Re: 9.9 Evinrude
when you put it in gear, does it rev up as if it's running full speed, just doesn't have speed?
That's probably a prop problem. turn off the motor, unplug the spark plugs, put it in gear and try to turn the prop by hand; if you can, there's the problem. But even if you can't, it still maybe the problem.
Pull the prop off. If you have a shear pin, there is a 2" or so metal pin going through the shaft under the prop and fitting in a groove on the prop. This is the shear pin, designed to break when you hit something (shear off) instead of your prop blades or shaft. If not, the prop has "bushing" when means it's not solid metal; there is a tight rubber fitting between the hub and the prop itself. On small props it's hard to tell that it's there.
If the pin is broken, or the bushing loose, the shaft spins inside the prop hub and the prop doesn't turn. Since you said "barely moves" I am guessing bushing, AKA "spun hub."
If not, your shift dog or parts nearby is worn out--a part inside the lower unit, basically the transmission.
