Re: Lower unit leak
The concern with the shims is, did the guy who took it apart earlier (and put the cam follower in backwards) replace the shims and in the right place.
You don't really align the shift cam if that's what you are referring to. As I mentioned, it is free to rotate 360*. It is important that it is installed "right side up". Once you get the whole unit put back together, then you will set it into whatever gear you want for reattachment to the motor. This is done by rotating (CCW only as viewed from above) the shift shaft. As you rotate the shift shaft (CCW only) the unit repeatedly switches between F-N-R-F-N-R etc.