Crankshaft and Bearing Cleaning and Inspection: Notes

Special Tools

• J 7872:  Dial Indicator Set
• J 45059:  Angle Meter

For equivalent regional tools, refer to Special Tools .

Fig 1: Measuring Crankshaft Run Out
Courtesy of GENERAL MOTORS CORP.
1. Clean the crankshaft and bearings.
2. Inspect the crankshaft for the following conditions.
   • Excessive wear or damage on the surface of the crankshaft journals.
   • Excessive wear or damage to the crankshaft gear.
   • Excessive wear or damage on the oil seal fitting surface.
   • Inspect the oil ports for obstructions.
   • Replace the crankshaft if there is excessive wear or damage to the journals, oil seal fitting surface or to the crankshaft gear.
3. Measure the crankshaft run out.
   1. Mount the crankshaft in wooden V-blocks.
   2. Set J 7872:  set on the center of the crankshaft journal.
   3. Turn the crankshaft in the normal direction of rotation.
   4. Record readings. The production value is 0.05 mm (0.0020 in) and the service limit is 0.44 mm (0.0173 in).
Fig 2: Measuring Crankshaft Journal Diameter
Courtesy of GENERAL MOTORS CORP.
4. Measure the crankshaft journal diameter across four points.
   • The crankshaft journal outside diameter is 79.905-79.925 mm (3.1459-3.1466 in) and the service limit is 79.89 mm (3.1453 in).
   • Replace the crankshaft if the measured value is less than the service limit.
5. Measure the crankpin outside diameter across four points.
   • The crankpin outside diameter is 62.902-62.922 mm (2.4765-2.4772 in) and the service limit is 62.88 mm (2.4756 in).
   • Replace the crankshaft if the measured value is less than the service limit.