I have a Honda HT3813. The engine is running very rough. I have changed the spark plugged but do not get full power. Engine also slows and stops at low throttle. How do I setup the carburetor ?
From memory, the only adjustment you can make is the idle, or tickover mixture - and that screw is under a 'tamperproof' cap. So, have a good look at the state of the air cleaner element - especially if its blowing a bit of black smoke.
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