65 Evinrude Sport twin won't go any faster than Idle speed at full throttle

[steevo1752]

Hello,
I have a 65 Evinrude Sport twin 9.5hp, and I am having problems with the gears. The motor will run wide open but the boat will not move any faster than if it was idling. It is like the transmission in a car slipping. I am not at all familiar with how it all works, so if anyone could help me out I would appreciate it. I was having problems with it slipping out of gear a lot before this happened. Thanks,
Steevo

 

[F_R]

Re: 65 Evinrude Sport twin won't go any faster than Idle speed at full throttle

Simple. Your propeller hub is slipping. You need a new prop. This is a generic picture, but it gives the general idea.

EDIT: The above diagnosis only applies if it is a smooth slip as you describe. But if it is making grinding noises as it "slips", that is serious gear problems inside the lower unit.

 

[steevo1752]

Re: 65 Evinrude Sport twin won't go any faster than Idle speed at full throttle

Thanks for helping me out!