Hello everybody...I am working on a 1990 Johnson 9.9 that has 120 PSI in both cylinders, runs smoothly in gear to full throttle and idles nicely in gear. The problem is that while in neutral there is virtually no twist available in the tiller throttle to even slightly increase the idle speed which seems too low. It is hard to start and keep running while cold because of the low idle speed unless I quickly put it in gear so I can raise the engine speed just a little bit to keep it running. After it is warn it will idle in neutral for a couple minutes before it eventually stalls. There is a knob on the front of the motor ,to the right of the choke lever, that I am assuming is an idle speed adjustment but it has no effect no matter haw far it is turned in either direction. I was hoping for a mechanical idle speed screw to adjust idle speed but haven't found it and the manual I have is very vague. We did find a few pieces of broken whitish colored plastic in the valley under the carb...the pieces look to have been a round bushing at one time maybe from that round roller that moves along with the throttle and follows the horizontal sloped metal plate just under the flywheel to change the ignition timing as the throttle input changes. Any input will be greatly appreciated. Thanks in advance and Happy Boating.
