5hp johnson seahorse

[lyncraft_mechanic]

I have a 1967 5hp seahorse outboard I recently purchased and just ran for the first time the other day. it started on the first pull of the recoil but after just two days of running on the pond it would only run on half choke! since then i have cleaned & rebuilt the carb and it was back to starting on the first pull of the recoil but this motor does not seem to be achiving max. rpm. i have tried adjusting the needle valve but the motor still runs strong no matter if i lightly seat it or back it out 5 turns. does anyone have any suggestions or know what to look for? perhaps a vacum line??????????????

 

[tashasdaddy]

Re: 5hp johnson seahorse

Welcome to iboats. a manual will help. link n sinc. correct carb adjustment. select from these: http://forums.iboats.com/showthread.php?t=167352

 

[gejandsons]

Re: 5hp johnson seahorse

If changing from seated to out 5 turns has no effect, I think something is plugged up in your carb.

 

[lyncraft_mechanic]

Re: 5hp johnson seahorse

today i took off the carb cleaned it again, blew it out with compressed air and run the motor but no difference. this motor has an adjustable low speed and a fix high speed jet. do you think if i replaced the high speed jet that it would make much of a difference?

 

[Xcusme]

Re: 5hp johnson seahorse

.... do you think if i replaced the high speed jet that it would make much of a difference?

Probably not, if the low speed needle adjustment has no affect on motor RPM's at idle, you still have either a low speed fuel delivery circuit problem or a gasket (typically the Boss gasket) not sealing. Typically , if the Boss gasket is leaking, the motor won't idle well, too much fuel will be drawn into the motor and run very rich at low speed. Did you remove, clean passages, and replace the small aluminum disc on carb top? Replace needle packing etc to eliminate vacuum leaks? It sounds like you'll need to throughly soak carb and blow out with compressed air.

 

[F_R]

Re: 5hp johnson seahorse

Xcuseme has it nailed. The slow speed adjustment has little or no effect on high speed running, which seems to be your complaint. Also, if the soft gasket between the main body and float bowl is leaking, it effectively bypasses the main orfice jet. That orfice has to be absolutely clean. Nothing else will do.