Mariner 30E 80’s model 2 stroke

[AV803]

Motor is sputtering at wide open throttle. Almost seems as if it’s hitting a rev limit and it won’t pick up any more speed or plane out.

I’ve changed the fuel pump, cleaned the carb, replaced fuel lines, and filter.

I’m not sure what direction to go in. From information I have found it could be a timing advance or spark issue?

I have a clip below for reference! I’m desperate.

 

[AV803]

I posted this on Yamaha forum because it is the Japanese Mariner when Yamaha made them!

 

[guyjg]

Run it on a different tank to see if it changes.