Opel Corsa B 1993–2000 Service and Repair Manual: Camshaft toothed belt - removal, refitting and adjustment

Note: The following procedure will necessitate re-positioning of the water pump which, in turn, is likely to cause leakage from around the sealing flange. Minor leakage can normally be rectified by using a proprietry radiator sealing product in the cooling system, although it is preferable to remove the water pump completely and fit a new sealing ring.

Removal

1. Undo the belt cover retaining bolts (early models) or release the retaining clips (later models) and remove the cover.

2. Use a socket or spanner on the crankshaft pulley to turn the crankshaft until No 1 piston is at its firing point, indicated by the notch on the crankshaft pulley being in line with the pointer on the oil pump housing, and the mark on the camshaft sprocket being in line with the rib on the camshaft housing (see illustrations).

Crankshaft pulley notch and oil pump pointer in alignment (arrowed)

Camshaft sprocket mark and housing rib (both arrowed) should be aligned

3. Slacken the alternator mounting and adjustment bolts, move the alternator towards the engine and remove its drivebelt. Where necessary, unscrew the union nuts and disconnect the oil cooler pipes from the filter housing to improve access to the crankshaft pulley.

4. On 1.3, 1.4 and 1.6 (16SV and C16NZ) litre engines, release the crankshaft pulley central bolt without disturbing the set position of the crankshaft. To prevent the crankshaft turning it may be sufficient to engage a gear (manual gearbox only) and apply the handbrake; a better way is to remove the flywheel bottom cover plate and jam the flywheel ring gear with a large screwdriver or a tyre lever (see illustration). Remove the bolt and the pulley.

Jamming the flywheel ring gear

5. On 1.6 (16SH), 1.8 and 2.0 litre engines, remove the four Allen screws which secure the pulley to the sprocket. Remove the pulley.

6. On all models, drain the cooling system.

7. On later (June 1990 onwards) 1.4 litre and 1.6 (16SV and C16NZ) litre engines which are fitted with a spring-loaded automatic tensioner, lock the tensioner in its slackest position. To do this move the tensioner indicator arm clockwise until the holes in the baseplate and arm align and lock the tensioner in position with a suitable rod.

8. On all models, slacken the three bolts which secure the water pump. The bolts are accessible through holes in the belt backplate (see illustration).

Slackening a water pump bolt

9. Swivel the pump to release the tension on the toothed belt. There are flats behind the pump sprocket for this purpose (see illustration). Note the belt's running direction if it is to be used again, then slip it off the sprockets. At this point, also note the statement at the beginning of this Section.

Swivelling the water pump using a spanner on the flats

10. A new belt, or one which is to be re-used, must not be kinked or be contaminated with oil, grease etc

Refitting

Later (June 1990 onwards) 1.4 litre and 1.6 (16SV and C16NZ) litre engines

11. Fit the new belt without disturbing the set position of the crankshaft and camshaft sprockets. Apply some tension by moving the water pump and check that the timing marks are correctly aligned (see illustration).

On 1.4 and 1.6 (16SV and C16NZ) litre engines, align the camshaft sprocket mark with the backplate rib and the crankshaft sprocket (1) is aligned with the backplate/oil pump housing groove (2)

12. Refit the crankshaft pulley bolt and withdraw the locking rod from the springloaded automatic tensioner.

13. Rotate the water pump and set the belt tension so that the automatic tensioner indicator arm and backplate holes are aligned (the tensioner arm will have moved fully clockwise). Tighten the water pump bolts securely.

14. Rotate the crankshaft smoothly through two complete turns clockwise until the timing marks are realigned.

15. Slacken the water pump bolts and rotate the pump anti-clockwise slightly until the automatic tensioner arm is positioned in the centre of backplate notch (see illustration).

When the tensioner is correctly positioned, tighten the water pump bolts to the specified torque setting.

Camshaft toothed belt tensioner indicator arm (1), baseplate (2) and locking holes - later 1.4 litre and 1.6 (16SV and C16NZ) litre engines

16. Rotate the crankshaft through two more complete turns clockwise (so that the timing marks are aligned again) and check that the tensioner arm and backplate notch are still correctly aligned. If not, repeat the operation in paragraph 15.

17. Once the tensioner position is correct, remove the crankshaft pulley bolt.

18. Refit all disturbed components by reversing the removal sequence. Adjust the auxiliary drivebelt and refill the cooling system.

All other models

19. Fit the new belt without disturbing the set position of the crankshaft and camshaft sprockets. Apply some tension by moving the water pump.

20. Refit the crankshaft pulley and check that the pulley and camshaft sprocket marks are still correctly aligned (paragraph 2). If not, release the belt tension and align the sprockets correctly. Tighten the crankshaft pulley bolt to the specified torque, using locking compound on the bolt threads.

21. To adjust the tension of the belt, ideally the tension gauge specified by the makers (KM-51 0-A) should be used (see illustration).

If this is available, proceed as follows.

Checking the camshaft toothed belt tension with gauge KM-510-A

22. Turn the crankshaft through at least half a turn in the normal direction of rotation. Set the tension gauge, apply it to the 'slack' side of the belt (above the alternator) and release it.

Read the gauge and compare the figure with that given in the Specifications.

23. If adjustment is necessary, move the water pump to increase or decrease belt tension, rotate the crankshaft through one full turn and take another gauge reading. Repeat as necessary until the desired tension is achieved.

24. In the absence of the belt tension gauge, an approximation to the correct tension can be judged by twisting the belt in the middle of its 'slack' side (between water pump and camshaft sprocket). It should just be possible to twist the belt through 9û º (a quarter turn) by hand (see illustration), A belt which is too tight will normally be heard to hum or honk when running,

Checking the belt tension by twisting it between the water pump and camshaft sprockets

25. When adjustment is correct, tighten the water pump bolts to the specified torque.

Refit and secure the belt cover.

26. Refit and tension the alternator drivebelt and refill the cooling system. Refit the flywheel bottom cover if it was removed.