Mercury Mariner 4 and 5HP 4-Stroke Outboards Service Shop Manual 1999, Page 72Get this manual

TIMING AND SYNCHRONIZATION
4Multi-Meter DVA Tester (a) (91-99750) or DMT 2000 Digital TachometerMulti-Meter (b) (91-B54009A 1)

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