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

Removal

1. The camshaft can only be removed without disturbing the housing if special tool 603 850, or equivalent, is available to depress the cam followers whilst the camshaft is withdrawn.

2. Assuming that the special tool is not available, the camshaft housing must be removed. Since the cylinder head bolts will be removed, it would certainly be good practice to fit a new cylinder head gasket; however, if the cooling system is drained and the housing is removed gently, there is a good chance that the head gasket seal will not be broken. It is the reader's choice whether to undertake the extra work of renewing the head gasket as a precaution, or to risk the vexation of finding that the old gasket has 'blown' after reassembly.

3. With the camshaft housing removed, clamp the cylinder head with four head bolts and some spacers if the head is not to be disturbed (see illustration).

Cylinder head bolt, with washers and nuts for spacers, used to clamp head

4. Undo the camshaft sprocket bolt, using an open-ended spanner on the flats of the camshaft to stop the shaft turning. Remove the bolt, washer and sprocket.

5. At the other end of the housing, remove the two Allen screws which secure the thrust plate. Push the camshaft rearwards and extract the plate (see illustrations).

Removing the Allen screws which secure the camshaft thrust plate

Removing the camshaft thrust plate

6. Carefully withdraw the camshaft from the distributor end of the housing. Be careful not to damage the bearing surfaces in the housing (see illustration).

Removing the camshaft from the housing

7. Where necessary, undo the bolts which secure the belt cover backplate and remove the plate (see illustration).

Camshaft belt cover backplate (1.3 litre engine shown)

Refitting

8. Prise out the oil seal with a screwdriver.

Drive in a new seal until it is flush with the housing, using a piece of wood or a suitably sized socket (see illustrations).

Prising out the camshaft housing oil seal

Fitting a new camshaft housing oil seal

9. Liberally lubricate the camshaft bearings and the oil seal lip. (If special lubricant has been supplied with a new camshaft, use it; otherwise use clean engine oil, perhaps with a molybdenum disulphide additive.) Carefully insert the camshaft.

10. Refit the thrust plate and tighten its screws. Check the camshaft endfloat using a feeler blade (see illustration). If the endfloat exceeds that specified, renew the thrust plate.

Checking the camshaft endfloat

11. Refit the belt backplate (where necessary).

12. Refit the camshaft sprocket, engaging the peg on the shaft with the hole in the sprocket.

Tighten the sprocket bolt to the specified torque, holding the camshaft as before (see illustrations).

Fitting the camshaft sprocket. Peg locating hole is arrowed

Tightening the camshaft sprocket bolt

13. Refit the camshaft housing.

14. If a new camshaft has been fitted, it is most important to observe the following running-in schedule (unless otherwise specified by the manufacturer) immediately after start-up:

• One minute at 2000 rpm
• One minute at 1500 rpm
• One minute at 3000 rpm
• One minute at 2000 rpm

15. Change the engine oil (but not the filter, unless due in any case) approximately 1000 km after fitting a new camshaft.