when you take the cover off, look at the cam shaft gear, it has a hole on each side, and a hole on the top ,that will be the time to do the valves, it only comes around every two turns, of the crank, and that is Top Dead Center,. did you make a tool to hold the adjustment bolt a square hole screw about 1 1/2 inch long , it fits a # 2 Robertson screw driver,. (home depot should have them,) and get a wire connecter called mar connecters, to hold the screw firmly