Tool Required

J 36660-A Torque Angle Meter

Important: The upper main bearings have an oil groove and oil holes, the lower bearings do not have oil grooves or oil holes.

1. Install the upper main bearings into the cylinder block and lubricate with engine oil.



2. Install the lower main bearings into the lower crankcase and lubricate with engine oil.



3. Install the 2 upper thrust bearing washers into the cylinder block and lubricate with engine oil.

Important: Install the upper thrust bearing washers with the oil groove facing outward.

4. Carefully place the crankshaft on to the main bearings in the cylinder block.



5. Thoroughly clean and remove any oil residue from the cylinder block mating surfaces.

Important: Try to avoid applying an excessive amount of sealant to the surface.

6. Apply a continuous bead of GM P/N 12346240 or equivalent sealant to the cylinder block mating rails.

Notice: In order to prevent the possibility of cylinder block or crankshaft bearing cap damage, the crankshaft bearing caps are tapped into the cylinder block cavity using a brass, lead, or a leather mallet before the attaching bolts are installed. Do not use attaching bolts to pull the crankshaft bearing caps into the seats. Failure to use this process may damage a cylinder block or a bearing cap.




7. Carefully place the lower crankcase assembly on to the cylinder block.
8. Gently tap the lower crankcase into place with a suitable tool.

Notice: This bolt is designed to permanently stretch when tightened, and therefore MUST be replaced anytime it is removed. The correct part number fastener must be used to replace this type of fastener. Do not use a bolt that is stronger in this application. If the correct bolt is not used, the parts will not be tightened correctly. The system or the components may be damaged.

9. Install the 10 main bearing cap bolts. Finger tighten.




Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

10. Progressively torque the main bearing cap bolts using 3 steps in the sequence shown.

1st Pass
Tighten the main bearing cap bolts to 21 N·m (16 lb ft).

2nd Pass
Tighten the main bearing cap bolts to 43 N·m (32 lb ft).

3rd Pass
After reaching the torque of 43 N·m (32 lb ft). Use a J 36660-A and tighten the main bearing cap bolts an additional 90 degrees.

11. Install the 10 lower crankcase bolts.

Tighten
Tighten the 10 lower crankcase bolts to 18 N·m (13 lb ft).