Description of idle screw

[ToonTides]

I am working on a 1988 Evinrude 9.9 (E10ELCCD) that won't idle. It seems to be missing the idle (timing stop) screw below the flywheel and above the block on the back of the motor. Probably just vibrated out. What I am trying to figure out are the dimensions of the screw, threadpitch, diameter, and length, so I can go get another at the hardware store instead of ordering it, waiting a week, and paying too much. Anyone know what the specs are?

 

[the machinist]

Re: Description of idle screw

I have tinkered with these motors for years & never even knew there was a screw that you are referring to. So I went out & looked at my 1992, had to do a lot of looking & yes under the timing plate on the rear is a threaded hole (looks to be possibly a #10-32 thread). Mine is empty also. I suspect this may have been some engineer's dream & they later decided it was not needed. I have ran this motor considerably for over 8 years & have never missed it not being there.

 

[ToonTides]

Re: Description of idle screw

I have found this screw (or rather the one that's missing in this case) is useful for setting the idle at low speed. Actually its adjusting the timing, but it simlply gives the timing advance a stopping point that is independant of the stop on the control box. I also have been working on these many years and haven't run into one without it until now. If yours doesn't have one how are you setting the idle? At the stop on the control box? Or at that cheesy OMC stop lever on the port side of the powerhead? Those never seemed to work well for me...