Forced downstream injector with shurflo 5.3gpm pump

Hey all Sean here the new guy! I began soft washing in the spring and for the last nine months I have been heavily researching the best ways to do soft washing with a pressure washer. I have been told by many that I cannot have a strong enough mix downstreaming to do roofs or hard flat surfaces. I recently upgraded from a 5 to an 8 gallon per minute machine. When I started with the 5gpm machine I was using a super sud sucker from Envirospec with the 2 to 3 gallon per minute nozzle. When I hooked up a 5.3 gallons per minute 12 V pump to force feed the downstream injector and I could empty a 5 gallon bucket of SH into the line in a matter of a few minutes.

I upgraded to an 8 gallon per minute machine and noticed when using my bypass that the 2 to 3 gallon per minute nozzle gave me a very small flow of soap no different than it was with the 5 gallon a minute machine (obviously I could have a 1000 gallon per minute machine and the size of that 2 to 3 gallon per minute nozzle would only let so much water through.)

Originally my thought was to use the two gun feature and each have their own down streamer so that we could soap twice as fast and then just switch to one gun and rinse at 8 gallons per minute. However that would defeat the purpose of being able to shoot up an extra 10 feet with my new bigger X jet. Yesterday I upgraded to the 5 to 8 gpm nozzle in my injector. I noticed a substantial increase in flow when bypass was turned to spray chem.

Nobody seems to know about adding a pump to force feed the injector. Is there something wrong with doing that? Now that I have 8 gallons per minute using the pump is a must to get enough soap on the wall with that bigger nozzle.

My plan to be able to do roofs and flat work would be to swap out the super sud sucker with the 5 to 8 gallon per minute nozzle for another one prefitted with a 2-3gpm nozzle and run it with the pump. This will give me substantial amounts of SH compared to the amount of water running through it. So to reiterate my question is how come no one seems to force feed or downstream injector or the pump to get a hotter mix?

Your 12v will go out prematurely because of cycling and your high pressure hoses aren’t designed to handle that hot of a mix. You would be better off setting up that 12v with a dedicated hose and a porportioner. I do have a 1.8gpm 12v that I force feed with to post treat concrete on larger jobs. The 1.8 is disposable since it’s so cheap. Be sure to flush it out or it won’t last a week of heavy use. I’m fairly new myself but this is my understanding of it.

Where you located @Seandz


I do flush after every job with final wash which is supposed to neutralize the SH. I’ve only run the pump a handful of times but now plan on mixing half and half water/sh and using the pump so I can get at least 1% for house wash since it’s going through a 5-8gpm nozzle.

Good advice though I was thinking there had to be a reason people don’t do it/talk about it. Appreciate the feedback!

Also was told that this pump has a bypass but what I do is (until the remote is set up) make sure to turn the pump off right away when done spraying

One other thing, I found a manufacture of high-pressure ball valves that make 3000 PSI rated 12 volt electronic controlled high pressure ball valves. My plan is to get one of those and hook it up to another remote control and use it in my bypass. This way I can rinse and switch back-and-forth to soap without having to run back to the truck every 10 minutes. Anyone using one like that?

If I’m understanding your correctly, I do. Save yourself some time and get with @SchertzServicesLLC with one of his remote systems. Bullet Prooof. Sure you can make it yourself but your time would be better spent working and acquiring jobs. My 2 cents.


Does his just turn the soap tube valve on and off or turn the bypass on and off? Really want that full rinse power…

His does both. No loss of gpm

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Does he have an online store? Could you send a link for it? Googled it and didn’t find anything regarding products. I’ll buy it tonight! Thank you!

He will pop up in the post I’m sure. Long time member and expert tinkerer. Search: Schertz remote. He makes two versions. You want the 3-way version for max flow.

Nope uh uh :smirk: Mine have no remote though, pull the trigger you’re in soap, let go and pull it again now you’re in rinse.

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They do make 12v pumps that don’t use a pressure switch and don’t need to cycle. They bypass internally and are rated for continuous duty. I run the Shurflo 5059’s with a heat sink


Nice. Thanks for the info.

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I was told by Envirospec the shurflo pump I bought would work for continuous duty as it had a bypass.

The only thing I don’t understand is when I’m not downstreaming no fluid is moving so how could that be a bypass?

Yes fluid is moving it’s just moving inside of the head. It bypasses inside of the head as in the fluid just goes round and round bypassing the outlet once up to pressure it would not externally bypass to another tank


What’s the price tag on that pump?

The one I bought I believe was $280. Unless you were asking DPerez his looks cooler than mine with the heat sinks!

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How many GPM ? @Seandz
Never mind , 5.3 gpm. My bad