Adjusting single screw carb on a weedwacker

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It's a 2 stroke craftsman, just did carb cleaning & has new diaphragm. Also, new spark plugs. Now it will not start on it's own. Sprayed starting fuel, it fires up. I think I messed up the single screw adjustment speed.
Is it 2 1/2 counterclockwise turn?
 
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Photo Please. There is sometimes another hidden adjustment under a plastic plug, especially if it is a slide style.

Also did you make sure the center stem of the diafram matched that old one. In some very rare cases if you place a short stem diafram in place long stem it will meter fuel only with lots of engine speed. However usually they wont idle.

Another thing that will go bad is the pump diaphram and it really isnt a pump, but rather two little flaps that must cleanly an easily seal against the aluminum body. It is possible that when the metering diafram drys out, its safe to assume the pumping diafram is not far behind.
 

Escape08

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I turned it in until it stopped and did 2 1/2 turns CC. It starts but dies right away. I will disassemble the carb once again & maybe I made a mistake somewhere. Thanks
20220720_182006.jpg
 
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Compression may be too low to properly modulate the diaphram to pull in the fuel.
 
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The screw on the left is the idle stop screw. Adjust it so the engine stays running but not at excessive rpm when the throttle trigger is released. You need to pull and release the trigger after each adjustment so the lever comes back to rest at its new position on the stop screw. There isn't a number of turns for these.

The screw on the right is the idle mixture screw. When there are two mixture screws the other one is high speed mixture, when there is only one it is always low speed. If it runs OK fast but not slow that often can be fixed by adjusting the idle mixture. Warm up the engine and keep it running by pulling the trigger as needed. Adjust the idle mixture so it runs better slow. There will be a place where the rpm is maximized at idle condition (trigger not pulled or only lightly pulled). Once you reach that point, adjust the idle stop screw for a decent idle speed. That is about where you want except you may need to turn the mixture screw out (counterclockwise, richer) a little if it seriously hesitates to rev up and/or stalls when you pull the trigger off of idle.

Looking at the picture again though I kind of wonder if you really have a single adjustment carb, or a two-screw one with the high speed screw gone.
 
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One other thing. Google "Home Garage" and "Inside House Garage" on youtube. Watch how he cleans the carburetor inlet screen after removing the needle and metering arm. I have had to resort to removing the screen like he does, and then blast some carb cleaner thru the port hole and also clean and agitate the screen to get it to flow.

Honestly I do give extra effort on the echo / stihl / husky / japanese rebadged units to save the carburetors, but often it is better to just get the cheapie one off the internet.
 

Escape08

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Yes, got it started !!! :D It took maybe 15 -20 minutes finding that sweet spot on the adjustment. Shouldn't have not touched the adjustment but my mistake was I didn't count the number of turns before I cleaned it. Lessons learned. Thanks to all the replies. It was surely educational for me.:D
 
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