Cylinder Block Assembly: Testing and Inspection

CHECKING FLATNESS
1. Visually check for scratches, rust, and corrosion. Also, use a flaw detecting agent for the check. If defects are evident, correct, or replace.
2. Using a straightedge and feeler gauge, check the block top surface for warpage. Make sure that the surface is free from gasket chips and other foreign matter.
Standard value is 0.05 mm (0.0020 inch).
Limit is 0.1 mm (0.004 inch).
3. If the distortion is excessive, correct within the allowable limit or replace.
Grinding limit is 0.2 mm (0.008 inch) (includes/combined with cylinder head grinding)
Cylinder block height (when new) is 283.9 - 284.1 mm (11.177 - 11.185 inch).
4. Check cylinder walls for scratches and seizure. If defects are evident, correct (bored to oversize) or replace.





5. Using cylinder gauge, measure the cylinder bore and cylindricity. If worn badly, correct cylinder to an oversize and replace piston and piston rings. Measure at the points shown in illustration.
Standard value:
Cylinder I.D. 85.00 - 85.03 mm (3.3465 - 3.3476 inch).
Cylindricity 0.01 mm (0.0004 inch).





CHECKING THE BORES
1. Oversize pistons to be used should be determined on the basis of the largest bore cylinder.
Piston size identification. The size mark is stamped on piston top.
Size and identification mark
0.50 O.S. 0.50
1.00 O.S. 1.00
2. Measure outside diameter of piston to be used. Measure it in thrust direction as shown.
3. Based on measured piston O.D. calculate boring finish dimension.
Boring finish dimension = Piston O.D. + (clearance between piston O.D. and cylinder) - 0.02 mm (.0008 in.) (honing margin)
4. Bore all cylinders to calculated boring finish dimension.

CAUTION: To prevent distortion that may result from temperature rise during honing, bore cylinders, working from No. 2 to No. 4 to No. 1 to No. 3.

5. Hone to final finish dimension (piston O.D. + clearance between piston O.D. and cylinder).
6. Check clearance between piston and cylinder. Clearance between piston and cylinder is 0.03 - 0.05 mm (0.0012 - 0.0020 inch).

NOTE: When boring cylinders, finish all of four cylinders to same oversize. Do not bore only one cylinder to an oversize.