69 Evinrude 6hp high rpm bogging

[daveman927]

I'm having an issue getting rpm's at WOT. I have a small 12' sea nymph. Probably weights 90lbs. It doesn't seem like the motor is getting to high rpm's. Definitely not getting the boat on plane & I feel like it should. The carb has be rebuilt, leaf valves replaced, head gasket, plugs, wires, coils, condensers, points.

The only thing different I've noticed is it has a 3 blade 8x7 instead of the 2 blade 8x7 prop. Could this be my issue?

 

[racerone]

Find a shop that may have a test prop.----One way of finding out if motor is producing rated power.

 

[daveman927]

So just an update. I ran it in a 50gal barrel with water & still the same until it cavitated & then it pulled some rpm's. I bought a gauge to measure rpm on the motor & it shows 3k wot in gear. So the boat isn't too big for the motor because it can't even ramp up on its own. I checked timing and both cylinders were spot on through the throttle. Plugs don't look fouled out so it's not too much gas

Is a 3 blade 8x7 too much for these motors?

 

[racerone]

Your test is flawed.----There is a reason they made special; test props.----I have some of them.

 

[daveman927]

I'll look into a test prop. I've never heard of them before. Is there a part number that I could look for?