Simpson 4240H downstreaming

I have a true dilemma. I recently bought a Simpson 4240H, 4200 psi, 4 gpm washer through Home Depot. The ad said it downstreamable. The injector tube connector is on the downstream end of it’s AAA Triplex pump. I read the Q & A material on the pump and several people said it that it was ok to use bleach with the washer. To be safe, I called Simpson’s cust. service dept. and asked. They said no, no bleach. Does anyone have an definitive answer?

That’s the unit I have. You can downstream bleach. Downstreaming is after the pump so it’s not hurting the machine.

The young lady I talked to at Simpson said she didn’t know and put me on hold to confer with someone else. I have a suspicion neither know doodoo about their products. Thanks Dogby92.

1 Like

No problem

Been there. It sort of worked, but the ratio sucked. The injector didn’t last long. I tried to rebuild it, but it never really worked again. I bought a whole new machine. If I were you, I’d cap/remove the injector and add an after market one from pressuretek.

Simpson is right in telling you not to use bleach. It won’t mess up the pump, but it will mess up the injector. They just failed to mention that you can put your own injector on there.

1 Like

I have the same machine you do I capped the existing injector and bought a nice one at the supply store. Because mine was was built on pump right after unloader don’t want to Risk it. It’s working great now

Besides that downstream sucks if you add more hose it won’t work . You need to be able to switch them out.

Thanks MikeyO. I’m going to do the same.

I added an adjustable downstream injector from General Pump. Works like a charm. Thanks for your help.

What size and gpm? Some say to go step down for better draw did you 3-5 or 2-3 gpm

3-5. Works great.

Do you have a part number or link for the injector you added? I am having the same issue… I am looking at a couple of them at Pittsburgh Spray Equipment.

Necro thread…

But you need the GP injectors, preferably the stainless version. For a 4/4 machine the 2-3gpm works well.