Inspecting the Engine Block Condition

PROCEDURE

1. The block must first be thoroughly cleaned (refer to the Cleaning the Engine Block section).
2. Visually inspect the block for corrosion, cracks and other damage. Check the condition of the bolt hole threads. It is also advisable to test the block for hidden cracks at an automotive service shop using specialized diagnostic equipment. If defects are found, the block must be repaired or replaced.
3. Check the condition of the cylinder bores.

4. Evaluate the taper and out-of-round of the cylinders:

a) Measure the diameter of each cylinder at the top (directly below the ridge of wear), middle and bottom sections in a plane parallel to the crankshaft axis;
b) Now measure the diameters at the same three levels, but in a plane perpendicular to the block axis;
c) The cylinder taper is determined by the difference between the measurements at the top and bottom sections. Out-of-round is the difference in diameter between the directions parallel and perpendicular to the crankshaft axis at each level.
d) Compare the results with the nominal values (refer to Specifications).

5. Using the same method, check all cylinders in turn.
6. If significant defects are found or the measurements deviate from the specified requirements, the cylinder block must be machined at an automotive service shop. If the cylinders were bored during repair, the engine must be fitted with new pistons of the corresponding oversize.
7. If the condition of the cylinder bores is found to be satisfactory during inspection, and the cylinder shape and piston-to-bore clearances meet the specified requirements (refer to the Inspecting Piston and Connecting Rod Assembly Components section), boring of the cylinders is not required. It is sufficient to hone the cylinder bores (refer to the Honing the Cylinder Bores section).

8. Check the flatness of the block surface that mates with the cylinder head. Compare the measurement result with the Specifications requirements and, if necessary, have the block resurfaced.