1989 V4 100XP idle adjustment

[edmaude]

My boat is a few hundred miles away, but I was hoping someone suggest the best way to raise the idle speed. I have recently rebuilt carbs, clean fuel, clean fuel filter and all fuel lines are tight. Yet, I often have the motor cut out on my when running at idle speed in gear and also in neutral.

Thanks
Ed

 

[SparkieBoat]

Re: 1989 V4 100XP idle adjustment

what is idle RPMs in the water? also did you clean the idle passages in carbs good? raising the idle to compensate for a mechanical problem is not the way to go. what is your idle timing and WOT timing?

 

[edmaude]

Re: 1989 V4 100XP idle adjustment

In the water I am around 650RPM. I generally lift the throttle up a bit to keep running at 800 RPM which the engine maintains perfectly in or out of gear.

Not sure on the timing, but the engine runs great across the entire powerband including WOT. Is there a set screw I can access to at least try to bump the idle a bit before I take the carbs out again?

 

[emdsapmgr]

Re: 1989 V4 100XP idle adjustment

At idle the carb butterflys should be closed on that engine. The idle on that engine is determined by the idle timing, not by the carbs. To increase the idle timing, screw that large screw on the spark advance lever clockwise. You set the idle timing at 650-700 rpm's set when the boat is floating normally in the water and the engine is in forward gear. You can't set it on the trailer.