by bgsengine » Sun May 29, 2022 6:30 pm
OK sounds like it may be running rich under load... simple things to check: how dirty is the carburetor on the outside? (Thinking the bowl vents and air bleeds) - Does it seep any fuel at all anywhere? (float needle not seating properly) - Carburetor may need cleaning (Blocked air bleeds, etc) - might also consider checking flywheel key (unlikely , but a slightly sheared key can bump ignition timing enough that it'd go rich under loads) does it have one of those "extra quiet" spark arrestor mufflers? (possible blocked spark arrestor screen) ... Try a new spark plug (especially if yours is a champion - they are prone to fouling and misfiring, in my experience - NOTE: NEW does NOT mean GOOD! ) do a leakdown test and look for possible valve leak (and/or sticking valves is another possibility, leakdown may not show that though..) thats a few things I can think of you might wanna check on... (when the bogging down happens, look close at exhaust if it looks like dark blue-black smoke, it is running rich for sure.. so, carb or a misfire, or timing's off)
Edit: on the other hand, when the problem does happen, try and squirt a shot of extra fuel (or carb cleaner) into the carb throat (air cleaner off) , if it improves, then it may be too LEAN, under load (or an air leak after the carb - gaskets, etc)
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)