Crankshaft and Bearings Cleaning and Inspection

Tools Required

• J 45059  Angle Meter
• KM-470-B  Angular Torque Gage

Fig 1: Checking For Crankshaft End Play
Courtesy of GENERAL MOTORS CORP.
1. Coat the crankshaft bearings with engine oil.
2. Install the upper crankshaft bearings into the engine block crankshaft journals.
3. Install the lower crankshaft bearings into the crankshaft bearing caps.
4. Install the crankshaft.
5. Inspect the crankshaft end play with the crankshaft bearings installed.
6. Check for permissible crankshaft end play. Refer to Engine Mechanical Specifications .
Fig 2: View Of Middle Crankshaft Journal Runout Check
Courtesy of GENERAL MOTORS CORP.
7. With the crankshaft mounted on the front and rear crankshaft bearings, check the middle crankshaft journal for permissible out-of-round, runout. Refer to Engine Mechanical Specifications .
Fig 3: View Of Plastic Gaging Thread On Bearing
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: Grease the crankshaft journals and lubricate the crankshaft bearings slightly so that the plastic gaging thread does not tear when the crankshaft bearing caps are removed.
8. Inspect all of the crankshaft bearing clearances using a commercially available plastic gaging, ductile plastic threads.
9. Cut the plastic gaging threads to the length of the bearing width. Lay them axially between the crankshaft journals and the crankshaft bearings.
Fig 4: View Of Torque Wrench And Special Tool
Courtesy of GENERAL MOTORS CORP.
10. Install the crankshaft bearing caps.
NOTE: Refer to Fastener Notice .
11. Install the crankshaft bearing cap bolts.

    Tighten:  Tighten the crankshaft bearing cap bolts to 50 N.m (37 lb ft)  , using the J 45059  or the KM-470-B  (1), tighten the crankshaft bearing cap bolts another 45 degrees plus 15 degrees.

Fig 5: Measuring Plastic Thread Using Scale
Courtesy of GENERAL MOTORS CORP.
12. Remove the crankshaft bearing caps.
13. Measure the width of the flattened plastic thread of the plastic gaging using the scale printed on the plastic gaging package. Plastic gaging is available for different tolerance ranges.
14. Inspect the bearing clearances for permissible tolerance ranges. Refer to Engine Mechanical Specifications .