Small Engines (Lawn Mowers, etc.): bolens BL100 Gas wead eater, internal passages, air mixture

Question
This has a 31cc engine and it won't throttle up but it idles fine. I have cleaned the carb mixed some fresh gas and checked the exhaust for blockage and didn't find any. This has been a gradual progession as it use to run fine for about ten minutes and then it would start to stall when trying to throttle up.  I have also checked the spark plug and it looks fine.

Answer
Hello James:

Did you Check the Spark Arrestor Screen in the Mufflerr for Blockage also? Have you Changed the In Tank Fuel Filter? Is the Trimmer Head Turning Smoothly? Is the Trimmer Head Gear Box Binding? Did you Soak the Carburetor Overnight in Cleaner? If No, then the Carburetor can Still have Varnish in the Internal Passages. Is the Carburetor Metering Pulse Jet Set Correctly? If Set too Low, the Engine will Perform as you Described. Are the Air Mixture Screws Set Correctly? The Following it the Instruction File for Setting the Air Mixture Screws.  Now Setting the Air Mixture Screws:  ****Turn the Idle Air and Main Air Mixture Screws In Until SNUG **Do Not Jam** Then Reverse Both Screws 1 1/2 Turns. Holding the Throttle Full Open, Start the Engine. Turn the Main Air Mixture Screw Clockwise Until Proper Revs are Obtained. Occasionally you May have to Turn this Counter Clockwise to Achieve the Proper Revs. Now Allow the Engine to Idle. Set the Engine Idle Screw (Not Idle Air) so the Engine will Stay Running if Required. Now Set the Idle Air Mixture Screw so there is No Hesitation when Throttling from Idle to Full Throttle. Reset the Engine Idle if Required.**** If you Hit a Snag or this Does Not Correct the Problem,  I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.

Good Luck

Respectfully

John

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Respectfully

John