2001-2002 Yamaha 50HP F50Z/T50Z Ouboard 4-stroke engines service manual, Page 230Get this manual
Backlash (F50F50A) 5Slowly turn the drive shaft clockwise and counterclockwise and measure the backlash when the drive shaft stops in each directionSlowly turn the drive shaft clockwise and counterclockwise and measuring the backlash when the drive shaft stops in each direction
Forward gear backlash: 0.18-0.54 mm (0.007-0.021 in)
Add or remove shims if out of specificationForward gear backlash Shim thickness To be decreased by (0.36M) 0.56 To be increased by (M0.36) 0.56
Less than 0.18 mm (0.007 in) More than 0.54 mm (0.021 in) M: Measurement
Available shim thicknesses: 0.10, 0.12, 0.15, 0.18, 0.30, 0.40, and 0.50 mm
Remove the special service tools from the propeller shaftApply load to the reverse gear by installing the propellerwithout the spacerthe washer backwards, then the washer as shownReverse gear backlash: 0.71-1.07 mm (0.028-0.042 in)