why I am not getting any more gpm?
What’s the gpm at the pump?
By “at the pump”, do you mean like straight out of the pump. I haven’t actually measured gpm’s there straight out of the pump. Only at the end of my 200 ft of 5/8’s line. Would I lose that much gpm with friction loss?
And I am measuring gpm’s with the old bucket method, and not with an actual gauge. 
still accurate though right? Lol
Yes, at the pump. If you are getting ten there and three at the gun then you have a lot of friction loss. You got a hot mess of plumbing going on there on the air pump and the pressure washer
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When you think of plumbing next time think circle not square. Golden rule.
Hey Hustle, what’s that mean?
Gotcha, I’ll try that and get back to you. I actually thought my plumbing was pretty simple. This is also my first build so I also “thought” a lot of stuff that didn’t work lol
Fluid Likes the path of least resistance, 90 degree elbows work against it. Count how many 90 degree turns you have from the inlet to the outlet. It’s one thing to build it nice, tight and compact unit but you also need to think plumbing. Sometimes a messy looking setup is the most efficient.
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How much of that 200’ of flexzilla is still on the reel when you’re testing it?
Have you tested it without the mixing valve setup?
No, I just got it all set up and tested it for the first time. It was ALL on the reel. Maybe 5 feet off for me to test it. I Didn’t think it would make a difference. What is the best way to test it for the best accuracy
I’d do what IBS said first and test straight out of the pump. Then go forward from there until you nail down your restrictions. I asked about the flexzilla because it will compress around the reel and give you less flow than if it’s all off. You might have a bunch of things stacking up against you, each taking their cut of your 10gpm
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Yea, I’ll give it a try tomorrow. When I first start to spray it has good flow pressure, but after about 10 seconds the flow pressure is not nearly as hard. The PSI on the regulator when I start to flow is about 140 and after flowing at stays around 100psi. I feel 100 PSI should still be plenty sufficient though for good gpm flow though. After the diaphragm pump there are only 2 - 90’s. One coming out of the pump and the other at the reel. There is about 3 feet of hose between the pump and the reel. I’ll try straight out of the pump tomorrow and let y’all know.
This whole design just isn’t efficient, you could be suggested 50 different things but it all starts with the fundamentals being semi accurate in order to find other things wrong. For starters proportioners are a suction system witch should be plumbed from the top of the tank for even draw rate witch I think you have done but the elbows at the top don’t have to be there that part could be just a piece of hose going straight into the tank from above. Your second restriction is the ball valve, get rid of it you don’t need a ball valve there. The other thing I see wrong is an air leak being your soap nipple up top what’s going on there. And raise that pump or lower your proportioners that clear tube is giving my OCD disorder a hard time lol.
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I’ve seen other guys using a 7GPM flojet and 5.5CFM compressor say they bumped their PSI up to 115. Not first hand experience just what I’ve read when looking into air diaphragm setups.
Check the sight glass on your compressor pump looks like you have very little oil in it, just something to check
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Hey, thank you for the input. I’m going to change the 90’s at the top of the proportioner to straight barb adapters. Good call. I do have it plumbed into the top of each tank too btw. I’m not sure what ball valve you are talking about. The blue ball vales you are seeing runs are both on the same 2” discharge from the bottom of my water tank. One shuts the water off from the buffer tank to the PW, and the other is a drain. The middle 1/4 barb on the proportioner will be for the surfactant but since I wasn’t flowing it I didn’t think it mattered if the hose was on. I guess it’s an unfair test to check GPMs if I don’t have it all hooked together. Another good call. Also gonna do like IBS said, and I will test straight from the pump after I make these few changes. I’ll report back. Thanks everyone.
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So… still not working. I changed the 90’s and even unhooked the proportioner and tried running the pump straight to the tank. I unhooked from the reel and ran from the pump straight to a bucket. I got about 6gpm. But… its pulsating hard. Like sputtering. Sputtering hard enough where the hose was jumping all over the place. I was able to turn the pressure down to about 40psi and got a good steady flow but only about 3 or 4 gpm. When I turned the psi back up it started sputtering and jumping all over again. What’s y’all thoughts?
