On Wed, 04 Jul 2012 07:20:26 +0700, Bruce
wrote:

On Tue, 3 Jul 2012 17:02:57 -0400, "Tom" wrote:

Thanks Bruce

I took the motor for a spin on the weekend, thought it would clear the clog
and I ran some SeaFoam through it but it did nothing to improve the lower
idle. Higher speed the motor didn't miss a beat, but slowing the throttle
down it wanted to stall and pulling the choke was stopping the stall. But
nothing corrected the issue. Looks like I will have to remove and clean the
carb.

Is there any procedure for setting those idle screws? Other than where they
are now, I would hope they are in the right spot.

Anyone have any ideas where those screws should be? I can do what you
suggest Bruce and count the turns and put back in same spot, but what if
that spot is wrong spot?

Some utube videos say tighten the screw then come back 1.5 turns.

Thanks for the ideas


Idle speed or mixture is not really that important an adjustment as it
is effective only in the idle range. If you had no idea at all you
could just get the engine running and holding the RPM above the idle
range make an adjustment. Retard the throttle until the RPM falls into
the idle range and see whether the engine runs smoothly. If it doesn't
try a different adjustment, either open a bit or closed a bit. The
Idle Speed do the same. Get it to run. Make a preliminary adjustment
and see how it goes, adjust to taste :-)

If you have some doubt about the present adjustment why not change it?
A quarter - half a turn in either direction. See how it goes. You can
always return to the original setting.

It is not like the adjustment is some secret setting. Either the
engine will run smoother, or not as smooth (smooth is good) and almost
anyone should be able to figure out is it better or worse.


More to the above. A mate who services most of the outboards in the
Marina casually mentioned a 9.9 HP O.B. he was servicing. I asked him
what sort of carburetor it had on it and he said that it was just a
simple one - no hidden traps or problems and wondered that "the guy"
had been so long at taking his apart and cleaning it :-)