My 1980 Yamaha 20hp (20A 653 - 2 Stroke) originally had a problem with taking throttle when in gear and could only get around 20% and then would occasionally offer to go but never would, so i cleaned the carb and it made no difference. I then switched a carb from another identical engine (carb was fine on other engine), engine did start and run but not very well, it then proceeded to cut out and haven't gotten it going again yet, despite cleaning plugs and putting original carb back on, as it did start and run in neutral with the original carb. The plugs are sparking well and fuel is certainly present, compression is good (cylinder 1 - 125, cylinder 2 - 123). So i am baffled. My fuel is mixed correctly and is only a couple of weeks old, but will get fresh fuel 2moro and new plugs. Any help would be greatly appreciated! Cheers
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