1985 johnson 25 hp - Help!

[skippjack]

Took my boat out today and when I reached my destination I shut it off. After a few, before getting underway again I was in low water so I tilted the motor up and engaged the shallow water drive and started the engine. At that point it started to race (pretty high rpms - too much to even think about shifting) throttle was all the way back. I shut her down, put the motor back in normal position, started it and it idled fine. Does anyone have any ideas about what can cause this to happen?

 

[kofkorn]

You may have had the motor tilted too much, causing the fuel to sit at a lower level in the carb. When the fuel is lower in the carb bowl, it will make the fuel mixture lean out. A lean fuel condition can cause the motor to race. Seeing that it immediately corrected itself when you lowered the motor, that's what I expect happened. If you had no issue after lowering the motor, I wouldn't worry about it too much.

 

[skippjack]

Thanks that make sense, but when that happened it was only tilted up as much as it should be as the shallow water drive bracket holds it from going down all the way, a little higher than closest pin setting to the motor. I wonder if im having low speed carb issues. runs great at mid range and fully throttle but still a little dicey at low speed. I have a 79 Johnson 6 hp that purrs like a kitten at the lowest throttle position, and I cant seem to get this one to run like that so far.