1998 Mercury 9.9/15HP 4-stroke outboards factory service manual, Page 234Get this manual
CLAMPSWIVEL BRACKETSDRIVE SHAFT HOUSING
Driveshaft Housing Cover RemovalInstallation
1Remove driveshaft housing covers (4 screws and nuts)
NOTE: To aid in removal of screws, small straight screwdriver should be placed in nut pocket to prevent turning of nuts
a-Driveshaft Housing Covers b-Screws (4), Nuts (4) 2Install driveshaft housing covers (4 screws and nuts)Driveshaft Housing Cover Bolt Torque 30 lb-in(3.4 Nm)