2007 Yamaha 9.9 2 Stroke Won't Crank and Throttling Down

Joined
Apr 29, 2017
Messages
3
In the year I have had this motor, it has been very reliable. Prior to last week, it would always start after no more than a few pulls. Trip before last, the weather was a bit colder (45F) so I made sure the engine would crank before I left the house. It took me much longer than usual to crank but it finally fired. When I got to the ramp, again it took more cranks than usual to start. After running the motor with full throttle, I noticed the engine would drop to half throttle. I would back off then come back to full throttle where it would would run fine for 10-15 secs before it would throttle down again. On the way back to the ramp, I had no problems and this issue seemed to disappear.

This weekend the weather warmed quite a bit to 70F but I still wanted to test fire before leaving the house. It took quite an effort to finally get the motor to run; lots of pulling, full choke and a lot of throttle. After it started, it ran fine for 5 minutes so I decided to take it to the ramp. Once at the ramp, I could not do anything to get the motor to start. Pulled on it for a very long time with full choke, various levels of throttle and only had one pull result in the engine remotely trying to start. I'm pretty convinced there is nothing more I could have done to get it to start. When I got home, I pulled one of the spark plugs (the other was binded up and could not free it) and it seemed to be igniting fine and was covered in fuel.

At this point, I figure it is worth replacing the spark plugs but the issue may likely be with the carbs and that they need to be cleaned/replaced. Based on the symptoms and progression of issues, does anyone have any thoughts on what may be causing the problem and what the best course of action would be at this point?

Thanks in advance.
 
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