# Confused about my chemical injector, or maybe DSing in general



## 804 Paint

OK, I had already purchased the Simpson ALH4033 before Ken had a chance to chime in. It's my first machine I don't really want to spend the extra coin until I have more business anyway.

SO, the specs on it say it has a downstream injector, and by all accounts, it looks like it has one. The fitting for the siphon hose is just before the hose QCC. OK. So, why does the manual say, "*Do not use bleach"*? When referring to rinsing the injector after the use of chemicals, it also says, "If chemicals remain in the pump, it could be damaged."

If it has a downstream injector, _then how would chemicals even enter the pump??_ That's the most confusing thing to me.

Last thing, if indeed this is an onboard downstream injector, how does this differ from aftermarket injector kits such as the ones sold by Pressure Tek?

Edit: Sorry, another LAST thing…the manual says it pulls chems at a 7:1 ratio, but later in the specs it says the "soap consumption rate" is 10% max. What is the "soap consumption rate?"

Let's say it does what it said earlier in the manual and pulls at 7:1. So, anything siphoned at 100% concentration will by diluted down to about 14%, correct? So if regular household bleach is knocked down to 8% already, then I would only be applying about a 1% solution, correct? Even bumping up to pool bleach at approx 12.5% only brings it up to about 1.7% at the 7:1 ratio. So, bottom line, what is the % of sodium hypochlorite we want coming out of the end of the wand for general house washing?


----------



## stelzerpaintinginc.

Can you post a pic of the part of the washer that shows the injector, relative to the pump?


Stelzer Painting Inc.


----------



## 804 Paint

Sent from my iPhone using PaintTalk.com


----------



## Dave Mac

I am pretty sure you can still use a aftermarket down streamer and avoid using that built in one on the machine.


----------



## 804 Paint

Dave Mac said:


> I am pretty sure you can still use a aftermarket down streamer and avoid using that built in one on the machine.


Thanks but that really doesn't answer the question. If what I have is a DS injector (and looks like it is), why use an aftermarket one? And if it is a DS, why would not rinsing with water after use (which I would never do) damage the _pump?_


----------



## Jmayspaint

I don't see how it could unless there is some situation where there is back flow into the pump. Using bleach through it may void your warranty so that would be the reason to use aftermarket. Personally, I wouldn't worry about it. We have used on board injectors for bleach on multiple machines for years and haven't had a problem. They all say 'don't use bleach' I think it's just a$$ covering on the part of the manufacturer. 

I do always rinse with water after use. IME the onboard injectors are much more reliable than after market ones. 

I would also like to hear Ken's opinion on if there is ever a situation where back flow could occur.


----------



## 804 Paint

Jmayspaint said:


> I don't see how it could unless there is some situation where there is back flow into the pump. Using bleach through it may void your warranty so that would be the reason to use aftermarket. Personally, I wouldn't worry about it. We have used on board injectors for bleach on multiple machines for years and haven't had a problem. They all say 'don't use bleach' I think it's just a$$ covering on the part of the manufacturer.
> 
> I do always rinse with water after use. IME the onboard injectors are much more reliable than after market ones.
> 
> I would also like to hear Ken's opinion on if there is ever a situation where back flow could occur.


Definitely. I also don't see how using the onboard vs the aftermarket would really be any different as far as a backflow issue would be concerned. They are both just before the hose is connected, so…


Haven't used the unit yet but I definitely don't want to void the warranty.


----------



## Dave Mac

cant you suck some soap through it and see if it is going through the pump or not?? if it is going through the pump which I was thinking it would, then I would suggest using a after market downstream. I always thought built in injectors were upstream injectors. So that is a little confusing


----------



## 804 Paint

Dave Mac said:


> cant you suck some soap through it and see if it is going through the pump or not?? if it is going through the pump which I was thinking it would, then I would suggest using a after market downstream. I always thought built in injectors were upstream injectors. So that is a little confusing



How would I be able to tell if it's going through the pump or not?


Sent from my iPhone using PaintTalk.com


----------



## Jmayspaint

804 Paint said:


> Definitely. I also don't see how using the onboard vs the aftermarket would really be any different as far as a backflow issue would be concerned. They are both just before the hose is connected, so…



Not necessarily. The after market ones can be used at any position. The one I have is on a two foot piece of pressure hose so it's a little farther away from the pump even if its installed directly to the pump. They can also be used in the middle of your lines so if you are running two 50' lines it could go in between them. 

My sand injector draws at the end of the wand right before the tip. No sand ever goes through the lines, but the injector effect still works.


----------



## Jmayspaint

Dave Mac said:


> I always thought built in injectors were upstream injectors. So that is a little confusing









Some of them are but not all. The ones I've seen that are, are usually on smaller home owner models. Both of my current washers have onboard downstream similar to the one in the OP.


----------



## Hines Painting

I bought a simpson 11 months ago and the injection stopped working on the second job. I havent been able to get the onboard or an aftermarket to work since. 

So, yesterday I pulled the trigger on a pressure-pro belt driven unit.

Hopefully you have better luck with simpson than I have.


----------



## PressurePros

If that is where you connect your pressure hose (at that coupler) it is a downstream injector. Now here is the bad news. Unless I am looking at that wrong, the injector looks like it is built into the unloader/pump. That means you can never bypass it, nor can you easily replace it. That would be equivalent to an oil filter being welded onto an engine block. You will have to figure out how to rebuild that injector. That makes no sense to me so hopefully I am looking at the picture wrong. 

There isn't really concern for backflow into the pump so I am not sure what the literature is talking about bleach being in the pump. I've never used a machine with this type of setup so I am taking an educated guess for my reply. Sorry I couldn't be more help.


----------



## PressurePros

I would figure out a way to remove that injector (unscrew it and plug the hole) then use an aftermarket injector. Its not that there will be a flow benefit in terms of how much chemical is pulled (usually about 12:1 dilution), but when that injector fails you will be in the middle of a job and the fix is best done before hand at your shop.


----------



## Hines Painting

I put a plug in mine and still couldn't get an aftermarket to work.


----------



## Damon T

I had a pressure washer that had a built-in downstream unit. After that one failed I could not get an aftermarket one to work no matter how many times I tried. I am very happy with the unit I have now that uses replaceable downstream units


Sent from my blah blah blah


----------



## stelzerpaintinginc.

Damon T said:


> I had a pressure washer that had a built-in downstream unit. After that one failed I could not get an aftermarket one to work no matter how many times I tried. I am very happy with the unit I have now that uses replaceable downstream units
> 
> 
> Sent from my blah blah blah



And what unit is that? I'm shopping around for a better one, which is why I ask. 


Stelzer Painting Inc.


----------



## Damon T

stelzerpaintinginc. said:


> And what unit is that? I'm shopping around for a better one, which is why I ask.
> 
> 
> Stelzer Painting Inc.[/
> [http://store.spraymallstore.com/e4...e link works.
> Sent from my blah blah blah


----------



## 804 Paint

PressurePros said:


> I would figure out a way to remove that injector (unscrew it and plug the hole) then use an aftermarket injector. Its not that there will be a flow benefit in terms of how much chemical is pulled (usually about 12:1 dilution), but when that injector fails you will be in the middle of a job and the fix is best done before hand at your shop.


How would one go about this? And the injector, is that the entire brass part? Not sure how one would go about that. If you are taking about just where the siphon goes, it's that small fitting just before the QCC for the hose. No way to unscrew that thing. I'll post more pics from various angles in a bit.

The thing is, I picked up this washer for about $825. The 4.0 GPM, belt-driven models with separate unloader (which I don't know how to identify) seem to start around $1500…almost twice as much. I don't think I can bite that bullet quite yet.


----------



## 804 Paint

OK, I see those 5 alan screws there, but after I took that piece off, how would I connect water, connect a hose, etc?
















Sent from my iPhone using PaintTalk.com


----------



## 804 Paint

Hines Painting said:


> I bought a simpson 11 months ago and the injection stopped working on the second job. I havent been able to get the onboard or an aftermarket to work since.
> 
> So, yesterday I pulled the trigger on a pressure-pro belt driven unit.
> 
> Hopefully you have better luck with simpson than I have.


I know, I read all about your woes! Not real smart, am I? :jester:


----------



## squid

804 Paint said:


> OK, I see those 5 alan screws there, but after I took that piece off, how would I connect water, connect a hose, etc?
> 
> View attachment 25665
> View attachment 25666
> 
> 
> 
> Sent from my iPhone using PaintTalk.com


 Whoa!

There's no reason to remove anything. Behind the injector nipple is a ball and spring that opens when it senses the flow rate produced by the 0 tip. They are stainless steel and should hold up to bleach depending on what part of China they came from. Occasionally, the ball may stick but can be freed up by sticking a stiff blunt object into the injector. Wash out the injector after use and squirt a little wd in there.

Forget about the math. Go find a moldy north side of a relatives house and trial/error till you get a good ratio.


----------



## Dave Mac

Squid the reason Ken was suggesting that he uses a injector that cam be removed is because the injectors are the first thing that brakes down, so you do not want to be with out a back up plan in case of failure in the field. Its very common to go through a couple injectors in a week sometimes.


----------



## squid

Gotcha Dave. You would now.


----------



## 804 Paint

squid said:


> Whoa!
> 
> There's no reason to remove anything. Behind the injector nipple is a ball and spring that opens when it senses the flow rate produced by the 0 tip. They are stainless steel and should hold up to bleach depending on what part of China they came from. Occasionally, the ball may stick but can be freed up by sticking a stiff blunt object into the injector. Wash out the injector after use and squirt a little wd in there



Thanks. Now, what do I do when the injector fails? I think the point being made is that it is impossible to use an aftermarket injector with an onboard injector still attached. 


Sent from my iPhone using PaintTalk.com


----------



## PressurePros

804 Paint said:


> OK, I see those 5 alan screws there, but after I took that piece off, how would I connect water, connect a hose, etc?
> 
> View attachment 25665
> View attachment 25666
> 
> 
> 
> Sent from my iPhone using PaintTalk.com


The only thing you would unscrew and replace with a plug would be that screw-in barb where the downstream hose attaches. Unscrew it and look inside (or take a picture with a flashlight so we can see what going on in there)


----------



## PressurePros

This is the piece. With a plug, it should just bypass. 

But... from the other guys that tried this, there still may be a flow restriction which would cause issues with aftermarket downstreamers. If that is the case, you may have to drill out the inside of the downstreamer and that would void your warranty.


----------



## 804 Paint

K, so what is the black handle/knob thing at the top? I unscrewed the knob earlier and there is a large spring under it. I could not see how compressing the spring by tightening the knob would affect anything. 

I'll get pics of the other piece a bit later. Where would I find a brass plug for it?

Really appreciate the help. 


Sent from my iPhone using PaintTalk.com


----------



## Hines Painting

It should be threaded for 3/8 npt. You can get a plug at any hardware store.


----------



## 804 Paint

Sent from my iPhone using PaintTalk.com


----------



## PressurePros

Yikes. That black thing you unscrewed exposing the spring is/was your unloader. It was probably factory set. Put it back on and you are going to have to reset it. Do you have a pressure gauge?


----------



## Hines Painting

Simpson claims the unloader is adjustable to lower the pressure if needed...ive spun mine all over trying to get the injector working and it didn't seem to cause any problems when I've used it since then. If you twist it down you can actually feel the pressure decrease.


----------



## PressurePros

Hines Painting said:


> Simpson claims the unloader is adjustable to lower the pressure if needed...ive spun mine all over trying to get the injector working and it didn't seem to cause any problems when I've used it since then. If you twist it down you can actually feel the pressure decrease.


Don't use an unloader to lower pressure. You lose flow that way and turn it into a homeowner unit (2 gpm or less). Its best to use set the unloader once and leave it alone. Adjust your pressure using the right nozzle orifice.


----------



## 804 Paint

PressurePros said:


> Yikes. That black thing you unscrewed exposing the spring is/was your unloader. It was probably factory set. Put it back on and you are going to have to reset it. Do you have a pressure gauge?



Weird I cannot see what it affects...ie how losening/tightening it puts pressure on anything. It wasn't on tight at all so if it wasn't meant to be touched they sure didn't do a good job because just bumping it would have moved it. 

So what do you think of the injector since the pics? Any reason it cannot be bypassed?

Guess I'll be ordering a pressure gauge from PT along with the outboard injector!


Sent from my iPhone using PaintTalk.com


----------



## PressurePros

804 Paint said:


> Weird I cannot see what it affects...ie how losening/tightening it puts pressure on anything. It wasn't on tight at all so if it wasn't meant to be touched they sure didn't do a good job because just bumping it would have moved it.
> 
> So what do you think of the injector since the pics? Any reason it cannot be bypassed?
> 
> Guess I'll be ordering a pressure gauge from PT along with the outboard injector!
> 
> 
> Sent from my iPhone using PaintTalk.com


They can feel loose but are adjusted to prevent too much pressure building up inside the pump. Without it, catastrophic failure. 

It's gonna be trial and error with getting an aftermarket injector to work. I suggest you get a 2-3 gpm injector (even though your machine is rated higher) if a 3-5 gpm injector doesn't work. The 2-3 gpm injector should work if the flow is still restricted by the stock parts.


----------



## 804 Paint

PressurePros said:


> They can feel loose but are adjusted to prevent too much pressure building up inside the pump. Without it, catastrophic failure.
> 
> It's gonna be trial and error with getting an aftermarket injector to work. I suggest you get a 2-3 gpm injector (even though your machine is rated higher) if a 3-5 gpm injector doesn't work. The 2-3 gpm injector should work if the flow is still restricted by the stock parts.


Should I tighten or loosen to decrease pressure? I ordered the gauge just want to be on the safe side when firing it up. 





Sent from my iPhone using PaintTalk.com


----------



## PressurePros

Tightening lowers the pressure that will make the pump go into bypass. With your gun on and pressure gauge inline, tighten down until you read a couple hundred psi below your rated pressure.

Eg:
If your machine is rated for 4000 psi, you can twist it down til pressure gauge reads 3800 psi. It is better to start with it twisted down a bit then back it off until you get your desired psi. Don't set it below your rated psi unless you plan on using larger orifice nozzles to run lower pressure at the gun. While you are ordering your parts from PT, order a JRod and nozzles. Call Bob and he will tell you what nozzles you will need for downstreaming.


----------



## Hines Painting

PressurePros said:


> Tightening lowers the pressure that will make the pump go into bypass. With your gun on and pressure gauge inline, tighten down until you read a couple hundred psi below your rated pressure.
> 
> Eg:
> If your machine is rated for 4000 psi, you can twist it down til pressure gauge reads 3800 psi. It is better to start with it twisted down a bit then back it off until you get your desired psi. Don't set it below your rated psi unless you plan on using larger orifice nozzles to run lower pressure at the gun. While you are ordering your parts from PT, order a JRod and nozzles. Call Bob and he will tell you what nozzles you will need for downstreaming.



Could that being tightened wrong mess up the injector?


----------



## PressurePros

Hines Painting said:


> Could that being tightened wrong mess up the injector?


Maybe? I'm thinking if you have too much bypass, your flow is lower than what you think it is. If you have a 3-5 gpm downstreamer and are bypassing so much that your flow is well below 3 gpm, that theoretically could affect the venturi effect that makes a downstreamer work.


----------



## Palnews26

New Motorcycle or New Power Washer.
The results will be the same.

http://www.youtube.com/watch?v=Q9zNUPDmnz4


----------



## 804 Paint

PressurePros said:


> Tightening lowers the pressure that will make the pump go into bypass. With your gun on and pressure gauge inline, tighten down until you read a couple hundred psi below your rated pressure.




WHOA! This is incorrect. Want to post it here in case anyone else comes across this post. I had yet to fire up the machine at all until today. To be on the safe side, I tightened it down pretty far to make sure I was well below 4000 PSI on initial startup. After I got it started, the 5000 PSI gauge maxed out instantly. In a panic I tighten it down more and more but nothing improved so I cut the machine off. I loosened it all the way and started over and it was well below operating PSI.



I don't know if I screwed anything up or not, but my engine doesn't sound great. It's real up and down when the gun is in bypass. I took a video but I'm not sure if we can upload videos aside from first uploading to YouTube or something.

Edit: I would describe the engine sound as "pulsating" when the trigger is not depressed. I don't think this is normal.


----------



## Hines Painting

Did you put the oil in it?

Did you shut the choke off?

How old was your gas?

Is your line or gun leaking?

Is your idle up all the way?

Is your water pressure from the hose good?


----------



## 804 Paint

Hines Painting said:


> Did you put the oil in it?
> Yes
> Did you shut the choke off?
> Yes
> How old was your gas?
> 5 minutes
> Is your line or gun leaking?
> No
> Is your idle up all the way?
> Yes
> Is your water pressure from the hose good?
> Yes


"The message you have entered is too short. Please lengthen your message to at least 4 characters."


----------

