Rod Bearing


To remove the rod bearings, the engine will have to be disassembled and the pistons and connecting rods removed.

  • If the bearing does not fall out during removal of the pistons, it can be snapped out of the connecting rod easily.
  • Install the new bearing inserts in the rod and cap.
  • The insert bearings for the connecting rods must be the correct size.
  • If the crankshaft has been machined undersize, matching rod bearing inserts must be installed.
  • The size of the bearing inserts is printed on the box they come in and is stamped on the backs of the bearings.
The connecting rod bearing size is marked on the back of the bearing.
  • Some connecting rods have a hole drilled through the big end to the bearing area. The bearing insert might have a hole, which will align with this drilling.
  • Rod bearings are usually offset in the rod bore toward the middle of the crank journal. This is so the edges of the bearings will not rub on the fillets.
  • Bearing spread keeps the bearings in the rod while the pistons are being installed.
    • A good bearing that is going to be reused might have lost its spread.
    • According to Federal Mogul Corporation, bearings can be respread by placing the bearing on a hardwood surface with the parting face down gently tapping the back with a soft-faced mallet.
When a bearing has lost its spread, inspect the piston for evidence of abnormal combustion.

Make sure that the parting surface of the rod cap does not have any burrs or foreign material that might prevent proper mating when torquing.

A burred cap parting surface.
  • Snap the new connecting rod bearing inserts into the connecting rods and rod caps. Make sure the tang on the bearing fits snugly into the matching notch.
Make sure that the bearing tang is properly located before torquing the rod cap. Courtesy of AE Clevite Engine Parts.