[starkyb]

I have a 1972 merc 9.8. While running across the lake the prop started slipping and motor started revving. I could still run it at very slow speeds and the prop would still spin. When I got home and went to remove the prop I noticed that it would slide back and forth on the shaft about a quater of an inch and it looks like a big washer may be missing between the nut, small washer and the prop. With the motor in forward gear the prop will turn and click when turned forward but catches correctly when turned backwards. With motor in reverse it catches correctly when prop is manually turned in both directions. Could a missing washer cause the prop not to engage properly. Please help, thanks.

[Fishstew]

I have the same problem with my 2000 Mercury 25HP. I tried putting a new prop on it. When I try to get up on a plane it slips. The RPM's go up but the boat doesn't go any faster. The prop hub is not slipping and it a 13 pitch prop like the one I removed. It does seen that I have the extra space on the prop shaft like you described ( about 3/4 of an inch)

Please help,

Fishstew