For those that have a 12 volt pump to boost the chemical into your chemical injector what gpm 12 volt pump are you using?
Is this what you’re looking for?
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I think he’s talking about using a 12V to force chemicals into a downstream injector, so that you get a stronger percentage coming out of the gun. I’ve read about people doing it, but i’ve never tried it.
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Yes that’s what I’m asking.Sometimes on a really bad driveway downstreaming isn’t strong enough,just looking for a faster way instead of dragging out my roof setup just to spray a driveway.
Xjet…
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Is there a way to gut this injector sucessfully so that I can quick a 2.1 injector on there ? I tried to quick connect it without gutting the factory one and it wasn’t drawing soap because of the back pressure or something like that from the original injector design inside. When I looked inside to take it apart. The guts of the injector is almost designed so that it redirects the back pressure to a small hole for the unloader to unload the water back through the pump. The reason I want to gut it is because the stainless steel ball was lost, the spring was toast, they discontinued making that specific spring for the built in injector and I’m seeing options before I buy a new pump without an unloader or injector built into it. I tried swapping the spring and ball from the 2.1 but the ball is a different size. So… any help?
You might be able to drill it out carefully. 
Take my advice and take the plunge now and replace the pump. Don’t put any labour into that pump. your just postponing the inevitable for no gain other than curiosity.
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What motor is that? Horsepower rating?
Its a Honda GX390 Commercial Series Engine and the pump is a Industrial 4.0 GPM Triplex Plunger Pump. Wanna know the sad part? They discontinued my pressure washer and so parts are scarce now. Can’t even get the spring that goes in the dang injector. It’s a DXPW4240 model
Oh man you are way ahead of the curve then. Gear drive 4 or 5.5, unloader, skid and you’re set!
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It’s direct drive not gear so, I gotta find a pump that matches that doesn’t have a built in chem injector. I don’t really care if the unloader is built in or not on a replacement pump because once I got the money for the enclosed trailer and pressure pro 8gpm 3500 psi hot skid, Ill plum that to a tank and wash with that! I’ll keep the 4.0 4200 as a backup. Then eventually build my softwash system that’s similar to the fat boy and be setup for roofs and soft washes for siding!
No no, you can slap on a gear drive to your GX390. Seriously. It’ll pull water from a tank too.
Here’s an example.
Any recommendations for a pump? 3500
Psi and as much GPM as I can get ! Without a built in injector please 
I’m still researching
Well here’s the issue, you have about 13hp with that motor. You can do a 4gpm/3500, which is…meh.
Or you can get a 5.5gpm/2500psi if you don’t plan to do much concrete. It’ll be a housewashing beast. The other veterans on here can explain in better detail.
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I do a good amount of concrete lol. Honestly might just replace with the same specs
Here is the inside of the injector and you can see how it’s right off the unloader, do you think if I just remove the whole piece that’s still attached to the quick connect and find a connection that allows me to go off the open hole next to the unloader straight to the quick connect that it will work? I don’t wanna actually try this as I don’t know how the back pressure without these pieces in it will effect it. The piece could just be for the chem injector but I’m not sure
Allz I know is ZGR > YGR
Not trying to be a…richard…but as I went through the same thing as you in 2018, save yourself the hassle and just get another pump with separate unloader. Don’t even bother trying to mess with that.
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