I just purchased a 1980 Evinrude 25 HP with tiller steering and throttle. After lubing the cylinders and cleaning the carb the motor started effortlessly. There are a few minor issues to deal with, the first of which is the fact that the motor dies when I idle down to the shift RPM level. I have no idea how long the unit sat before I bought it. The motor sounds so strong with the throttle open, or even just a little bit open, but I obviously can't even test the gear box when I can't shift it. There is a strong stream of water being expelled by the impeller, and it was really smokey at first until the extra lube oil burned off. We've tried adjusting the lean/rich screw all through its travel, but with only minor difference. Is there any other way to adjust a 2 stroke carb? I had to jury rig the fuel supply by hooking directly into the fuel pump(I don't have a fitting). Could this be a part of the problem? What else could I check? Sorry to ask so many questions, but this is only my second outboard motor and my first 2 stroke. Thanks for your help!!