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

Note: The camshaft toothed belt must be renewed every time it is removed, even if it is apparently in good condition.

Removal

1. Raise and support the front of the vehicle. Remove the engine undertray and the wheel arch splash shields as a unit.

2. Disconnect the battery negative lead.

3. Unclip the throttle cable from the air cleaner-to-air mass meter trunking. Slacken the clips and remove the trunking.

4. Remove the air cleaner.

5. Remove the steering pump drivebelt (when applicable) and the alternator drivebelt.

6. Remove the three bolts and rubber bushes which secure the camshaft toothed belt cover. Remove the cover and its seal (see illustrations).

Removing a belt cover bolt . . .

. . . and the rubber bush

The belt cover seal

7. Working through the wheel arch, slacken the six screws with splined heads which secure the crankshaft pulley to the sprocket.

For better access, unbolt the oil cooler hose clip from the inner wing.

8. Turn the crankshaft until the timing mark on the pulley is in line with the pointer and the timing marks on the camshaft sprockets are in line with the notches on the backplate (see illustrations). (To turn the crankshaft by means of the central bolt, a Torx socket, size E20, will be needed. If this is not available, engage 4th or 5th gear and turn the crankshaft by turning a front wheel. It is easier to do this smoothly if the spark plugs are removed).

Pulley notch and pointer must be aligned . . .

. . . and sprocket marks align with backplate notches (arrowed)

9. Remove the six screws with splined heads and lift off the crankshaft pulley. The screw holes are offset so it will only fit one way.

10. Slacken the camshaft belt tensioner screw using a 6 mm Allen key (see illustration).

Move the tensioner to slacken the belt and slip the belt off the sprockets and rollers.

Slackening the camshaft belt tensioner screw

11. Do not turn the crankshaft or camshafts while the belt is removed, or piston/valve contact may occur.

Refitting

12. Commence refitting by checking that the pulley and sprocket timing marks are still correctly aligned. Temporarily refit the pulley and secure it with two screws to do this.

When satisfied, remove the pulley.

13. Fit the new belt over the sprockets and rollers, being careful not to kink it. Observe any arrows or other indication of running direction.

14. Refit the crankshaft pulley. Secure it with the six screws with splined heads, tightened to the specified torque (see illustration).

Tightening one of the crankshaft pulley screws

15. The belt tension must now be set. The makers specify the use of a special tool (KM-666); if this is available, proceed as follows (see illustration).

Special tool KM-666 for tensioning the camshaft toothed belt

16. Fit the special tool to the tensioner. Make sure the tensioner is free to move.

17. Make a mark on the exhaust camshaft sprocket, seven teeth anti-clockwise from the timing mark. Turn the crankshaft clockwise until the new mark is aligned with the notch on the belt backplate. In this position tighten the tensioner screw to the specified torque, then remove the special tool.

18. If the special tool is not available, belt tension must be set by hand. Move the tensioner using a square drive in the hole provided, nip up the screw and check the tension. As a guide, tension is correct when the belt cannot quite be twisted through 90º by hand in the middle of the run between the exhaust camshaft sprocket and the idler roller.

If a spring balance is available, correct tension is indicated when in the same place the belt is deflected 10 mm by a load of 9 kg (see illustration). When tension is correct, tighten the tensioner screw to the specified torque.

Checking the belt tension using a spring balance and ruler

19. It must be emphasised that the method of setting belt tension without the special tool is given as a guide only. The consequences of a belt slipping or breaking in service could be serious. The only way to be certain that tension is correct is to use the maker's tool, or to have a Vauxhall garage carry out the work.

20. Whichever tensioning method was used, now turn the crankshaft through two full turns clockwise and check that the pulley and sprocket timing marks come back into correct alignment. If they do not, remove the belt and start again.

21. The remainder of refitting is the reverse of the removal procedure.