'94 Yam 250 surging issue

[accolyte1022]

My '94 250 Yam. will rev up to ~3000 rpm for several seconds and the drop to ~2000 rpm. It will then "try" to go higher maybe 2,300. Rebuilt carbs, tps was 4-6 k. Ohms as per manual on one extreme but 140-195 on the other (manual states 4-6 on that end as well. Replaced TPS, checked out fuel pumps, top pump had air leak, went ahead and replaced all three. Took the boat out again and the EXACT same thing happened! I'm getting frustrated at this point, ordered a tech manual hopefully this will help me more than the Clymers man. Does anyone have any other ideas (would love to go out this weekend!)


Thanks in advance,
Brian

 

[grid]

Re: '94 Yam 250 surging issue

Pull the carbs again. Yeah, I know...I think when you flip the carbs upside down to remove the bowls, something in one of the bowls is sliding to a hiding place in the body, then dropping back down to block a main jet-or 2-when you reassemble.