Note. Since this work requires a certain amount of experience, only the basic provisions necessary for the work of an experienced mechanic are described.
Removing
1. Remove the air filter (2), depending on the engine model, together with an actuator for the circulation damper.
2. Remove the engine top cover (7/11).
3. Remove the cylinder head cover, refer to the appropriate section.
4. Remove the air intake.
5. Models with AT: Disconnect the vacuum line from the electric vacuum pump. At the same time, squeeze both clamps of the lock and pull out the pipeline. Disconnect the outlet pipe from the vacuum line.
6. Remove the EGR pipe clamp from the holder. Remove the changeover valve from the holder. At the same time, disconnect the two vacuum lines from the valve. Then disconnect the holder from the inlet pipeline.
7. Models with AT: Remove the transmission oil gauge guide tube near the lug.
8. Remove a fuel distributive highway with injectors.
9. Turn away bolts of fastening and remove the inlet pipeline from a head of cylinders. Disconnect the recirculation valve vacuum hose. Take the intake pipe away from the cylinder head and secure it with the attached wires in the engine compartment.
10. Remove a vent pipe of removal of crankcase gases from a head of cylinders.
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11. Disconnect the engine ventilation hoses (1) under the flange connection of the intake manifold and cylinder head.
12. Remove the compressor drive V-belt, refer to the appropriate section.
13. Remove the compressor suction and discharge pipes.
14. Remove the compressor.
15. Raise and place the car on stands. Remove facing of an impellent compartment from below.
16. Drain the coolant, refer to Section Coolant replacement - general notes.
17. Disconnect the exhaust pipe from the exhaust manifold. Disconnect the pipe holder from the gearbox. Lower the exhaust system slightly and secure it with a wire or cable connector.
18. Remove the exhaust gas recirculation pipe from the cylinder block. Remove the recirculation pipe holders on the right and left behind the cylinder head.
19. Remove the heater coolant hose. To do this, press the bracket so that it locks into place. After that take out the pipeline of a cooling liquid.
20. Set the piston of the first cylinder to the position 20°after TDC. To do this, turn the crankshaft by the pulley in the direction of engine rotation so that the 20°mark on the pulley matches the mark on the timing case cover. In this position, the cams of the first cylinder of the intake camshaft and the exhaust camshaft should be at an angle upwards.
21. Remove the thermostat housing, refer to Section Removal and installation of the thermostat.
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22. Remove front cover (3). To do this, unscrew the 2 mounting bolts (1) on both sides of the front cover (3). The bolts have a thread diameter of 8 mm, in addition, there are guide bushings on the back of the cover. Remove the bolts (2) (thread diameter 6 mm) and remove the cover (3). Pay attention to the presence of a mating ring between the cover and the cylinder head. Clean mating surfaces.
23. Paint the camshaft gears with respect to the chain.
24. Remove the chain tensioner, refer to the appropriate section.
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25. Remove the top slide rail. To do this, pull out the guide pin by the thread (1) using impact tool (2) or any other suitable tool. To do this, ensure the sliding of the load device in relation to the stop.
26. Remove the exhaust camshaft gear. When unscrewing the bolts, hold the camshaft from turning by the hexagon.
27. Turn away bolts of fastening of a cover of the bearing of a camshaft of inlet valves. Loosen the bolts in several steps. Position the bolts so that they can be installed in their original positions.
28. Remove the intake camshaft drive chain from the sprocket.
29. Remove the intake camshaft.
30. Remove the left guide pin.
31. Turn away bolts of fastening and remove a cover of a casing of the mechanism gas distribution from a head of cylinders.
32. Loosen the cylinder head cover bolts on a cold engine in the reverse order to their fastening, then remove the bolts.
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33. Measure the length of the M12 cylinder head bolts. The length of the new bolts is L = 102 mm. After each tightening, the length of the bolts increases. With a length of 106 mm or more, the bolts must be replaced. In this case, it is recommended to use only new bolts.
34. With the help of an assistant, remove the cylinder head.
Installation
Installation is carried out in the reverse order of removal. In doing so, the following must be observed:
1. Clean the plane of contact between the cylinder head and cylinder block and check for cracks and burrs. Clean threaded holes.
2. Install a new seal in place.
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3. Install the cylinder head so that the guide bushings in the cylinder block fit into the holes in the cylinder head. At installation of a head of cylinders watch position of directing.
Attention! The cylinder head bolts must be tightened with great care. Before tightening it is necessary to check the accuracy of the torque wrench. An angle washer, such as HAZET 6690, can be used to facilitate tightening the bolts to a given angle. In order not to load the torque wrench with a large torque, an angle washer must be used together with a rigid wrench.
Note. If an angle washer is not available, evaluate the wrench angle. To do this, position the hard key so that the handle of the key is along the side of the engine, and turn the key at a time so that the handle is perpendicular to the engine.
Technical data of a head of cylinders are resulted in Specifications.
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4. Lubricate the thread and bearing surface of the heads of the cylinder head bolts with oil and tighten in the prescribed sequence from 1 to 10, first until it touches the cylinder head, and then to the torques specified in the Specifications:
5. Lightly oil the bearing surfaces of the heads of the new mounting bolts (A) cylinder heads to the timing case cover and screw in the bolts. Tighten the bolts to the specified torque.
6. Lubricate with sealant «Omnifit FD 3041» before installing the guide pin. Fix the guide from above with a torque of 10Nm.
7. Install the intake camshaft. Lubricate the compensating elements and bearing mounting points. Lay the shaft so that the cams of the first cylinder are at an angle upwards.
Note. During long-term operation of the engine, check the axial play of the camshaft in the mounting bearing. Check the play of the camshafts, adjust if necessary.
8. Install the intake camshaft in its original place and evenly tighten the mounting bolts (risk of damage to the shaft). The camshaft bearings are numbered 1 to 10 starting at the intake camshaft side. Fasten the bearing cover in several steps in one turn increments, finally tighten to 21 Nm.
9. Tighten the exhaust camshaft gear bolts with new bolts to 20Nm. Then tighten the bolts by 60°.
10. Lubricate the mating surfaces of the front cover (3) on the cylinder head with sealant, e.g «Omnifit FD 3041».
11. Insert guide bushings for two bolts from behind the cover (1) (thread diameter 8 mm). Install a new coolant o-ring and replace the cap.
12. Tighten the bolts (1) on both sides with a torque of 25 Nm, bolts (2) (thread diameter 6 mm) moment 10 Nm.
13. Before installation, check for damage to the heater coolant hose, replace the hoses if necessary. Replace the O-ring on the coolant inlet.
14. Fix a pipe of system recirculation of the fulfilled gases with new sealing rings on the block of cylinders.
15. Fasten the exhaust pipe to the exhaust manifold with new bolts to a torque of 20Nm.
Attention! Replace the rivet nuts in the manifold. To do this, screw the auxiliary bolt into the rivet nut by hand and tap the bolt head to knock out the rivet nut. Insert new rivet nut with caulking bolt and tighten to 30Nm.
16. Fasten the downpipe holder to the gearbox with a torque of 20Nm.
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17. Fix the inlet pipeline (2) with new seals (1) on the cylinder head with a torque of 20 Nm.
Attention! Clean mating surfaces first.
18. Reinstall the air intake, checking the o-ring. If necessary, replace the ring.