Cylinder Block
- Visually check the cylinder block for scores, rust and corrosion. Also check for cracks or any other defects. Correct or replace the block if defective.
- Measure cylinder bore with a cylinder gauge at three levels in directions of A and B shown in illustration.
Level 1 : No. 1 piston ring position with piston at TDC
Level 2 : Center of cylinder
Level 3 : Bottom of cylinder
- If cylinder bores show more the specified out-of-round or taper, or if the cylinder walls are badly scuffed or scored, the cylinder block should be re-bored and honed and fitted with oversize pistons and rings.
Standard value
Cylinder bore: 85.00-85.03 mm (3.3465-3.3476 in.)
Out-of-roundness and taper of cylinder bore:
Max. 0.01 mm (0.0004 in.)
- If cylinder top ridge is worn in stages, cut away with ridge reamer.
- Oversize piston is available in one size.
Piston service size and mark mm (in.): 0.25 (0.010) O.S: 0.25
- To rebore the cylinder to oversize, keep the specified clearance between the oversize piston and the bore, and make sure that all pistons used are of the same oversize. The standard measurement of the piston outside diameter is taken at a level 2 mm (0.08 in.) above the bottom of the piston skirt and across the thrust faces.
Piston-to-cylinder wall clearance: 0.02-0.04 mm (0.0008-0.0012 in.)
- Check for damage and cracks.
- Check top surface for flatness. If excessive flatness is evident, grind to minimum limit or replace.
Standard value
Flatness of gasket surface : Max. 0.05 mm (0.0020 in.)
Cylinder block (New) height : 284 mm (11.18 in.)
Service limit
Flatness of gasket surface : 0.1 mm (0.0039 in.)
Overall height : -0.2 mm (-0.0079 in.)
NOTE: The cylinder block gasket surface should be ground within -0.2 mm (-0.0079 in.) including the ground surface of cylinder head gasket surface.