Cylinder Block Assembly: Testing and Inspection

DISASSEMBLY
Remove the cylinder head, timing belt train, front case, flywheel, Piston and crankshaft.

INSPECTION
Cylinder Block
1. Visually check the engine block for scores, rust and corrosion. Also check for cracks or any other defects. Repair or replace the block if defective.





2. Measure cylinder bore with a cylinder gauge at three levels in directions of A and B.
- Level 1: No. 1 piston ring position with piston at TDC
- Level 2: Center of cylinder
- Level 3: Bottom of cylinder
3. If cylinder bores show more than specified out-of-round or taper, or if cylinder walls are badly scuffed or scored, rebore and hone engine block, and fit with new, oversize piston and rings.

Standard value:
Cylinder bore: 85.00 - 85.03 mm (3.3465 - 3.3476 inch)
Out-of-roundness and taper of cylinder bore:
Maximum: 0.01 mm (0.0004 inch)

4. If cylinder top ridge is worn in stages, cut away with ridge reamer.





Piston service size and mark mm (inch)

5. Oversize pistons are available in four sizes.
6. 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 inch) above the bottom of the piston skirt and across the thrust faces.

Standard value:
Piston-to-cylinder wall clearance: 0.01 - 0.03 mm (0.0004 - 0.0012 inch)






7. Check for damage and cracks.
8. Check top surface for flatness. If excessive flatness is evident, grind to minimum limit or replace.

Standard valve:
Flatness of cylinder block surface: Max. 0.05 mm (0.0020 inch)
Engine block (New) height: 284 mm (11.18 inch)
Limit:
Flatness of cylinder block surface: 0.1 mm (0.0039 inch)
Overall height: -0.2 mm (-0.0079 inch)

NOTE: The cylinder block surface should be ground to within -0.2 mm (-0.0079 inch) even with the grind of cylinder head surface.

Boring Cylinder
1. Oversize pistons used should be determined based on the largest bore cylinder.





NOTE: Size mark is stamped on top of the piston.





2. Measure the outside diameter of the piston to be used.
3. Based on the measured O.D., calculate the boring finish dimension.

Boring finish dimension = Piston O.D + 0.02 to 0.04 mm (0.0008 to 0.0016 inch) (clearance between piston and cylinder) - 0.02 mm (0.008 inch) (honing margin inch)

4. Bore each of the cylinders to the calculated size.

CAUTION: To prevent distortion that may result from temperature rise during honing, bore the cylinder holes in the firing order sequence.

5. Hone the cylinders, finishing them to the proper dimension (piston outside diameter + gap with cylinder).
6. Check the clearance between the piston and cylinder.

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