1. Disconnect the wire from the negative terminal of the battery.
2. Press the lock...
3. ...and disconnect the wiring harness connector from the electro-hydraulic valve of the exhaust camshaft.
4. Similarly, disconnect the wiring harness connector from the electro-hydraulic valve of the intake camshaft.
5. Remove the air filter housing (see "Removal and installation the air filter and air duct").
6. Remove the timing belt from the camshaft pulleys (see "Replacing the timing belt").
7. Remove the cylinder head cover (see "Replacing the cylinder head cover gasket").
8. Using a wrench to hold the exhaust camshaft from turning, unscrew the toothed pulley mounting bolt plug...
9. ...and remove the plug.
10. Similarly, unscrew and remove the plug of the intake camshaft.
11. While holding the exhaust camshaft from turning, remove the toothed pulley mounting bolt...
12. ...and remove the pulley.
13. Similarly, unscrew the bolt and remove the toothed pulley of the intake camshaft.
14. Replace the sealing gaskets of the camshaft toothed pulley bolt caps, regardless of their condition.
15. Place a jack or support under the engine crankcase.
16. Unscrew the bolt...
17. ...and unscrew the two nuts securing the right support of the power unit suspension to the body side member.
18. Remove the three bolts securing the support to the engine bracket...
19. ...and remove the support.
20. Remove the bolt securing the power steering pipe holder to the support bracket.
21. Remove the three bolts securing the bracket to the engine.
22. Remove the bracket.
23. Remove the three upper bolts...
24. ...and one lower bolt securing the upper timing gear housing.
25. Overcoming the resistance of the clamps, disconnect the wiring harness holder from the upper casing.
NOTE: This is how the wiring harness retainer retaining clips are located.
26. Remove the upper drive belt cover.
27. Remove the bolts securing the front camshaft bearing cover to the cylinder head...
28. ...and remove the lid.
29. Clean the mating surfaces of the cylinder head...
30. ...and the front cover of the camshaft bearings.
31. Remove the intake and exhaust camshaft oil seals from their seats in the cylinder head.
32. Replace the camshaft seals regardless of their condition.
33. Loosen the exhaust camshaft bearing cap mounting bolts in the sequence shown in Figure 5.5.
34. Finally, unscrew the bolts, remove the camshaft bearing caps...
35. ...and remove the exhaust camshaft.
36. Similarly, in the sequence shown in Figure 5.5, unscrew the bolts securing the intake camshaft covers, remove the covers...
37. ...and then the intake camshaft.
WARNING: The camshaft bearing caps are machined together with the cylinder head beds, so they must not be depersonalized. The bearing ordinal numbers are stamped on the caps. The numbers, made in the casting, are technological for the cap casting process and do not serve as a guide for installing the caps. Install the camshaft bearing caps in strict accordance with the markings applied to them.
38. Inspect the camshafts. The bearing journal surfaces...
39. ...and the cams must be well polished and without damage. No scoring, nicks, scratches, or aluminum drag from the bearing seats in the cylinder head are allowed on the working surfaces of the journals. If signs of seizure, overheating, deep scratches, or faceted wear are found on the working surfaces of the cams, replace the shafts.
WARNING: Grinding the camshaft lobes to eliminate stepped wear is prohibited, since changing the cam profile dimensions will disrupt the valve timing.
40. In workshops equipped with special tools and devices, you can check the radial runout of the camshaft journals. If the runout is more than 0.02 mm or the journals are not aligned, replace the shaft, as its straightening is not allowed.
41. Lubricate the camshaft beds with clean engine oil and place the camshafts in them.
42. Install the camshaft bearing caps and tighten their mounting bolts evenly, moving from bolt to bolt through every other turn, in the sequence shown in Figure 5.6, to the torque specified in Appendix 1.
43. Press the exhaust and intake camshaft oil seals into the cylinder head sockets (see "Replacing camshaft seals").
44. Install the remaining removed parts in the reverse order of removal.
45. Adjust the valve clearances (see "Adjusting valve clearances").
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