Mercury Mariner 4 and 5HP 4-Stroke Outboards Service Shop Manual 1999, Page 147Get this manual
CYLINDER BLOCK AND CRANKCASE
Measuring Diameter of Crank Pin" A"
Standard Value Out of the Limit
1.179 in(29.94 mm)
If 1.177 in(29.91 mm) or less requires
replacement
Measuring Outer Diameter of Crankshaft in the Oil Pan BearingB"
Standard Value
Out of the Limit
0.963 in(24.96 mm)