Crankshaft And Bearing Removal

Special Tools 

EN-571-B  Dial Gauge

For equivalent regional tools, refer to Special Tools .

Fig 1: Lower Crankcase And Bolts
Courtesy of GENERAL MOTORS COMPANY
1. Remove the 11 lower crankcase bolts M8 (3).
2. Remove and DISCARD the 10 main bearing bolts M10 (2).
NOTE:

Carefully detach the lower crankcase from the engine block, using a suitable tool.

3. Remove the lower crankcase (1).
Fig 2: Measuring Crankshaft Axial Play
Courtesy of GENERAL MOTORS COMPANY
NOTE:

The check is conducted with the crankshaft bearings installed in the cylinder block and the flywheel/automatic transmission flex plate is removed. The crankshaft is only loosely fitted in the cylinder block.

4. Install the EN-571-B  dial gauge (2) with the bracket (1) to the timing side of the engine block.
NOTE:

If the value for the crankshaft axial play does not correspond with the permissible axial play, regrind the crankcase seat and use suitable oversize thrust bearings. For oversize thrust bearings, refer to Engine Mechanical Specifications .

5. Measure the crankshaft axial play. For permissible axial play, refer to Engine Mechanical Specifications .
Fig 3: Crankshaft And Bearings
Courtesy of GENERAL MOTORS COMPANY
NOTE:

Mark the installation position of the crankshaft main bearing. Lay aside in order removed.

6. Remove the 5 crankshaft lower main bearings (2) from the crankcase.
7. Remove the crankshaft (1).
NOTE:

Mark the installation position of the crankshaft main bearing. Set aside in order removed.

NOTE:

The middle crankshaft main bearing contains the thrust bearing (3).

8. Remove the 5 crankshaft upper main bearings (3, 4).
9. Check the crankshaft and bearings. Refer to Crankshaft and Bearing Cleaning and Inspection .