Four- and five-cylinder engines
1. Disconnect the wire terminal «masses» (-) from the battery.
2. Remove the air filter on vehicles with the Mopo-Motronic injection system.
3. Drain the coolant into a suitable container.
4. Disconnect the coolant circulation hoses from the cylinder head.
5. Remove a cover of the distributor of ignition together with wires of a high tension.
6. Disconnect cable «gas».
7. Five-cylinder engine. Disconnect the power steering pump and place it in the engine compartment. Do not disconnect hydraulic hoses from the pump.
Attention! The hoses are kink sensitive.
8. Designate accordingly all wires going to a head of the block of cylinders, and also to atomizers and an inlet manifold.
9. Disconnect the fuel injection pipes.
10. Label the vacuum hoses on the intake manifold or on the throttle valve fitting and disconnect them.
11. Disconnect the brake booster vacuum hose.
12. Remove the top part of an inlet collector at five-cylinder engines. Also remove the valve injectors, but do not disconnect the fuel lines from them yet.
13. Place injectors in clean, gasoline-resistant plastic bags.
14. Disconnect the cold start accelerator plug. Unscrew the valve and lay it aside from the place of work without disconnecting the fuel supply hose.
15. Designate plug connections of system of injection of fuel and disconnect them. The plugs are different colors.
16. Five-cylinder engine. Remove the fuel mixture adjuster together with the air filter housing.
17. Disconnect a reception pipe of mufflers from a final collector.
18. Four-cylinder engine. Disconnect the upper generator mounting bracket. Before doing this, loosen the tension of the V-belt.
19. Remove the toothed belt guard. Loosen the toothed belt tension and remove it from the camshaft drive gear.
20. Remove the cylinder head cover.
21. Turn out bolts of fastening of a head of the block of cylinders. The sequence of unscrewing the bolts is opposite to the tightening sequence (see illustration).
Attention! The cylinder head must be removed from a cold engine. Otherwise, the head removed from a hot engine may, after cooling, «story».
22. Remove the cylinder head together with the intake and exhaust manifolds fixed to it, as well as the ignition distributor (five-cylinder engine). If the head is difficult to separate from the cylinder block, loosen its fit by tapping with a plastic hammer.
Six-cylinder engine
The procedure for removing the cylinder head on this engine is given using the example of the left cylinder head. Removing the head from the right row is performed in the same way.
23. Remove the engine cover and ribbed belt guard.
24. Remove the ribbed belt, see the relevant chapter.
25. Remove a gear belt, the corresponding chapter see.
26. Disconnect a reception pipe of mufflers from a final collector.
27. Drain the coolant from the engine through the drain hole, as well as from the radiator through the hole at the bottom right.
28. Disconnect the sleeve of the air intake box (air intake) from the intake manifold.
29. Disconnect the plug from the Hall sensor.
30. Remove the crankcase ventilation hoses from the left and right sides of the cylinder head.
31. Disconnect the air supply hose from the air filter.
32. Disconnect the air conditioning and/or differential lock low pressure hose from the fitting on the left side of the throttle.
33. Remove the air intake from the engine compartment along with the crankcase ventilation hoses by pushing the air intake back and then lifting the entire assembly up.
34. Remove cable lock «gas», disconnect the cable and put it away from the work area.
35. Disconnect the plug of the intake air temperature sensor and the idle speed stabilization valve.
36. Disconnect the supply and discharge fuel hoses.
37. Disconnect the wire «masses» (-) from mounting behind the throttle valve.
38. Disconnect the hose from the control unit located in front of the throttle fitting.
39. Disconnect the throttle angle sensor plug.
40. Disconnect the canister solenoid valve hose from the throttle valve fitting on the right side.
41. Remove all spark plug tips
42. Disconnect all valve injector plugs
43. Disconnect the plug of the knock sensor and heating of the lambda probe.
44. Disconnect the lambda probe plug and set the wires aside.
45. Disconnect the engine oil pressure and temperature sensor plug (at the rear of the left cylinder head).
46. Disconnect the plug of the thermal switch of the fan blowing the radiator.
47. Disconnect the hose (of blue color) check valve, which is located in the same bundle with the vacuum brake booster hoses.
48. Disconnect the plugs on the injectors on the left and right sides.
49. Disconnect the hydraulic pipe mounting bracket mounted on the intake manifold. Do not disconnect the hydraulic drive.
50. Disconnect the intake manifold and remove it.
51. Seal the manifold openings with a clean rag.
52. Disconnect the coolant pipe from the rear end of the cylinder head.
53. Disconnect the gas analyzer tube.
54. Remove the lambda probe.
55. Remove the mounting bolts and remove the exhaust manifold heat shield.
56. Remove the cylinder head cover.
57. Remove the rear toothed belt guard.
58. Disconnect from the cylinder head the hose from the reservoir to the power steering pump.
59. Turn out bolts of fastening of a head of cylinders. The sequence of unscrewing the bolts is opposite to the order of their tightening (see illustration 8.21).
Attention! Remove the cylinder head from a cold engine. hot head after removal can «story».
60. Remove the cylinder head. If, due to a tight fit, the head does not detach, then tap it with a plastic hammer.
Examination
61. Remove the old gasket. The sealing surfaces of the cylinder head and block must be absolutely clean, free of sealant residues.
Attention! Do not clean the sealing surfaces of the cylinder head with sharp tools. The resulting scores or scratches can cause subsequent damage to the head.
62. Check up a head of the block of cylinders on absence of distortions. This is especially necessary if the gasket has burned through.
63. Place a long metal ruler or square along the cleaned sealing surface of the head and use a template to verify that there are no distortions greater than 0.1 mm. If the curvature is greater than the specified value, then the cylinder head should be ground.
Modification of the cylinder head is allowed within certain limits. The permissible minimum head height for four-cylinder engines is 132.6 mm, and for 5- and 6-cylinder engines 132.75 mm.
Installation
64. Lubricate the hydraulic tappet guides with a thin layer of grease if a new or replacement cylinder head is to be installed.
65. Lubricate the camshaft and install it in place (see relevant chapter).
Attention! The threads of the head bolts and the threads of the bolt holes in the cylinder block must be clean and undamaged. Otherwise, the tightening torque of the bolts will not correspond to the nominal. There must be no oil or liquid in the bolt holes. Failure to do so may result in rupture of the cylinder block metal.
66. Turn the crankshaft against the direction of rotation so that none of the pistons is at TDC. Otherwise, when the cylinder head is installed, the open valve may hit the piston.
67. Lay the cylinder head gasket on the cylinder block so that its marking or inscription «OBEN» (top) facing the head of the block.
68. Reinstall the cylinder head. For this purpose, workshops, when working with 4- and 5-cylinder engines, use two guide pins, which make it possible to avoid displacement of both the head itself and the gasket at the time of installation. Guide pins can be made independently by sawing off the heads of two old head bolts and sawing through the slot for a screwdriver. After screwing in several head mounting bolts, these guide pins are unscrewed with a screwdriver, and mounting bolts are screwed in their place.
69. Screw in all bolts of fastening of a head of the block of cylinders and tighten them in sequence as it is shown in an illustration 8.21. The tightening of the bolts is carried out in two or three steps, depending on the type of engine.
Four- and five-cylinder engines
1st stage. Screw in the bolts with a torque wrench with a torque of 40 Nm.
2nd stage. Tighten the bolts with a torque wrench to 60 Nm.
3rd stage. Tighten the bolts with a wrench half a turn, without interrupting the translational movement of the wrench. It is allowed to perform this operation with two additional turns of a quarter turn each. The sequence of tightening the bolts is the same as when they are screwed in and tightened.
Six-cylinder engines
1st stage. Screw in the bolts with a torque wrench with a torque of 60 Nm.
2nd stage. Tighten the bolts with a wrench by half a turn, without interrupting the translational movement of the wrench. It is allowed to perform this operation with two additional turns of a quarter turn each. The sequence of turning the bolts is the same as when they are screwed in and tightened.
After completing the turn, the tightening of the bolts is completed. Subsequent tightening is not allowed.
When installing the cable «gas» and valve injectors for a five-cylinder engine, pay special attention to their correct position.
Attention! Follow the tightening sequence for the intake manifold bolts on six-cylinder engines.
70. Check up a corner of an advancing of ignition after full installation of a head of the block of cylinders of four - and five-cylinder engines.
Attention! If the cylinder head was removed due to a damaged head gasket, the coolant must be completely drained and replaced with new. The same applies to replacing the cylinder head.
A defective cylinder head gasket can be recognized by one or more of the following:
- A) loss of coolant
- b) clouds of white gases from the exhaust pipe,
- V) when the engine is running, air bubbles come out of the expansion tank with coolant, and when the tank cap is opened, active coolant leaks in the form of foam,
- G) gray or brown emulsion on the engine oil dipstick due to coolant getting into the engine oil.
Attention! Coolant in the engine lubrication system can cause bearing failure. Replace the cylinder head gasket immediately. Don't start the engine! Delivery of the car to the workshop is carried out by loading onto the platform.
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