Usually if you cant get it to idle right with the adjustments the carb is fouled or the motor is sucking air someplace. Try these adjustments first. Clean and rebuild carb.
Carburetor Adjustments - Two Adjustable N/Vs)
(J. Reeves)
Initial settings are: Bottom high speed = seat gently, then open 1 turn out. Top slow speed = seat gently, then open 1-1/2 turns.
Setting the high and low needle valves properly:
NOTE: For engines that DO NOT have a shift selection, obviously there is no NEUTRAL position. Simply lower the rpms to the lowest setting to obtain the low speed needle va /lve adjustment.
(High Speed) Start engine (it will run pretty rough), shift into forward gear, take up to full throttle. In segments of 1/8 turn, wating for the engine to respond between turns, start turning in the bottom high speed needle valve. You'll reach a point whereas the engine will either start to die out or spit back (sounds like a mild backfire). At that point, back out the needle valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest setting.
(Low Speed) Slow the engine down to where it just stays running. Shift into neutral. Again in segments of 1/8 turns, start to turn the top needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running. Eventually you'll hit the point where the engine wants to die out or it will spit back. Again, at that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.
When you have finished the above adjustments, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.
Disregard the high speed adjustment as it is fixed on a 9.5
The "timing" is more of a sincronizing of the carb and magneto plate. Theres a mark on the spark advance cam, line the cam follower up with this mark. Once there, loosen the screw on the end of the throttle shaft. Hold that little nub against the cam follower which holds the follower againts the timing mark. Tighten the throttle shaft screw. That should do it. Sounds easy.
If that doesnt work, look at your upper crankshaft seal under the magneto plate. If theres oil present near that area, the seal may need to be replaced. The other place that can cause trouble is the throttle shaft itself. Run the motor and then spray seafoam, carb cleaner... where the shaft goes into the body of the carb. If the motor changes RPM you've got a leak.
