floats

[luckynickles]

i have a fifty classic 1989 mercry outboard (45 ) horse

i cant get it to run right in the water it throttles and runs great out of water starts throttles and runs exceptionally well ive cleaned carbs and so called setting floats whitch i dont think ive done them right , put back in the water wont throttle well like a 25 horse wont get on top can someone help me

 

[CharlieB]

Re: floats

One or two dead cyls will seem to run perfectly on the hose, yet fail miserably on the water.

Troubleshooting any problem should start by verifying the integrity of the motor with a simple compression test to ensure compression on all cyls is within 10% of each other. The actual # may vary depending on the quality of the guage used.

Next, another simple test of the ignition to ensure all cyls have adequate spark to arc a hot blue arc across a 7/16 inch gap.

Once compression and ignition is confirmed then the problem may be a lean idle mixture. Two strokes do not have an accelerator pump to provide the additional fuel necessary for crisp acceleration, instead they rely on an overly rich idle mixture. Idle mixture must be set with the motor IN the water and IN Forward gear to provide both the correct exhaust back pressure and load on the motor turning the prop.

Idle mixture adjustment while on the hose can get close enough to launch the boat but should be finalized once on the water.

Adjust to best idle plus 1/8 turn out, test acceleration once on the water, any hesitation, lean cough, increas idle mixture another screwdriver blade width and retest acceleration again. Repeat to perfection. A heavier loaded boat will require more idle fuel than a lighter loaded boat.