2009 Yamaha F40 Outboard Service Manual, Page 266Get this manual

Drive shaft and lower caseShimming
Shimming
Shimming workflow
Remove the water pump assembly
Shimming is not required
Measure the backlash before disassemblyWithin specification? NO Disassemble the lower unitYES

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