Tools Required

J 8087 Cylinder Bore Gage

1. Remove all thread sealant, gasket material or sealant using a commercially available plastic or wood scraper.
2. Clean all the following areas with a suitable solvent:

•	Sealing surfaces

•	Cooling passages

•	Oil passages

•	Bearing journals

3. Clean all threaded and through holes with a suitable solvent.
4. Dry the engine block with compressed air.

Measuring Cylinder Bore Diameter

1. Measure the cylinder bore diameter 37 mm from the deck face (1) using a commercially available bore gauge or J 8087  (2).

Important: If the cylinder diameter exceeds the specifications, the cylinder block may be oversized to 0.25 mm. Only one size of oversized pistons and rings are available for service. If the cylinder bore diameter exceeds specification by more than 0.25 mm, the cylinder block must be replaced.

2. Record the results and compare with the dimensions listed in the specifications.

Measuring Cylinder Bore Taper

1. Measure the cylinder bore along the thrust surfaces, perpendicular to the crankshaft centerline, at 10 mm below the deck surface and record the measurement.
2. Measure the cylinder bore along the thrust surfaces, perpendicular to the crankshaft centerline, at 100 mm below the deck surface and record the measurement.
3. Calculate the difference between the two measurements. The result will be the cylinder taper.
4. Compare the results with the dimensions listed in the specifications. Refer to Engine Mechanical Specifications.
5. If the cylinder diameter exceeds the specifications, the cylinder block may be oversized to 0.25 mm. Only one size of oversized pistons and rings are available for service. If the cylinder bore diameter exceeds specification by more than 0.25 mm, the cylinder block must be replaced. Refer to Engine Mechanical Specifications.

Measuring Cylinder Bore Out-of-Round

1. Measure both the thrust and non-thrust cylinder diameter at 10 mm below the deck. Record your measurements.
2. Calculate the difference between the two measurements. The result will indicate out-of-round at the upper end of the cylinder.
3. Measure both the thrust and non-thrust cylinder diameter at 100 mm below the deck surface. Record your measurements.
4. Calculate the difference between the two measurements. The result will indicate out-of-round at the lower end of the cylinder.
5. Compare your results with the dimensions listed in the specifications. Refer to Engine Mechanical Specifications.
6. If the cylinder diameter exceeds the specifications, the cylinder block may be oversized to 0.25 mm. Only one size of oversized pistons and rings are available for service. If the cylinder bore diameter exceeds specification by more than 0.25 mm, the cylinder block must be replaced.

Deck Flatness Inspection

1. Ensure the engine block decks are clean and free of gasket material.
2. Inspect the surface for any imperfections or scratches that could inhibit correct cylinder head gasket sealing.
3. Place a straight-edge diagonally across the cylinder block deck face surface.
4. Measure the clearance between the straight-edge and the cylinder block deck face using a feeler gauge at 4 points along the straight-edge.
5. If the warpage is less than 0.05 mm, the cylinder block deck surface does not require resurfacing.
6. If the warpage is between 0.05±0.20 mm or any imperfections or scratches that could inhibit correct cylinder head gasket sealing are present, the cylinder block deck surface requires resurfacing.
7. If resurfacing is required the maximum amount that can be removed is 0.25 mm.
8. If the cylinder block deck surface requires more than 0.25 mm material removal the block must be replaced.