Engine revs up but won’t push the boat forward.

[Digger4u2nv]

I have an old mercury 7.5 hp outboard. The motor was working fine and then all in a sudden stopped pushing my zodiac forward. The engine would rev up but wouldn’t move the boat. The motor pushes the boat at an idle but does nothing when I give it gas. Is this a sheer pin issue or something worse?

 

[Scott Danforth]

Prop hub most likely

 

[oldman570]

More than likely the shear pin, or slip clutch, is broken if the motor still pushes the boat at idle speed.

 

[Scott Danforth]

mercs didnt use shear pins

so it cant be a shear pin.

or a slip clutch.

if the prop hub rubber slipped, buy a new prop. or drop the lower and inspect the driveshaft to see if it is broke. if it isnt the prop hub or the shaft, its the dog clutches