I have a handed down Yardman Lawn Tractor with a 19.5HP Briggs & Stratton 3672CN engine. Got this last year and ran fine all year without problems starting or running. Haven't run it in several months and when I tried it last week the battery was too low to turn engine over. Replaced battery but then engine would just crank and crank and never fire. Pulled air cleaner off and sprayed some starter fluid in and would run until fluid ran out and then cut off. Pulled carb and cleaned everything I could with carb cleaner and made sure everything was free moving. Pulled cap lock screws out and float was trapped under mid-gasket and didn't have a new gasket so I sprayed in the float area with carb cleaner without removing it. Pulled the plug on the side of the float area and let the carb cleaner run completely thru. Replaced fuel filter even though fuel was free flowing. Replaced carb and after starting with starter fluid a few time, it started running on it's own. Idled fast and stayed running smooth as long as I just let it sit there.
I put it in gear and moved forward and backwards a few times and as soon as any additional load was put on the engine, the engine would slow, the lower butterfly below the carb would start to shut and the engine would just cut off. Also, if I even just barely started to engage the blades the engine would die. Was told there was also an oil level safety on this engine but the oil level is correct. It appears that the engine runs fine but has no power under load. When any load is added to the idle condition the engine dies. I tried adjusting the metering needle screw on the carb but that had no effect unless I went in too far and then the engine would sputter and die.
Any and all help would be greatly appreciated as with the recent rains I will soon need a field guide to find my front door :O)
Scott snipped-for-privacy@gmail.com