Replace the belt if, upon inspection, you find:
- traces of oil on any surface of the belt;
- traces of wear on the toothed surface, cracks, cuts, folds and separation of the fabric from the rubber;
- cracks, folds, depressions or bulges on the outer surface of the belt;
- fraying or delamination on the end surfaces of the belt.
Warning: A belt with traces of motor oil on any of its surfaces must be replaced, as oil quickly destroys rubber. The reason for oil getting on the belt (usually this is a leak in the crankshaft and camshaft seals) must be eliminated immediately.
Note: Carry out work on an inspection pit, overpass or, if possible, on a lift.
1. Open the hood.
2. Remove the accessory drive belt (see "Checking the tension and replacing the auxiliary drive belt of the F18D engine").
3. Remove the right engine splash guard (see "Removal and installation engine mudguards").
4. Remove the right front wheel.
5. Unscrew the two bolts 2 (Fig. 5.31) and remove the upper front timing belt cover.
Fig. 5.31. Removing the upper front timing belt cover: 1 - Upper front cover of the timing drive; 2 - mounting bolts
6. Set the piston of the 1st cylinder to the TDC position of the compression stroke (see "Setting the piston of the first cylinder of the F18D engine to the TDC position of the compression stroke").
7. Fix the position of the camshaft pulleys with a special tool.
Helpful Hint: If you don't have a special tool to fix the position of the camshaft pulleys, you can use a W38 bolt with two washers and a nut.
8. Unscrew the mounting bolt and remove the crankshaft pulley.
9. Unscrew the three bolts 2 securing the lower front cover 1 (Fig. 5.32) of the timing belt and remove the cover.
Fig. 5.32. Removing the lower front timing belt cover: 1 - lower front cover of the timing mechanism; 2 - mounting bolts
10. Install a reliable support under the engine. Unscrew the five bolts and unscrew one nut securing the right engine support and remove the support (see Fig. "Replacing the powertrain suspension mounts").
11. Remove the middle front timing belt cover, overcoming the resistance of its clips.
12. Loosen the tension roller mounting bolt 2 (Fig. 5.33). Insert the Allen key into the hexagonal hole of the tension roller and, turning key 1 clockwise, loosen the belt tension.
Fig. 5.33. Loosening the timing belt tension: 1 - Allen key; 2 - tension roller
13. Remove the belt from the crankshaft toothed pulley, from the tension and intermediate rollers and the camshaft pulleys.
Warning: After removing the timing belt, do not rotate the camshaft or crankshaft, as the pistons may damage the valves.
14. To replace the tension roller, unscrew the bolt securing it to the cylinder block and remove the roller.
Note: If you are disassembling the timing drive only to replace the tension roller, you do not need to remove the drive belt.
15. Install the tension roller in the reverse order of removal.
16. Check that the timing marks on the crankshaft and camshaft match (see "Setting the piston of the first cylinder of the F18D engine to the TDC position of the compression stroke").
17. Place the belt on the crankshaft toothed pulley.
18. Turn the tension roller clockwise until it stops and install a new drive belt, sequentially placing the belt on the camshaft pulleys, tension roller and intermediate roller.
19. Turn the crankshaft three full revolutions and make sure that the belt is correctly positioned in the pulley grooves.
20. Check the alignment of the timing marks on the camshafts and crankshaft.
21. Install the parts in the reverse order of removal.