Withdrawal
Connecting rod cap
Warning. To avoid errors during subsequent assembly, lay out the liners in accordance with their connecting rods (in order of cylinder numbering).
1. Turn away covers of a rod then remove a cover, and also the top and lower loose leaves.
2. Move the pistons with connecting rods to the top of the cylinders.
The procedure for removing and installing the piston pin
1. To separate and connect the piston and connecting rod, use a special tool (09234—33001).
2. Install the appropriate insert into the tool fork. Position the insert between the connecting rod and piston.
3. Insert the appropriate removable device into the hole in the fixture's bow.
Warning. Center the piston, connecting rod and piston pin on the mandrel of the puller.
4. Press the piston pin out of the top end of the connecting rod.
5. Install the correct guide pin into the piston and connecting rod. Insert the guide pin by hand into the piston bore. Push out the piston pin from the other side of the piston.
Warning. The guide pin centers the connecting rod in the piston. When the piston, connecting rod, piston and guide pins are installed on the tool yoke, the guide pin centers the entire assembly. If a guide pin that is too small is used, the piston assembly will not center in the tool, which could damage the yoke or tool insert.
6. Install the piston assembly on the tool yoke. The tool will support the connecting rod on the piston pin. Make sure the piston assembly slides on the yoke until the guide pin contacts the insert.
7. Adjust the setting mandrel to the appropriate length by turning the numbered sleeve on the lettered shaft until the alphanumeric value specified in the application diagram is obtained. Turn the knurled nut to lock the numbered bushing onto the shaft.
8. Insert the installation mandrel into the hole in the fixture arc. Press the piston pin into the connecting rod head until the adjusting mandrel bushing touches the top of the fixture arc.
Warning. Do not apply a load of more than 2200 kgf when the mounting mandrel bush rests in the arc.
Examination
Pistons and piston pins
1. Check each piston for scuffs, nicks, wear and other defects. Replace defective pistons.
2. Check each piston ring for breakage, damage and excessive wear. Replace defective rings. When a piston is replaced, its rings are also replaced.
3. Check the fit of the piston pin in the piston boss holes. Replace defective pistons and piston pins. The piston pin should slide smoothly into the piston boss holes by hand at room temperature.
Piston rings
1. Check the side clearance of the piston rings. If the measured value exceeds the allowable value, insert a new ring into the piston groove and measure the backlash. If the clearance again exceeds the allowable value, replace the piston and piston rings. If in this case the gap does not exceed the permissible value, replace only the piston rings.
Lateral clearance of piston rings:
- No. 1 - 0.03-0.09 mm
- No. 2 - 0.02-0.06 mm
Limit value:
- No. 1 - 0.1 mm
- No. 2 - 0.1 mm
2. For measurement of a backlash in the lock of a piston ring enter a ring into the cylinder. Install the ring in a plane perpendicular to the cylinder mirror, slightly pressing on it with a piston. Measure the gap with a feeler gauge. If the clearance is out of tolerance, replace the piston ring.
Piston ring gap:
- Rated value:
- No. 1 - 0.30-0.45 mm
- No. 2 - 0.25-0.40 mm
- Oil scraper ring - 0.30-0.90 mm
- Limit value:
- No. 1, No. 2 - 0.8 mm
- Oil scraper ring - 1.0 mm
When replacing piston rings without reboring the cylinders, place the ring on the lower, less worn part of the cylinder to check the clearance.
When replacing rings, make sure they are the same size.
Repair size of piston rings and marking:
- 0.25 mm OS-25
- 0.50 mm OS-50
- 0.75 mm OS-75
- 1,00 O.S — 100
Note. The marking is applied on the upper side of the ring near the lock.
Connecting rods
1. When installing the connecting rod cap, make sure the cylinder numbers printed on the connecting rod and cap match. When installing a new connecting rod, make sure the bushing retaining cutouts are on one side.
2. Replace the connecting rod if there is damage to the pressure-receiving surfaces of the upper and lower heads, and if there is stepped wear or if the inner surface of the upper head bore is very rough.
Installation
1. Install spacer ring.
2. Install the top side ring. To install it, insert one end of it between the wall of the piston ring groove and the spacer rubber ring, press it to the bottom of the groove and, pressing with your finger, as shown in the figure, insert the ring into the groove.
Warning. When installing the side rings, do not use a piston ring expander.
3. Install the bottom side ring in the same way.
4. Apply engine oil on the surfaces
5. Using a piston ring expander, install the No. 2 piston ring.
6. Install piston ring No. 1.
7. Position the piston rings so that the gaps in the locks of adjacent piston rings are as far apart as possible. Make sure these gaps are not in a plane away from the piston pin and load bearing.
8. When installing the piston in the cylinder, press the rings into the grooves of the piston using a swage.
9. Establish loose leaves of radical bearings in the block of cylinders.
10. Establish the bottom loose leaves in covers of radical bearings.
Note. Inserts with lubrication holes are installed in the cylinder block.
11. Fit the thrust plates into the N9 3 main bearing cap with the oil grooves facing out.
12. Make sure that the mark marking the front of the piston and the mark marking the front of the connecting rod (identification mark), are directed towards the front of the engine.
13. At installation of a cover of the lower head of a rod be convinced that marks corresponding to number of the cylinder, on a rod and a cover coincide.
14. When installing the connecting rod cap, make sure that the bushing retaining cutouts are located on one side.
15. Tighten the connecting rod cap nuts.
- Tightening torques: Lower head cover nuts - 50-53 Nm.
16. Check the gaps of the liners, for which:
- 1) Remove oil and dirt from bearings and necks.
- 2) Cut a piece of plastic template to a length equal to the width of the liner and place it along the axis of the neck away from the oil holes.
- 3) Install the inserts and cover. Tighten them to the required torque. Do not rotate the crankshaft while performing this operation.
- 4) Remove the bearing cap and, using the scale printed on the template package, measure the thickness of the plastic template at its widest point.
Connecting rod cap:
- Ear gap:
- Nominal - 0.016-0.046 mm
- Limit - 0.1 mm
17. Check up a backlash of a rod.
- Side clearance - 0.10-0.25 mm
- Limit value - 0.4 mm