Small Engines (Lawn Mowers, etc.)/carburetor setting

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Expert: John C. Bridgers Sr. - 9/27/2006


Question
Hi From Wales Uk.
I have a McCulloch Airstream IV Blower vac with a 21cc two stroke.

Do you know the screw settings for the carb High screw, low Screw and the choke flap stop screw as I have no idea and it won't start or run properly. Everthing has been cleaned and new plug etc..........but someone has messed with these screw settings?

Thanks Adrian  

Answer
 Hello Adrian:

 Turn Both H and L Screws Clockwise Until Seated. **DO NOT JAM SNUG ONLY** Now Turn Both Counter Clockwise 1 1/2 Turns. Holding the Throttle Full Open, Start the Engine. Adjust the H Screw In until the Engine Revs Properly. Then Allow Engine to Idle. Set the L Screw so there is No Hesitation when Going from Idle to Full Throttle. Now Set the Idle Screw. Hope this Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks.

 Good Luck

 Respectfully

 John

Small Engines (Lawn Mowers, etc.)

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John C. Bridgers Sr.

Expertise

Small Engine Service Center Co-Owner - ATVs, Mowers, Trimmers, Snow throwers, and Many Other Small Engine Operated Equipment. I can answer questions pertaining to Most Small Engines (Air and Water Cooled) and their Associated Equipment as well as Lawn and Garden Equipment, e.g. riders, tillers, trimmers, cement mixers, chainsaws, etc. I have been repairing small engines for 34 years. Briggs & Stratton, Tecumseh, Kohler, Lawn Boy, Stihl, Poulan, Mac, and Honda; to name a few.

Experience

I have been repairing small engines for 34 years. Briggs & Stratton, Tecumseh, Kohler, Lawn Boy, Stihl, Poulan, Mac, and Honda; to name a few.

Education/Credentials
Technical College for Gasoline and Diesel Engines. This was a Full Course on Complete Dis-assembly and Repair of ALL Components pertaining to Engines, Transmissions, Rear Ends, Electrical. I Found the Small Engines to be Interesting because they are Small and Simple.

Past/Present Clients
I have worked on small air/water cooled engines for 34 Years. I performed warranty work for Lowes of Wilson and other retailers in the area. I Own a Yard Maintenance and Certified Small Engine Repair Service Center.

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