1998 Mercury 9.9/15HP 4-stroke outboards factory service manual, Page 301Get this manual
BIG FOOT
NOTE: flat washer is located on the shift shaft near the top of the shaftThis washer may slide off shift shaft when gear case is removedDo not lose washer as washer is necessary for reassembly
a-Flat Washer 5Remove four screws and remove gear housing56804