Measuring Procedure

Engine Block Flatness Inspection

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   Inspect the engine block as shown for distortion. Use a straightedge (1).

2. Courtesy of GENERAL MOTORS COMPANY

   Inspect the engine block as shown for deflection. Use a straightedge (1).

Cylinder Sleeve Diameter Inspection

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   NOTE:

   If the cylinder sleeve measurements are not within the recommended limits, ream the cylinder bores with the recommended oversize. Refer to Engine Mechanical Specifications .

   Inspect the cylinder bores using the EN-8087  gauge (1). Inspect for the following items:

   • Wear of cylinder sleeve
   • Cylinder sleeve diameter
   • Tapering of cylinder sleeve
   • Oval status of cylinder sleeve

     Refer to Engine Mechanical Specifications  for the recommended limits.

Bearing Bore Diameter In Cylinder Block Inspection

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   Install the 10 lower crankcase locating pin, if they was removed.

2. Install the crankshaft to the engine block (4).
3. Install the lower crankcase (1).
4. Loosely install the 10 main bearing bolts M10 (2).
5. Loosely install the 11 lower crankcase bolts M8 (3).
6. Fig 1: Identifying Main Bearing And Lower Crankcase Bolts With Tightening Sequence

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   CAUTION:

   Refer to Fastener Caution .

   CAUTION:

   Refer to Torque-to-Yield Fastener Caution .

   Tighten the 10 main bearing bolts.

   1. Tighten the bolts (1-10) a first pass in sequence shown to 50 N.m (37 lb ft).
   2. Tighten the bolts (1-10) a second pass in sequence shown an additional to 90 degrees, using the EN-45059  meter.
   3. Tighten the bolts (1-10) a final pass in sequence shown an additional to 90 degrees, using the EN-45059  meter.
7. Tighten the 11 lower crankcase bolts (11-21) in sequence shown to 34 N.m (25 lb ft).

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   Inspect the bearing bore diameter in cylinder block using the EN-8087  gauge (1). Refer to Engine Mechanical Specifications  for the recommended limits.

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   Remove the 11 lower crankcase bolts (3).

10. Remove the 10 main bearing bolts (2).
11. Remove the lower crankcase (1) from the engine block (4).
12. Remove the 10 lower crankcase locating pin (5), if they was removed.