Table of contents: ADP and AHL (SOHC) engines ↓ AEB and AJL engines (DOHC Turbo) ↓
ADP and AHL (SOHC) engines
Removal
1. Remove the top engine cover.
2. Remove the clamp and disconnect the crankcase ventilation hose from the valve cover. Remove the sealing ring.
3. Unfasten and remove the upper timing belt cover as described in paragraph 4.
4. Unscrew the valve cover mounting nuts. Note the position of the inner timing belt guide and the small bracket. Remove the reinforcing strips.
5. Remove the cover and gasket.
6. Remove the oil separator from the cover.
Installation
7. Clean the mating surfaces and apply the required sealant to the upper edges of the semi-circular cutout in the cylinder head
9. At the front of the cylinder head, apply a suitable sealant to the two contact points of the camshaft bearing cover and the cylinder head.
10. Carefully place the gasket on the cylinder head, place the cover together with the reinforcing strips and small bracket. Tighten the nuts gradually and evenly to the prescribed torque.
11. Install the upper timing belt cover and secure it with the latches.
12. Connect the crankcase ventilation hose together with the new O-ring and secure with a clamp.
13. Install the top engine cover.
Engines ADR, AFY, APT and APW (DOHC)
Removal
14. Remove the top engine cover.
15. Turn off the ignition, disconnect the high-voltage wires from the spark plugs of the first and second cylinders. Disconnect the wire from the ignition coil installed on the valve cover.
16. Unscrew the nut and disconnect the ground wire from the ignition coil.
17. Unscrew the mounting nuts, remove the ignition coil together with the high-voltage wires. Remove the gasket.
18. Unfasten and remove the upper timing belt cover.
19. Having noted the position of the heat shield, unscrew the nuts and bolts from the valve cover. Remove the heat shield, remove the cover from the cylinder head. Remove the main gasket and the center gasket of the spark plugs (fig. 7.19, e-v).
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Installation
20. Clean the mating surfaces of the cover and cylinder head, install the oil deflector.
21. At the rear of the head, apply a suitable sealant to the two contact points of the hydraulic tensioner/camshaft adjuster with the cylinder head (Fig. 7.21). Likewise, at the front of the cylinder head, apply a sealant to the upper contact points of the double bearing cap with the cylinder head.

22. Carefully place the gaskets on the cylinder head. Install the oil deflector plate and install the valve cover with heat shield (Fig. 7.22). Gradually tighten the nuts and bolts to the specified torque.

23. Install the upper timing belt cover and secure with latches.
24. Install the ignition coil together with the new gasket, making sure that the high-tension wires are pushed onto the spark plugs as far as they will go. Tighten the mounting nuts to the specified torque.
25. Install the top engine cover.
AEB and AJL engines (DOHC Turbo)
Removal
26. Remove the top engine cover.
27. Loosen the clamp securing the crankcase ventilation hose to the ventilation tube in the front part of the engine. Unscrew the mounting bolts (located on the riveted cover and cylinder head) and disconnect the ventilation tube from the hose. Move the tube to the side.
28. Unfasten and remove the upper timing belt cover.
29. Disconnect the wiring from the ignition coils on top of the valve cover.
30. In the front part of the valve cover, unscrew the bolt and disconnect the ground wire.
31. Loosen the mounting bolts and remove the ignition coils from the riveted cover, simultaneously disconnecting them from the spark plugs. Remove the sealing rings and replace them if necessary.
32. Unscrew the nuts, remove the valve cover from the cylinder head. Remove the main gasket and the center gasket of the spark plugs.
Installation
33. Clean the mating surfaces of the cover and head, install the oil separator.
34. At the rear of the cylinder head, apply a suitable sealant to the two contact points of the hydraulic tensioner with the cylinder head. Similarly, at the front of the cylinder head, apply a sealant to the two contact points of the double camshaft bearing cap with the cylinder head.
35. Place both gaskets on the cylinder head, install the valve cover with heat shield. Tighten the nuts and bolts to the specified torque.
36. Install each ignition coil together with the sealing rings, making sure that they are correctly connected to the high-voltage wires. Tighten the mounting bolts to the specified torque.
37. Connect the wiring to the ignition coils.
38. Install the ground wire and tighten the bolt.
39. Install the upper timing belt cover.
40. Connect the crankcase ventilation tube to the hose, connect the tube to the valve cover and tighten the bolts.
41. Install the top engine cover.


