Evinrude 15 late 80's prop lower unit cativation

[thatone123]

I gopt this outboard because I wanted to try and electric start again. Have lots of experience with these outboards and have tried many different props but am stumped by this problem. Use it on a 12 ft. Johnboat which allowed me to get into remote places. 2 Weeks ago when I used it last I noticed that what seems to be the standard prop would lose bite in the water. I tried different trims, weight distribution etc. Once I got on step it seemed OK and ran fairly normally. Today I had a person in the boat and it was terrible. Once I got on or near plane, the prop seems to slip like a bad clutch in a car. After a long while of going at displacement speed, I got the motor up to about half speed for a while, before the prop (or gears?) would let loose and I would loose speed and bite and/or gear proper operations. I have used this type boat with this type motor with many prop variations and trim and have never come across this. Familiar with gear working and don't see how gears could cause this or am I wrong? I tried all the trim angles, weight distribution and no big difference as it still does this no matter what I do?

 

[flyingscott]

Your prop has a spun hub. Try a different prop.

 

[Bullie]

Converging ring issue maybe?

 

[thatone123]

Yes, I am considering both of these. The prop is some kind of after market cheapie it appears with no pitch or diameter info on it. It is like new so I don't think it was a spun hub, but maybe. The convergence ring lack of usually does not act up this bad, but could be a contributing factor. Will try out old proper OMC prop today. The prop is large on the big side for a 15 hp and I did have some of these same slip problems with an old OMC large diameter prop, but not like this. Wondering if this prop could be for a larger outboard? I was 8 miles down a slow moving stream with this. Some may want to know that going up stream you can usually get on plane better because the current pushes the boat up on plane more easy. I'd still be down there if I was not able to get it on plane once in a while.