Rod and Main Bearing Selection

Rod Bearing Selection
1. Inspect each connecting rod for cracks and heat damage.

Connecting Rod Big End Bore Code Locations





2. Each rod has a tolerance range from 0 - 0.024 mm (0.0009 inch), in 0.006 mm (0.0002 inch) increments, depending on the size of its big end bore. It's 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 numbers and bars in any engine. (Half the number or bar is stamped on the bearing cap, the other half on the rod.)
If you can't read the code because of an accumulation of oil and varnish, do not scrub it with a wire brush or scraper. Clean it only with solvent or detergent.
Normal Bore Size: 48.0 mm (1.89 inch)

Connecting Rod Journal Code Location
3. The connecting rod journal codes are stamped on the crankshaft.





Connecting Rod Journal Code Location (Letters or Bars)





4. Use the big end bore codes and rod journal codes to select appropriate replacement bearings from the following table.

NOTE:
^ Color code is on the edge of the bearing.
^ When using bearing halves of different colors, it does not matter which color is used in the top or bottom.


Main Bearing Selection
Crankshaft Bore Code Location





1. Numbers or letters or bars have been stamped on the end of the block as a code for the size of each of the five main journal bores. Write down the crank bore codes. If you can't read the codes because of accumulated dirt and dust, do not scrub them with a wire brush or scraper. Clean them only with solvent or detergent.

Main Journal Code Location





2. The main journal codes are stamped on the crankshaft.





3. Use the crank bore codes and crank journal codes to select the appropriate replacement bearings from the following table.

NOTE:
^ Color code is on the edge of the bearing.
^ When using bearing halves of different colors, it does not matter which color is used in the top or bottom.