Cylinder Block
- 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.
- Measure the cylinder bore with a cylinder gauge at the three levels indicated in the directions of A and B as 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 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 re-bored and honed. New oversize pistons and rings should be installed.
Standard value
Cylinder bore : [2.4L] 84.00-84.04 mm
(3.3071-3.3087 in.)
[2.7L] 86.7 mm (3.41 in)
Out-of-roundness and taper of cylinder bore :
Max. 0.02 mm (0.0008 in.)
- If a ridge exists at the top of the cylinder, cut it away with a ridge reamer.
- Oversize pistons are available in two sizes.
Piston service size and mark mm (in.)
0.25 mm (0.010 in.) O.S. : 0.25 mm
0.50 mm (0.020 in.) O.S. : 0.50 mm
- 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 in.) 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 in.)
- Check for damage or cracks in the cylinders.
- 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 in.)
Service limit
Flatness of gasket surface : 0.05 mm (0.0002 in.)
CAUTION: When the cylinder head is assembled, grinding less than 0.2 mm (0.008 in.) is permissible.