CYLINDER BLOCK 2-21 INSPECTION CYLINDER BLOCK 1. Inspect the cylinder block for scratch, fur and rust visually, check for invisible crack or other deformation using a proper tool and repair or replace if necessary. 2. Measure flatness of the cylinder block upper surface using a straight edge and a thickness gauge. When measuring, the cylinder block upper surface should be flat without a fragment. L4GC031A 3. Measure the cylinder bore towards A and B directions at 3- point height using a cylinder gauge. If the cylinder bore is larger than standard and the cylinder wall is scratched or furred excessively, bore and hone the cylinder block and install a new oversize piston and ring. 4.
If the top ridge is partially worn, cut it with a ridge reamer. 5. There are 4 kinds of oversize piston. 6. Flatness 0.03mm or less Parallelism 0.15mm or less Cylinder I.D 82.00 ~ 82.03mm Cylinder I.D cylindricity 0.01mm Items Size 0.25 OS 0.25mm 0.50 OS 0.50mm 0.75 OS 0.75mm 1.00 OS 1.00mm To bore the cylinder bore to the oversize, maintain the clear- ance between oversize piston and bore and use the same size of pistons. When measuring the piston O.D, measure flatness of the skirt thrust surface at 47mm below from the piston top land. Clearance between piston and cylinder 0.02 ~ 0.04mm