Dewalt 4gpm/4400psi with a built in injector but I’m using secondary 2.1 injector. I was having trouble today pulling anything with the higher pressure soap nozzle on my Jrod using 100 ft of hose.
Yes, I’m running the DeWalt with the GX270 and the AAA 3.5/4,000
Original injector is still intact, unmodified, uncapped and was in working order a few years ago before I swapped to the GP Hi-draw.
And you have no leaks anywhere in the system right?
Was this your two matching hoses? Or two unmatching hoses?
If your original injector is still on and uncapped, try holding your finger over it or placing a piece of tape over it while trying to draw soap and see if that makes a difference.
Didn’t have time to test the different hoses today just had to jump into it but I’m going to. Someone link me the exact 1.8 injector I should get so I know I don’t go wrong.
I gotta admit, I’m amazed. Seems like every one I’ve seen with those small rigs has an issue with the factory one so early on that they have to gut it or cap it and run the secondary. If yours is still intact and uncapped, do you still have any suction at the factory one’s nipple?
Using the 2.1 GP High Draw 3-5 gpm on my 4/4k rig I can pull soap through 450 feet of hose & the flow is better than a 1.8. Also, if you use the J rod pressure tips to disable soap, they still draw a little… especially if the injector is undersized. Always keep a back up injector or three & be ready to swap them out in a pinch.
Your 2.1, is it a GP High Draw or something else?
I’m afraid I can’t recall ever actually putting my finger over the old injector to see if it’s still trying to pull. It never caused an issue so I just let it be.
I was warned about the likely-ness that I would have to cap it though when I first started. Just never came to it.
The venturi that causes the injector to draw takes place where the restriction is eliminated, so only the last one will draw. On the side note, I started out using a pump with a built in injector that I had capped off & then ‘upgraded’ to another 4 gpm without the injector built in. Zero difference in performance.
There shouldn’t be any restriction on an open nipple. The venturi just comes from the fluid passing over a port creating a vacuum. If there’s no cap or anything on it then I would think it would at least suck air.
My factory injector didn’t have any suction when I tested it.
There should be a rule here that if you have a machine with a built in injector you can’t post.
That would be encouragement to get real equipment.
Sumn wrong somewhere i got aaa pump on my 4gpm never capped off injector and got 200ft hose and pulls fine on 2.1 
Don’t be jealous that us simpletons can still get some projects done with these smaller machines and still have time to drink a few cheerwines at the end of the day! 
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Pretty much. A carburetor works the same way. A venturi introduces restriction in the flow so water, air, whatever passes through the restriction has to speed up as it passes through. Where the restriction is removed, it creates a low pressure area. That low pressure area is where the carb draws in fuel, or the injector draws in soap.
You’re not a simpleton. But it would cut out a lot of senseless chatter if everyone just got real equipment to work work. Win win for everyone.
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You mean Udor can’t throw in an injector?? Haha, but I totally get where you’re coming from.
Might be a few days old but have you cleaned the injector and check the spring and ball make sure it isnt getting stuck ? Or uding the right tips to draw
