Stihl flooding after adjustment

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Waterboy86

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Hi all. Im new here. Just bought a used stihl ms290. Started it before i bought it and it started right up. Started it the next day and it fired right up. Once it was running i played with the carb adjustments until I got it running to what i thought was good. Shut it off and went to restart it cold later that night. Now it floods and wont start. I pull the plug and its totally saturated. Blow out the cylinder and clean the plug and it immediately fouls again. Obviously i screwed something up but i have no idea how to even baseline it to where i can get it to run since the carb has the limiters removed. Please any help would be greatly appreciated. I know there are some real guru's here.
 
Welcome to AS. Take the carb back to the default settings of 1 & 1, adjust the idle speed and see how it goes. I'm assuming that you have no limiters on the adjustment screws?
 
Thanks for the welcome. Im assuming that i have no limiting screws. There's an awful lot of adjustment available. Something like 5-6 full turns. You're saying that i should screw the adjustment screws all the way in(clockwise) then back out 1 full turn each? What about the idle screw? And just for clarification, its fouling to the point that the plug is totally wet with the choke off.
 
...if you feed too much fuel the engine will drown and die. That's what the initial setting (L and H 1 turn out) is for: to enable the engine to start and run. Once the engine runs the carb can be fine-tuned.
L and H regulate the fuel supply (through the jets in the carb bore; L = idling and acceleration, H = high speed) while T (also TA or LA) regulates the air supply at idle (via the throttle valve angle).

The final setting should not deviate too much from the initial setting. If it does there is something wrong with the engine/carburetor.
 
Got the saw started today. Thanks everyone for the help. Guy i work with that used to work for a tree service and got it started by playing with the throttle while cranking. Any further advice on what it would take to make the saw start easier? I followed the advice i had read about setting the idle and tuning the high screw at full throttle until it bogs a bit then going slightly leaner from there. Obviously im doing something not quite right though.
 
Haha yeah that was a tough pill to swallow. As someone that pays his mortgage fixing engines this was very humbling. I took a saw that started right up and got it to the point that i can only start it with the air filter off. Life lessons for sure.
 
.... and tuning the high screw at full throttle until it bogs a bit then going slightly leaner from there.

That may be rich. As mentioned above, it should be close to the 1 turn. You want it to gurgle (four stroke) at wot (wide open throttle) when not cutting and then run clean under load when it is cutting wood. Many good vids on youtube.
 

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