Ok – First I tried hard not to post this…but my trial and error approach simply is not working.  This is a recently rebuilt 1956 Johnson Javelin 30HP that for the most part is running absolutely awesome – that in and of itself has been a journey but very rewarding.

The issue I am facing is that I cannot get the motor to run at full throttle and I have exhausted everything I can trying to use the High Speed knob to make adjustments.  I use a phone app to track speed so will use that to explain the problem.  If I set the throttle at 19/20mph I can pretty much go forever, but if I go full throttle which runs between 24-26mph, I can only go for 30 seconds before the motor starts dying. If I hit some wakes or choppy water that also seems to trigger this behavior.  I would describe it like the motor is starving for gasoline and always have to pump the bulb to re-pressurize the gas line.  If I go back to 7/8mph I can then come back and go full throttle for a brief period.

Admittedly I am new to this and every single stage has been a learning experience which has challenged me.  I am definitely on the path to becoming Mechanic #1 for this motor!!!  There just feels like there is another adjustment I need to focus on that I haven’t even tried and thought I would reach out to this awesome community.  My last post yielded a perfect answer to my last problem… 🙂

Appreciate in advance your advice and counsel.

Rich

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Geer Pyron