Cylinder Block

REMOVAL
Remove the timing belt, cylinder head assembly, drive plate, transaxle mounting plate, oil pan and the oil pump case.

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





2. Measure the cylinder bore with a cylinder gauge at the three levels indicated in the 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 the cylinder bores show more than the specified out-of-round or taper, or if the cylinder walls are badly scuffed or scored, the cylinder block should be rebored and honed. New oversize pistons and rings should be installed.
Standard value
Cylinder bore
[2.5 L] 84.00 - 84.04 mm (3.3071 - 3.3087 inch)
[2.7 L] 86.7 mm (3.41 inch)
Out-of-roundness and taper of cylinder bore
Max. 0.02 mm (0.0008 inch)
4. It a ridge exists at the top of the cylinder, cut it away with a ridge reamer.
5. Oversize pistons are available in four sizes.
Piston service size and mark
0.25 mm (0.010 inch) O.S: 0.25
0.50 mm (0.020 inch) O.S: 0.50
0.75 mm (0.030 inch) O.S: 0.75
1.00 mm (0.039 inch) O.S: 1.00
6. To rebore the cylinder to the 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 12 mm (0.47 inch) above the bottom of the piston skirt and across the thrust faces.
Piston -to-cylinder wall clearance 0.010 - 0.030 mm (0.0004 - 0.0012 inch)
7. Check for damage or cracks in the cylinders.





8. Check the top surface of the cylinder block for flatness. If the top surface exceeds limits, grind to the minimum limit or replace.
Standard value
Flatness of gasket surface Max. 0.03 mm (0.0012 inch)
Service limit
Flatness of gasket surface 0.05 mm (0.0002 inch)

CAUTION: When the cylinder head is assembled, grinding less than 0.2 mm (0.008 inch) is permissible.

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

Size: Identification mark
0.25 mm (0.010 inch) O.S: 0.25
0.50 mm (0.020 inch) O.S: 0.50
0.75 mm (0.030 inch) O.S: 0.75
1.00 mm (0.039 inch) O.S: 1.00

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

2. Measure the outside diameter of the piston to be used.





3. On the base of the measured O.D., calculate the boring finish dimension.
Boring finish dimension = Piston O.D + 0.01 to 0.03 mm (0.0004 to 0.0012 inch) (clearance between piston and cylinder) - 0.01 mm (0.0004 inch) (honing margin)
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.
Standard 0.01 - 0.03 mm (0.0004 - 0.0012 inch)

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

REASSEMBLY
1. Install the following parts by referring to their respective procedures.
1) Crankshaft
2) Drive plate
3) Piston
4) Cylinder head, refer to Cylinder Head Assembly; Service and Repair.
5) Timing belt, refer to Timing Components; Timing Belt; Service and Repair.
6) Oil pump case, refer to Engine Lubrication; Oil Pump, Engine; Service and Repair.