1997 Tohatsu 9.9

[bwood1207]

I have a 1997 9.9 2 stroke Tohatsu on my 1448 Jon and I am having some trouble with my engine. I have put the throttle cam and boysen reeds and everything was running great. Now last night I noticed it is really slouchy getting out of the hole and I have even noticed it was constanly changing rpms at WOT runnning down the lake, like it has a somewhat of a surge to it. Was wondering what some of you guys thought whether it is the carb or what. Like I said it is stumbling alot out of hole then finally picks up, then running down the lake it surges RPMs up and down very little.

 

[pvanv]

Re: 1997 Tohatsu 9.9

I assume you have already checked the basics -- the carb to be certain it's crud-free, and also fuel pump delivery, and coil impedances.

Verify timing, in case the 15 hp cam slipped, or was installed a little off. Also check for a cracked reed. The Boyesen reeds will cause more fuel spitting at low RPM, but if not cracked (they are more fragile than factory reeds), they should work OK at WOT, and give good hole shot.