I recently purchased this unit. It did sit for 3-4 years. I replaced impel thermostat quickly cleaned carbs. Unit starts right up and runs well in pail. Took it out and under load has little power, doesn't rev up under full throttle bogs down but doesn't stall. I disassembled carbs and cleaned them again, removing a lot of crap. Reassembled and took out again. Same issue and I'm not sure what to try next. Any help greatly appreciated