? for Evi 30hp on a john boat

[TNDOC]

Evinrude 30hp that runs fine most of the time. Every once in a while and some times not at all (variable from trip to trip) the motor will run rough and will not go past 1/4 throttle. Won't even get out of the hole when it is doing this, but once at 1/4 throttle it runs smooth. I have no idea what is going on, I recently changed the tank and fuel line so they are knew. When you try and throttle it wide open it revs up and down, go back to 1/4 throrttle crawl runs fine. Won't idle very well though. Really weird!

If I stop the motor and let it sit a bit, sometimes it does it again, other times it does not. Always starts right up though. Any ideas?

I haven't had it strand me yet and have been using it, but it is frustrating when you are heading home and it starts these antics.

 

[Jason F-18]

It sounds like an ethanol problem. Make sure you are using stabilizer ffor ethanol gas, or get ethanol free for it . If t is the fuel, you will need to drain the carb and spray some carb cleaner througt it. try it again with fresh gas.

The other thing I first thought of is that you have a kink in your fuel line or it is not connected all the way to the tank or motor. This would allow it to get enough gas when idling, but would kill it as soon as you gave t full throttle. I'm sure Wrenchin or someone else can give some more ideas.

Good luck!

 

[KYBoy]

I have a 40 HP that did the same thing. I changed out the fule connection to the motor and the spark plugs and has run great ever since. You may want to give thata try.