How To Select A Main Bearing: Notes

When New Cylinder Block and Crankshaft are Used: 

1. "Main Bearing Selection Chart" rows correspond to bearing housing grade on rear left side of cylinder block.
   • If there is a corrected stamp mark on the cylinder block, use it as a correct reference.
   Fig 1: Identifying Stamping Positions

   Courtesy of NISSAN MOTOR CO., U.S.A.
2. Apply journal diameter grade stamped on crankshaft front side to column in "Main Bearing Selection Chart".
   Fig 2: Identifying Journal Diameter Grade & Reference Code

   Courtesy of NISSAN MOTOR CO., U.S.A.
3. Find value at crossing of row and column in "Main Bearing Selection Chart".
   CAUTION:

   • There are two main bearing selection charts. One is for odd-numbered journals (1, 3, and 5) and the other is for even-numbered journals (2 and 4). Make certain to use the appropriate chart. This is due to differences in the specified clearances.
4. Apply the symbol obtained to "Main Bearing Grade Chart" to select.
   NOTE:

   • Service parts are available as a set of both upper and lower.

When Cylinder Block and Crankshaft are Reused: 

1. Measure inner diameter of cylinder block main bearing housing and outer diameter of crankshaft journal.
2. Apply measurement in above step 1 to the "Main Bearing Selection Chart".
3. Follow steps  3 and  4 in "When New Cylinder Block and Crankshaft are Used".