Good at idle, no power under load

[rkt10000]

I have a '62 10hp Evinrude on my 13' aluminum jonboat. Motor has new ignition parts and the carb has been rebuilt with new needles, seats, gaskets, etc. Has good compression on both cylinders. She runs great in the tank and at idle in the water BUT when under load she runs like crap. No power, skipping. Prop is original but is still in decent shape. I am at the end of my knowledge rope. Oh yeah, I had to use an aftermarket fuel pump.

 

[Rick.]

Re: Good at idle, no power under load

New parts are usually an indication of things being ok but not always. I would test your spark with an air gap tester set for approx.3/8 of an inch. Sounds like you could be running on one cylinder. Best of luck. Rick.