I have a 1975 johnson 25hp, on the bottom of the bowl there is a orifice plug does this plug get seated all the way or is there a recommended setting for it? Also what is a good starting point to set the slow speed needle?
The orfice plug goes all the way in. The orfice must be absolutely clean. The size of the hole meters the correct amount of fuel supplied to the engine.
One and a half turns for a beginning point on the slow speed needle
