91' force I/O idle vs carb

I have a 120 force i/o l-drive and runs great when im on the gas but when going to idle it dies. Seems to die more after its been warmed up. My question is when do I adjust the mixure screw on the carbs vs the idle screw. Just to make my self clear, it runs great when its gassed, its just when i put it in neutral. thanks for your time

Re: 91' force I/O idle vs carb

What is your idle RPM is the deciding factors which screw will be adjusts. If the engine use to idle perfectly, the most likely culprit is a blocked idle port. Or if you recently did some maintenance on the throttle linkage, then it could be the idle screw.

If idle RPM with gear disengaged is around 1100-1200 RPM on driveway, but the engine dies as soon as you disengaged, try adjusting the idle mixture first by turning 1/8 turn CCW. The RPM should go up a tad if not try another 1/8 turn and if it still would not go up, then the idle screw is set to far in meaning the engine is idling on the main jets instead of the idle jet.

Back off the idle screw as required and go back to the idle mixture screw until you can verify the engine is idling on the idle circuit. Then read the sticky above about setting proper idle.

Re: 91' force I/O idle vs carb

Base starting position.The air screws 3 on the side of the carb.Start at 1 turn out from lightly seated.
The towershaft controls the RPM's.About 1150-1200 in the driveway.
In gear in the water 750-800.
Start with cleaning the carb.
Make sure all the tiny holes are clear.
Then rebuild the fuel pump.Usually needs just the diaphram.
Then install a filter between the carb and the pump.
Wally World G2 or G12 depending on the hose size.