25 hp yamaha 4 stroke carb ?? problem

[coastie88]

2011 25 hp yamaha 4 stroke approx. 10 hrs on engine. Starts and idles great. Runs bad or cuts out when open throttle. Mechanic cleaned carb three times, good compression, replaced plugs,fuel filter,fuel tank,fuel line,checked timing,and replaced stator. He is out of ideas and unable to get in contact with Yamaha techs. Anyone have any ideas.

[Jason2tpa]

2011 25 hp yamaha 4 stroke approx. 10 hrs on engine. Starts and idles great. Runs bad or cuts out when open throttle. Mechanic cleaned carb three times, good compression, replaced plugs,fuel filter,fuel tank,fuel line,checked timing,and replaced stator. He is out of ideas and unable to get in contact with Yamaha techs. Anyone have any ideas.

Reply back with the complete model number. Let me make sure this is clear...this engine is 6 yrs old with only 10 hours? Never heard of that, but ok. If this is true then obviously the engine sits for very long periods of time. Is fuel drained when you're not using? If not then fuel sitting that long will definitely muck up everything its in contact with. Despite an engine used for only 10 hrs total should not need carbs cleaned, what does this mechanic do to clean the carbs? if fuel is not drained, sitting that long the jets will get clogged. They need to be pulled and thoroughly cleaned so you can see through the orifice. Each jet.

[woodenlure]

If someone remove the plug, on the pilot jet, and adjusted the jet way too far, this will happen. I have an f20 and it happened to me as I was having a cold start issue with the "Prime Start".

[coastie88]

25hp yamaha 4 stroke

I bought boat and motor from friend. He towed boat behind his house boat. He only used house boat once a summer.Out boars is F25SEHA. When I first tried to use it started and idled fine but would cut out each time I opened throttle .After I made it back to dock( after about 10 restarts.,I tried again and was able to make about 5 full power runs.I did not want to go out for obvious reasons . I decided to take to mechanic after reading about carb problems on this engine.It has been downhill ever since.

[coastie88]

25hp yamaha 4 stroke

I bought boat and motor from friend. He towed boat behind his house boat. He only used house boat once a summer.Out boars is F25SEHA. When I first tried to use it started and idled fine but would cut out each time I opened throttle .After I made it back to dock( after about 10 restarts.,I tried again and was able to make about 5 full power runs.I did not want to go out for obvious reasons . I decided to take to mechanic after reading about carb problems on this engine.It has been downhill ever since.

[rodbolt17]

find a real tech.
two reasons it may cut out.
lack of fuel or lack of spark.
both are easy to test.