69 johnson 25 horse idle screw starting point

[lmuss53]

I'm working on trying to clean the carburetor on a 69 johnson 25. Part of the problem is it's idling rough, can somebody to give me a starting point for the idle screw . I'm gonna pull the carb off, hopefully somebody will chime in here.
it is a 25 r69b

 

[boobie]

Re: 69 johnson 25 horse idle screw starting point

Go to the Top Secret File at the beginning of this forum. There's a good procedure in there.

 

[kfa4303]

Re: 69 johnson 25 horse idle screw starting point

Here's the carb set up link. When you say "idle set screw" do you mean lo speed needle? I only ask because there is also an "idle set screw" at the base of the vertical throttle tower and it has no prescribed position as such. It acts as a stop for the twist throttle as well as the idle position of the magneto. Some people like to use it to prevent the motor from dying when the throttle is turned all the way down, others prefer to set it such that the motor will die by twisting the throttle all thew way down. By screwing it in, you advance the spark and raise the rpms slightly, by backing it out you retard the spark and lower the rpms. You can then use the lo speed needle to compensate accordingly until and ideal idle is obtained.

http://forums.iboats.com/showthread.php?t=167352

 

[lmuss53]

Re: 69 johnson 25 horse idle screw starting point

Thank you gents. I mean the idle screw at the top of the carb, but now I know where the screw for the linkage is too. I printed out the Joe Reeves instructions and will take them along when I dunk her in the morning. I found a really gunked up fuel pump so a I did a fuel pump rebuild, added a filter, some new lines, cleaned the carb and I think we're ready to try again. The engine was surging and cutting out at speed as well as idling rough.

 

[lmuss53]

Re: 69 johnson 25 horse idle screw starting point

It worked like a charm fellas idled right down smooth as silk using the Joe Reeves instructions, and ran like a scalded dog with the clean carb. Thanks again.

 

[kfa4303]

Re: 69 johnson 25 horse idle screw starting point

SWEET!!!! Happy boating! Vroom-Vroom!