Cylinder Block — Cleaning and Checking (Opel Frontera A)

When completely disassembling the cylinder block, thoroughly clean and remove foreign particles from the cavities and oil channels. Remove all remaining cleaning fluids completely. Please pay special attention to this. If possible, blow dry air through the cylinder block.

To determine the clearance between the piston and the cylinder, measure the diameter of the pistons. In all types of engines this is done at the bottom of the piston skirt. Write down the obtained values. Next, the cylinder diameters are measured as described below. For this purpose, a bore gauge is used:

1. Measure the cylinder diameter at a height of 10 mm from the top edge and 10 mm from the bottom edge.

2. Additionally, measure the diameter at half the height of the cylinder.

3. The above measurements are taken in the direction of the longitudinal and transverse axes of the cylinder block. Thus, six measurements are performed for each cylinder. The difference between the upper and lower dimensions is the taper, the difference between the diameters in the longitudinal and transverse directions is the piston ovality. Any of the obtained diameters must not be less than that given in Specifications. There are several repair sizes of pistons available. The cylinder block can be bored accordingly. The mating surface of the cylinder block must be checked for flatness in the same way as the cylinder head. The surface is checked in longitudinal, transverse and diagonal directions. Maximum non-flatness - no more than 0.10 mm.