Im having trouble starting my 94' johnson 150. The deal is, it will start at the house with the muffs on, i can start it at boat ramp unload go fish a spot then it wont fire. It doesnt try to turn over or nothing just dead. It takes anywhere from 5 to 30 turns on the ignition for it finally start. if it starts at all, kinda hit or miss. Last time i couldnt get it to fire, i raised the motor took the cover off as if i knew what the heck to do, stared at it for a min, turned the ignition and it fired right up. So, i dont know if its the starter, ignition, wiring maybe... Im a novice when it comes to boat motor maintenance, Any help or ideas would be greatly appreciated, Thanks guys

this happened to me. Never figured it out and one day it just stopped doing it and (knock on wood) won't do it again!

I assume when you say it won't turn over you mean the starter will not spin.

Could be:

1. Kill Switch
2. Control not in neutral
3. Loose battery cable, ignition wiring or bad connector.
4. Bad Cranking Battery
5. Starter Solenoid
6. Ignition switch

check your bulb in the fuel line, if it is not hard after running then you may have an air leak or are losing fuel in the bowls as it sits. try pumping the bulb next time it won't fire and see if it tries.

has the fuel pump been rebuilt?

if it is trying to turn over and just not starting it is probably fuel related.