Connecting Rod Bearing Selection
Each connecting rod fails into one of four tolerance range (from 0 to 0.024 mm (0.0009 in), in 0.006 mm (0.0002 in) increments) depending on the size of its big end bore.
It is then stamped with a number or bar (1, 2, 3, or 4/I, II, III, or IIII) indicating the range. You may find any combination of 1, 2, 3, or 4/I, II, III, or IIII in any engine.
Big End Bore Size: 51.0 mm (2.008 in)
Inspect the connecting rod for cracks and heat damage.