1982 Evinrude 115 Issues

[Bcs-extreme]

My buddy just bought a 1982 Skeeter bass boat with a 1982 Evinrude 115 outboard on it without having it looked at first.
I rebuilt the carbs, installed new plugs, checked spark, made sure the advance was working properly, and it has 118 psi on 1 and 3 cylinders and 128 on 2 and 4 cylinders.
We took it out for about 3 hours and it will only plain out if i get in the bow of the boat and then it will only top out at 34 mph. We went thru 10 gals of fuel and when i checked the plugs they were fuel soaked.
Anyone know what direction to lead me in? and the prop is a 13 1/4 x 20.
Thanks!

 

[Bcs-extreme]

Re: 1982 Evinrude 115 Issues

Also I have not put a tach on the engine but by ear it sounds good, it doesnt lug or sound to rev to fast at full throttle. And it will fire up and idle all day long with no hesitations.
Thanks

 

[emdsapmgr]

Re: 1982 Evinrude 115 Issues

You probably have too much pitch on the prop. That engine rated at the prop is probably only 105 hp by today's measurement standards. Those bass boats are not usually considered light boats, with livewells, extra batteries, etc. On that boat, you may need to go down in pitch. Try a 17 pitch prop and see if you have any better luck. Your engine should be propped to run right at 5500-5700 rpm's. Anything less and you are lugging it.