1990 Mercury 9.9 STUMPED

[mgsolakis]

My Mercury 9.9 runs great at idle but won't go fast. Here is where I'm at: 1) Compression is good. 2) Spark is good. 3) I had a parts motor laying around and swapped out the power pack and coils. 4) cleaned the carb. The motor ticks along at idle and trolls like a champ but only goes half speed. PLEASE HELP

 

[MH Hawker]

What are the RPMs and pitch prop

 

[mgsolakis]

No RPM gauge and as far as the prop goes it's the same one that is on it when it ran good a few weeks ago on the same boat.

 

[enginepower]

pump the bulb and see if it goes any faster

 

[mgsolakis]

Pumping the ball does not seem to make a difference.

 

[mgsolakis]

To go back to what Hawker suggested, although I have no RPM gauge I don't think the motor is revving up to full RPMs.