Yamaha Outboard Motors Factory Service Manual F6 and F8, Page 132Get this manual

LOWER UNIT CHECKING THE LOWER UNIT (FOR AIR LEAKS)
Check: Lower unit holding pressure Check the seals Pressure drops and components
Lower unit holding pressure: 100 kPa (1.0 kgfcm214.2 psi) for 10 seconds Checking steps:

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