87 Johnson 50 Surges at WOT

[Goran]

I rebuilt the carbs recently and when i took it out to try the RPMs would surge when it was at WOT.
up to about 4200rpm was ok, then the surging would start

when i got back to the dock it wouldn't even start, it would just crank

any ideas would be appreciated

Thanks

 

[Bosunsmate]

sounds like fuel restricting or an overheat.
Is your primer bulb firm with engine off?
Try priming the bulb while the you try and start engine, if that doesnt work you will need to check spark and compression before deciding where to go from there

 

[Bosunsmate]

The priming fuel bulb while trying to start acts as a manual pump to check if your pump has failed.
The checking primer bulb holds firm with engine off (but ignition on) checks that you arent getting a carb flooding out.