Small Engines (Lawn Mowers, etc.): carburetor setting, blower vac, wales uk

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