Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 364Get this manual
6Inspect reverse gear thrust washer surface for wear or taperIf surface is worn or taperedpropeller shaft must be replaced 9Measure propeller shaft FORWARD to REVERSE shoulder lengthIf measurement is under 2.040 in(51.816mm), replace propeller shaft2.040 in(51.815mm)
aThrust Washer Surface
7Inspect the propeller shaft for bent condition
10Inspect REVERSE thrust washer for wear or taperMeasure thickness of washerIf thickness is LESS than 0.240 in (6.096mm), replace washer0.240 in(6.096mm)
aV-Blocks and Dial Indicator
(1 Position the propeller shaft bearing surfaces on V-blocks(2 Adjust the height of V-blocks to level the propeller shaft(3 Position the dial indicator tip just forward of the propeller shaft splines8Rotate the propeller shaft and observe the dial indicator movement, If the indicator in the dial moves more than 0.010 in(0.254 mm), replace the propeller shaft