Simpson CM61083-S Pressure Washer Fuel System

New guy here.  I'm 71 and have a ton of experience with small engines.  A couple of years ago I bought a Simpson CM61083-S pressure washer, I believe on Amazon.  The reviews were very good, and the price/performance were very attractive relative to other offerings.  I have seen a post online that the engine, Simpson model CRX208cc, is copied from a Honda engine, and it does look for all the world like a Honda engine.  The first time I used it, I was totally amazed.  After I finished, as I always do, I turned off the fuel valve, let it run until the carb was empty, and siphoned the remaining gas from the tank.  The next time I used it was about 6 months later.  Filled it with fresh gas, turned on the fuel valve and pulled the cord about 50 times.  Nada.  Pulled the plug and checked for spark.  Next I filled a syringe with gas and squirted about 5 CC in the intake.  Sputtered for a few seconds.  Did it again, and after it started, just kept squirting gas until it would run on its own.  The engine was loping (rpm running up and down) a lot, like you would expect with stale gas. Not the case. I washed the garden tractor with it running like that for 10 minutes or so.  It maybe got a trifle better, but was never really happy and won't idle.   I'm thinking adjust the carb for probably a different blend of gas/ethanol, but can't find any adjustments.  
 
So, I decided to pull the carb and clean it just for kicks, knowing it wouldn't fix anything.  It was spotless and beautiful inside.  Looked like new.  Reinstalled it and it still runs the same.  I worked on a Craftsman pressure washer a while back for my brother-in-law that had the same symptoms.  It, too,  had the "not" adjustable carb.  I bought a new carb online for his and after installing it, it ran fine.  
 
It has been sitting around for over a year, and today I decided to try to do something with it again.  I see what I think is a correct carb on ebay, but this doesn't make any sense to me.  I don't understand what happened to a brand new carb after being used just one time, drained and properly taken care of.
 
Can anyone hold forth on this problem?  It doesn't make sense to chuck a brand new carb that should be working fine.  
 
I can't get the site to let me upload pictures, but, trust me, the carb looks pristine inside.
 
Best
 
Mike

Hi, Scott:
 
Well,  you were spot on.  Apparently you have seen this critter.  I didn't realize what that was.  That gives me a red face in 2 ways.  Back when I ran it the second time (when it was surging) as usual, I turned off the fuel and let it run until it quit.  I left the gas in, thinking I'd get back to it, and it has sat for nearly a  year.  I'm guessing that fuel shut off must let a little gas trickle through, as there was a little gunk in the carb this time.  Pulled both jets and gave it a good soak in lacquer thinner.  Sprayed carb cleaner through all the passages, cleaned the main jet thoroughly in carb cleaner, making sure all the little holes were clear, and cleaned that little mystery one you mentioned the same way.  Blew 70 PSI compressed air through every passage I could find, and the jets.  Have it back together now, but didn't arrive at happy land. 
 
Filled it with fresh gas, set the choke and it hit on the first pull.  Ran for a second and died.  Wouldn't hit again, choke or not no matter how much I pulled on it.  Pulled the drain plug from the carb and it is getting plenty of gas through the float valve.  Put that back and pulled it again.  Ran for a second.  Waited 5 minutes and it ran for a second.  After about a half hour of this routine, I found out that if I start it at about 1/2 throttle, it will run, but surges, sputters and misses out a lot.  Try to give it a little more throttle, no matter how gradually, and it dies instantly, like you turned it off.  Feels like the original problem, only worse.  This is what I expect when working on a carb with ADJUSTMENTS.....and set too lean.  Unfortunately, no adjustments.  
 
Starting to feel the price of a new carb slipping away.  I can afford it, but I can't buy one every time I want to use it.  Hate to impose further on your kindness, but do you have any more suggestions?  You seem to be familiar with this beast.
 
Best
 
Mike
 
 

Looking at a pic on-line a couple things.  Seems you have a fuel filter as part of the on/off fuel valve.
Remove that cup.  There's usually a screen inside there.  Make sure that clean and again fuel flows thru it when turned on..
 
Second, just for S & Gs, that machine has a low oil cut off switch.  It's not un-common for it to fail.
On the front of the engine is a sensor with one wire that plugs into the harness.  Simply un-plug it to 
disable it...  It's supposed to kill spark but when failing it often PARTIALLY KILLS SPARK.  It can have you chasing your tail....
 
..

Hi, Scott:
Went through that carb again.  I grabbed my bundle of old guitar strings and selected the best fits for each hole.  Roughed up the guitar strings with coarse sandpaper and worked the best fit through every orifice I could find, including all of those in that "emulsion tube".  I may have wallered out that one you told me about ever so slightly.  Blew everything out again with compressed air and put it back together.  As I suspected, absolutely no difference.  Ran it for 10 minutes again.  This is immensely frustrating.  What the heck can be wrong with that dang carb that I can't find????  Is there some passage somewhere I'm not finding??  
 
Misc observations:  Choke on, choke off, runs the same.  I can mostly block the intake with my fingers and it makes no difference.  On the side of the tank it states that the engine was tested with gasoline containing "ethanol shield" whatever that is.  I don't have any.  I have Stabil regular and marine formula, but can't imagine it would matter for this problem.  
 
While I'm waiting for any wisdom, I'm going to start searching the internet for a new carb.  I won't order one until I hear from you.  If I find one, I know it will fix the thing, because I've been down this road several times and it always does.
 
Again, thanks for your time.  Probably have too much angst, agony and labor in this to keep working on it.
 
Best
 
Mike

Well, it didn't post the links.  Is that illegal?  I'll try again:
 
Simpson:  
 
Honda:  

You pulled the long, thin emulsion tube (that's under the main jet) correct?
 
I'm not a fan of the aftermarket Chinese knock off carbs but yours IS a
Chonda (Chinese knock off Honda engine).  
 
I looked but couldn't find the carb listing as you posted.. 
I'm sure it would be fine.  
 
The all in one kit for $22 is likely not a genuine Simpson part.  You get what you pay for and all those parts are likely not going to last...  If you can find a genuine Simpson carb (if what your looking at isn't), I would look for that...
 
Re the Honda carb... That very likely would fit and not give you any issues-It's just going to be manufactured better and last longer...
 
Good luck and please post back how it goes..
 
.

Hi, Scott Et al:
 
Well, I am dumbfounded.  I got the new carb in there today.  Had to pull the throttle shaft out and drill a small hole in the plastic travel limiter on top of the throttle shaft for the little throttle return spring, which the new carb didn't come with.  Installed the spring on the new one and it works the same as it did on the old one.   Other than that, it all fit perfectly.
 
Started on the first pull at half throttle, and runs almost exactly as terrible as the old one.  The one screw adjustment it has that the other didn't, (Idle mix, I suspect) doesn't do much, but I didn't fool with it very long as I didn't have water hooked up, and it isn't going to fix the problem anyhow.  It will almost idle normally.  I can advance the throttle to about 1/2, where it sputters and surges constantly.  Advance the throttle a bit more and it is like you turned off the switch.  Drops dead on the spot.  
 
The kit came with that little module that connects to the low oil shutdown, so I put that on there.  No help.  Unhooked the on/off switch completely.  No help.   On a lark I put the new spark plug in there.  Again, no help.
 
Could I be looking at a bad ignition coil?
 
Other than that,  I'm out of ideas.  I'd have bet 100 bucks that carb would fix it.  
 
Hope one of you guys has an inspiration...
 
Mike
 
 
 
 

Hummm...  As it seems you ruled out the carb (been thru everything) time to look at ignition.
 
Did you pull the spark plug, ground to the head and check for spark?
 
Just for S & G's, You might pull the flywheel and make sure the key isn't sheared or partially sheared.
That could allow to run crappy.  
 
.
 
.

I just finished repairing a customers Ryobi2200 "suitcase" generator. 
 
Checked (pulled the carb) the carb, nice and clean...
 
It would fire off on the first pull, then nothing.  Looking at it and the limited parts
list, I was looking for a low oil cut off switch.  I never found it on the machine or parts list.
 
That switch (you likely know) when working correctly (low oil level) will kill spark
after the first revolution or two.  Changed the nasty oil and then put an in-line spark tester
 
Sure enough, started, sparked a touch and then no spark (VERY obvious)... An electrical issue.
 
Lots of wires obviously.  Un-plugged a 2 wire connected right out in the open.
Cranked it up, ran /runs like a top!   I tried to follow the wires, they went into the main
generator electrical box...  Everything works, (auto throttle).   
 
I suspect a low oil switch, but,, it runs with no mods, just on plug un-plugged..
 
.
 
 

Also, I'd dump ANY SUSPECT fuel and put known good fuel in there.
 
No additives at this point.