increasing fuel efficiency when rebuilding a powerhead - The Hull Truth

willxfs · 09-26-2008, 10:02 AM

I have an old 1993 carbed yamaha 200. When the time comes I will probably have the powerhead rebuilt. Are there any modifications that can be done during the rebuild to increase the motors fuel efficiency. Thanks -will

A1 Outboard · 09-26-2008, 12:38 PM

With a rebuilt powerhead, after breakin you should be getting better efficiency than an original motor with carboned up rings and worn pistons.

Make sure to install new fuel pumps, rebuild the carbs and check for correct jetting and float levels. Pay close attention to the engine timing and synchronization of the carb linkage to timing advance. Prop the engine to reach WOT in the mid to upper half of the operating range. Take time to adjust the idle screws accurately, not just setting them all at the same number of turns open. Good luck.