doug mccann
Recruit
- Joined
- Jan 24, 2003
- Messages
- 3
My 1986 35hp Merc runs great until you go past about 75% throttle. Then it flutters/stumbles and doesnt go any faster. It smoothes back out when you back off the throttle.<br /><br />I put new plugs in and it ran fine for one trip down the lake. Then back to same old problem. It has always been like this in the four years I have had it. Marina replaced fuel pump diaphram, checked carb, tried different prop, ran up the lake with voltage meter on it, checked compression, and cant find anything that causes it. I have also replaced bulb and hose to fuel tank. <br /><br />Because new plugs make a difference one time leads me to think it is something electrical. Coils maybe? Someone told me I should try swithcing to plugs with the j post instead of the flat/no post type called for. I'm wondering if the j post might hit the piston.<br /><br />Does anyone have any idea what is wrong with this motor?