Air or gas screw evinrude 30HP ´90

[rocketman007]

Can anyone tell me, if the screw for air/gas mixture controls more air with constant gas or constant air with more gas. What direction makes the ratio rich (turn right or left)?<br /><br />The motor is doing something strange: 3 weeks ago we had problems, because in full throttle it gets to less gas, till it stopped. The Motor started some seconds later without any problems, only in full throttle he died again. When i pumped with the ball, everything was ok, the motor worked fine even in full throttle for long time. When I stopped pumping, it dies again. Last week I cleaned the carburetor, then everything was ok. The hole day nothing, and we drove a long time with full throttle. On Sunday I drove about 30km down the river, on the way back the problem occours again. Only with pumping it was possible to get back to starting-point. Qestion: is ist correct, there´s no air filter in front of the carburator, but there are holes for screws. Is it dirt, from air or gas? Is the fuel pump defective? Any suggestions?<br /><br />Many thanks, Volker

 

[Hooty]

Re: Air or gas screw evinrude 30HP ´90

My guess is the fuel pump needs rebuilding. When you pump the bulb, you are doing the work of the fuel pump. At lower speeds the fuel pump can supply sufficient fuel but at wfo it can't supply the demand.<br /><br />The air flow is constant. screwing the needle in (cw) leans the mixture.<br /><br />c/6<br /><br />Hooty