Withdrawal
Remove the cylinder head, belt drive wheels, front cover, flywheel, pistons and crankshaft (refer to the relevant sections).
Examination
Cylinder block
1. Visually check the cylinder block for scratches and rust. Also check for cracks and other defects. Correct or replace the defective unit.
2. Using an inside gauge, measure the diameter of the cylinders at three levels in directions A and B.
- Level 1: The location of the No. 1 piston ring when the piston is at top dead center.
- Level 2: in the center of the cylinder.
- Level 3: at the bottom of the cylinder
3. If the cylinders have excessive roundness or taper, and the cylinder walls are severely worn or scored, the cylinder block should be rebored and honed, after which oversized pistons and piston rings should be installed.
Rated values:
- Cylinder - 85.00-85.03 mm
- Out-of-roundness and taper of the cylinder - maximum 0.01 mm
4. If the top of the cylinder is worn with steps, cut them off with a reamer.
5. Oversized pistons are available in four sizes.
Piston size and marking:
- 0.25 O. S - more than 0.25 mm
- 0.50 O. S - 0.50
- 0.75 O. S - 0.75
- 1.00 O. S - 1.00
6. When boring oversized cylinders, allow some clearance between the oversized piston and the cylinder and ensure that all pistons used are the same size. The standard measurement of the outer diameter of the piston is taken at a distance of 2 mm from the edge of the piston skirt on the pressure-receiving surfaces.
- The gap between the piston and the cylinder wall is 0.01-0.03 mm
7. Check for damage and cracks.
8. Check the flatness of the top surface. If there is excessive deflection, grind the block or replace.
Rated values:
- Non-flatness of the upper surface of the block maximum - 0.05 mm
- Overall height - 284 mm
Limit values:
- Non-flatness of the upper surface - block 0.1 mm
- Overall height - 0.2 mm
Note. The top surface of the cylinder block should be ground to -0.2 mm, as well as the bottom surface of the cylinder head.
Cylinder boring
1. The oversized pistons used must be determined based on the largest cylinder size.
Identification label | Size |
0.25mm O.S | more by 0.25 mm |
0.50mm O.S | 0,50 |
0.75mm O.S | 0,75 |
1.00mm O.S | 1.00 |
O. S - oversized
Note. The dimension mark is applied to the piston head.
2. Measure the outside diameter of the piston to be used.
3. Based on the results of measuring the outer diameter of the piston, calculate the diameter of the cylinder after processing. Cylinder diameter after boring - piston outer diameter + (0,02—0,04) mm (clearance between piston and cylinder bore) - 0.02 mm (allowable honing limit).
4. Rebore each cylinder to the calculated size.
Note. To prevent deformation of the cylinder block due to temperature increase during honing, bore the cylinders in the following order (cylinder number): 2-4-1-3.
5. After honing the cylinders, bring them to the required size (piston outer diameter + clearance between piston and cylinder bore).
6. Check up size of a backlash between the piston and a cylinder mirror.
Note. When boring cylinders, bring all four cylinders to the same size. Do not bore only one cylinder to a larger diameter.
Installation
1. Install the following parts using the instructions in the relevant sections:
- 1) Crankshaft.
- 2) Flywheel.
- 3) Pistons.
- 4) Cylinder head.
- 5) Timing belt gears.
- 6) Front cover.