Mercury Mariner 4 and 5HP 4-Stroke Outboards Service Shop Manual 1999, Page 190Get this manual

GEAR HOUSING
5Remove water pickup seal (a)6Remove water pump impeller (b) o

7Remove insert (a)

Water Pump Base and Shift Shaft

• ATV
• Jet Ski
• Outboard Motors
• Personal Watercraft
• Snowmobiles
• Stern Drives