2000 25 ELH 0t093926 : sat up for about 3 years and had gummed up carb and fuel lines. So I had long time merc mechanic rebuild carb, new fuel pump diaphram and primer injector. Cleaned plastic 6 gallon tank, new fuel line and primer bulb, new ngk plugs and 100% gas. Still hard to start unless I remove cowling and move the throttle a little. After running for a few minutes you can shut off and it will crank back up with a touch of the start button and even with a short pull on the rope start but if it sets 10 min it is hard to start again. This motor was never hard to start before setting up for such a long period. The black plastic primer knob is supposed to increase the rpm for cold start and trolling and is moving some linkage on the carb but it does not increase the rpm at idle. Should I be able to see the throttle shaft move when the knob is turned? Could it be that the plastic knob is worn enough to cause this problem or has something been left out or disconnected?