'68 Johnsonn FD-22M 20Hp Throttle Stop Screw Adjustment

[bassin'frog]

Dumb question, but haven't been able to find the answer to this: What is the purpose of what I believe is called the Throttle Stop Screw? It is part# 84 on the L/U Diagram on Crowley Marine & MarineEngine. Also, if it needs adjustment, can you explain the adjusting procedure to me....Thanks in advance to all help.

Bob

 

[kfa4303]

Re: '68 Johnsonn FD-22M 20Hp Throttle Stop Screw Adjustment

HI Bassin'frog. If you mean the idle set screw at the base of the vertical throttle tower, it is used to help dial in the idle and/or allow the mntor to be shut off by simply retarding the timing (turning down the throttle) until the motor dies. Some folks like for the motor to die when they twist the throttle all the way down, others do not. By twisting the screw in, it advances the timing slightly and raises the rpm, while backing it out retards the timing and lowers the rpm. The trick to a nice smooth idle and powerband is to find a balance between the Lo speed needle on the carb and the idle set screw.

 

[bassin'frog]

Re: '68 Johnsonn FD-22M 20Hp Throttle Stop Screw Adjustment

kfa: that was exactly what I was looking for. Thanks much for the assist, appreciate it.