My yamaha 9.9 motor pushes my boat at lower rpms but the prop seems to slip at higher rpms. though it was shear pin but cant find one in the lower end. any help would be great thanks UD.
Sounds like you have a "spun prop". The inner hub and the outer part with the blades on it are put together with a "rubber bushing" type assembly, which can fail and it's like a slipping clutch. You can have the prop rebuilt or buy a new one. Good Luck!
