Mercury Optimax Models 135, 150, Direct Fuel Injection., Page 445Get this manual
LEFT HAND NON-RATCHETING
12If backlash is less than the specifications, then larger shim should be installedConversely, if the backlash indicated is greater than specifications, then smaller shim should be installed
NOTE: By adding or subtracting 0.002 in(0.051 mm) shim, the backlash will change approximately 0.002 in(0.051 mm)
aShim 13If forward gear backlash is within specifications, then Bearing Preload Tool, Dial Indicator, Backlash Indicator ToolDial Indicator Holder, PVC pipe, forward gear assembly, bearing adaptor, bearing carrier and test propeller shaft can all be removed from the gear case