Engine does not continue to run

Hi John:
Sounds like it's too lean.
Try backing out the high speed screw 1/2 turn at a time until you don't need the choke. Then tune the high speed with saw running at full throttle. Screw in (lean) until RPM starts to drop, then back out 1/3 to 1/2 turn. Then set low speed at idle so engine is smooth but chain does not turn.

I have attached a diagnostic sheet to help you determine what is wrong.

Carb. needs to be rebuilt. If your choking the engine it to keep the alive and you've cleaned and replaced everything else, I would recommend carb. overhaul.

Sounds like the fuel pump is going out. Replace the filter first, as it's only $10. If that doesn't fix it, then it's probably the pump, which is $250.

Make sure your Air cleaner is not obstructed. Clean it!
Check your spark plug for the proper gap. Adjust your
LOW speed throttle screw. It may not be getting enough fuel flow. Check your fuel filter screen (Inside your gas tank). Good Luck

Check the fuel filter, air cleaner, and muffler for plugging. Check the fuel lines for decay or other damage. If this doesn't help, remove the carburetor, clean the interior with spray carburetor cleaner. Check the condition of the lower chamber diaphragm--it must be flexible with no cracks or holes. Hope this helps!

Here is a Link to a couple of my Tips that are the solutions to the symptom you describe:
www.fixya.com/support/r6081405-cleaning_small_engie_carburetor

If you need further help, let me know.

Good Luck!

Jm

Check the fuel filter, muffler, and air cleaner for plugging. Check the condition of the fuel lines for hardness, splitting, end rot, or kinking. Make sure the carburetor fasteners are tight. If no help, remove the lower carburetor chamber cover and examine the diaphragm and fuel metering valve that it controls. The diaphragm should not be hard, cracked or have any holes. The fuel valve has a rubber tip that may have deteriorated. If looks ok, then turn both L and H jet needles CW to stops (lightly), then back out CCW 1-1/2 turns each. Engine should start and run with these basic settings. Allow the engine to warm up, then pull the throttle full on. Adjust H needle CW until the engine speeds up somewhat, but is 4-stroking. Correct adjustment is when the engine continues to 4-stroke, but immediately 2-strokes when cutting. Allow to idle, and adjust L CW until the engine runs fairly well, but will allow the engine to 'follow the throttle'. Set idle speed screw so that the chain stops moving, but the engine continues to run. Hope this helps!

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