1988-1995 Mercury Force 5HP Outboards Service Manual, 90-823263 793, Page 205Get this manual
2 Inspect propeller shaftLook for: Wear or distortion around clutch slot (A) and propeller pin hole (8) Sharp burrs or nicks; remove with file or emery cloth Cracks on splines (C)
NOTE: Do not remove excessive metal from shaftInspect clutch spring Check length: 2.4 in(60.9 mm) Check for straightness by rolling on flat surface