'02 Yamaha 40 Outboard

[Tic Tac 17]

I have a near mint 2003 Yamaha 40 hp short motor that was properly stored for a year. I recently dumped all the old gas, replaced the fuel line, cleaned the carbs and the motor seems to run fine out of the water with the water hose attached. As soon as I get in the water and attempt to give it throttle it cuts off like it has no torque. It just runs about 5 mph at full throttle and shakes, Please help? What is the next step? Thanks

 

[bgbass.1]

Re: '02 Yamaha 40 Outboard

it may be your high speed jet is pluged if you didnt remove them to clean probably still dirty

 

[birdbrain]

Re: '02 Yamaha 40 Outboard

will it run for a while, while it is in the down position or will it stall immediately? with the ear muffs, you are forcing water through your engine and therefore it does not overheat and shut off. Without the earmuffs the water pump is not generating sufficient suction to draw water all the way through the engine, it overheats and stalls. Possibly tilting the engine or driving the boat helps force water through the entire engine. Although not familar with your engine type Iv'e had a similar problem where water was even shooting out the little hole above water, but still not sufficient pressure to cycle water through the entire engine. Replacing the water pump fixed my problem. Although, my engine / boat had an alarm indicating over heat. Not sure if yours does have this alarm... Food for thought anyway.