Cylinder Block
Disassembly
Remove the timing belt, cylinder head assembly, drive plate, transaxle mounting plate, oil pan and oil pump case.
Inspection
Cylinder Block
1. Check the cylinder block for scores, rust and corrosion. Also check for cracks or any other defects. Replace the block if defective.
2. Measure the cylinder bore with a cylinder gauge at the three levels indicated, in the directions A and B.
Level 1 No.1 piston ring position 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: 86.7 mm (3.41 inch)
Out-of-round and taper of cylinder bore Max. 0.02 mm (0.0008 inch)
4. If a ridge exists at the top of the cylinder, cut it off with a ridge reamer.
5. Oversize pistons are available in two sizes.
Piston service size and mark mm (in.)
0.25 mm (0.010 inch) O.S: 0.25
0.50 mm (0.020 inch) O.S: 0.50
6. To rebore the cylinder bore to the oversize, maintain the specified clearance between the oversize piston and the bore and make sure that all used pistons are the same oversize.
The standard measurement of the piston outside diameter is taken at a level of 15.5 mm (0.61 inch) above the bottom of the piston skirt and across the thrust faces.
Piston -to-cylinder clearance 0.01 - 0.03 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 the limit, 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 (0.0020 inch)
Caution: When the cylinder head is assembled, grinding less than 0.2 mm (0.008 inch) is permissible.
Boring Cylinder
1. Oversize pistons should be selected according to the largest bore cylinder.
Note: The size of piston is stamped on top of the piston.
2. Measure the outside diameter of the piston to be used.
3. According to the measured O.D., calculate the new bore size.
New bore size =
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.
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
Install the following parts by referring to their respective procedures.
1. Crankshaft
2. Drive plate
3. Piston
4. Cylinder head
5. Timing belt
6. Oil pump case