Downstream Injector Test. Honda gx390 with CAT 67dx39g11 pump
easily makes 4000 psi with trigger pulled…motor barely grunts…but I should get another guage to verify pressure. Good running machine.
Ok, I am editing and checking Math.
Old 2.1 injector. 1:44 to pull 1 gal from bucket
New 1.8 injector. 1:45 to pull 1 gal
New 2.1 injector. 1:42 to pull 1 gal
Moved 2.1 to before gun. 1:40 to pull 1 gal NO ADVANTAGE
According to the CAT pump manual, the factory injector is 2.1mm and also rated at 76.8oz/min.
thats about 15% draw as well, if my math is correct.
Xjet 33 sec to pull 1 gal! That thing PULLS Strong.
All testing done with 50ft hose.
3.9gpm x 1:45= 6.825gal
So…1gal/6.825gal=0.1465.
Or 14.6% 14.6% DRAW.
So.I am thinking…6% straight household bleach x 0.1465= 0.87 % on wall?
I have run about 3% through that injector before, and it did remove mild algae-moss-green crap…and thats 0.43% on the wall, but I did have to touch up some places sometimes.
These GP HI-Draw injectors arent any better than the factory cat unit. I would like to know if Anyone has verified a Better Injector, or higher Draw injector.
Great work! Everyone should take the time to do this with their setup.
You’ll never know the exact % of SH hitting the siding, due to manufacturing differences and chemical breakdown over time. But at least knowing what variables affect your pull ratios, will enable you to make more informed decisions day to day.
A half hour’s worth of timed trials was an integral factor in the success of my largest project in 2019.
Put 20025 tips in 18 inch rigid surface cleaner, still held 3500 psi
Surprised. Cleans good, maybe better with original tips.(2002)…unsure.
Need better gauge…25 dollar clunkers …
@mustang don’t get too caught up on the 0.1 measurements of mixing sh, that amount of precision isn’t physically possible, too many changing variables. Those that claim to fine tune to that degree have rocks between there ears and don’t understand the fundamentals of reality. Start with a start with a weak mix and add more bleach as you see fit.
@squidskc has a post about the proportion injectors that pretty awesome. You can dial in you draw to DS straight SH with your preferred surfactant. They’re stainless with ceramic balls, hastelloy springs, and good O rings. Check that out for your draw rates
I get about 9-1 with my 4gpm machine using m5ds nozzle and right at 18-1 with my 8.5 machine using 2.1 injector Running straight SH with surfactant thru the 4gpm I’m hitting the wall with about 1.2% net. That’ll clean just about anything.
So just run a stronger mix. With my 4, I’d run about 70% SH, rest water and that’ll clean most homes.
You can buy screw in proportioners for for the gp injectors. I have one setup where I can pull almost 12-1 with the 8.5 but I rarely need.
What are you guys using on your fittings, to keep them lubed? I used some synthetic chain lube …it did great on the actual fitting, but it seems it swelled the orings in 2 fittings…so I guess thats a No NO.
@Mustang save that lube for the fun stuff or your bicycle and use a proper silicone based oil for your O-rings. My favourite is a brand called 3-in-one. Works great
No, because stuff like that is irrelevant. Orings are a nickel each. Replace them when they leak. There is no reason to ever spray lube or anything on fittings, couplers, orings.
For the new guys. Disregard this ridiculous comment. Use silicone grease or oil on your qc’s. Keeps them from sticking in the salty environment that they are always in.
What salty environment are you in, the beach? Bleach flows on the inside of the hose. Do what works for you, but don’t give stupid advice here. This is a learning place where guys come for straight answers.
Anyway, I like the WD-40 silicone spray, keeps things nice and smooth. The collars on the SS female fittings need a little lube every now and then to snap on properly.
