Before you begin: remove the alternator belt (see subsection 3.8.).
1. Remove the three bolts and the front camshaft drive cover.
2. Set the piston of the first cylinder to TDC. To do this, turn the crankshaft by the crankshaft pulley mounting bolt so that the mark on the camshaft pulley is opposite the mark (antenna) on the rear cover of the camshaft drive.
3. Loosen the crankshaft pulley mounting bolt, securing the shaft from turning with a screwdriver.
4. Remove the pulley from the crankshaft.
5. Loosen the tension roller mounting nut and turn the roller to relieve belt tension.
6. Remove the worn camshaft drive belt.
7. Install a new belt onto the crankshaft timing pulley...
8....then onto the camshaft pulley, pulling the drive belt so that it does not sag. Make sure that the marks on the pulley and the rear cover match.
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9. Place the belt on the water pump sprocket and tensioner pulley.
10. Install the crankshaft pulley and tighten its mounting bolt to a torque of 99-110 N·m (9.9-11.0 kgf·m).
11. Tighten the belt by turning the roller accordingly and tightening its fastening nut (see note).
12. When the belt tension is correct, you can turn it 90° with two fingers (force 15-20 N). Turn the crankshaft two revolutions and check the belt tension again. Repeat the adjustment if necessary.
Note: A special key is required to tighten the belt. If you do not have a key, insert two metal rods of the appropriate diameter into the holes in the roller. Fix a screwdriver between the rods and turn the roller, thereby tightening the belt. Then tighten the nut.
13. Install the front camshaft drive cover. Then install the alternator drive belt and adjust its tension (see subsection 3.8.).