Camshaft - removal, examination and refitting

Engine repair procedures - 1.6 and 1.8 litre 8 valve / Camshaft - removal, examination and refitting

Removal
1 To remove the camshaft with the engine in the vehicle, first carry out the following operations:
a) Remove the timing cover and valve cover, then disconnect the timing belt from the camshaft sprocket
b) If the camshaft oil seal is to be renewed then the camshaft timing sprocket must be removed
2 Remove the camshaft bearing caps (see illustrations), making a careful note of their fitted positions for reference when refitting .

The caps are numbered (see illustration) but mark the side nearest the front of the cylinder head. No. 1 cap is the one with a small oil seal on it.

10.2a Cylinder head and camshaft components - carburettor engine

10.2b Cylinder head and camshaft components - fuel injection engine

10.2c Camshaft bearing cap number (arrowed)

3 Remove cap nos. 5, 1 and 3 in that order.

Now undo the nuts holding 2 and 4 in a diagonal pattern. The camshaft will lift the caps up as the pressure of the valve springs is exerted. When they are free, lift the caps off along with the camshaft. The oil seal on the front end of the camshaft will come with it.

Depending on tappet type, proceed as follows:
Shim bucket tappets
4 The tappet buckets are now exposed and may be lifted out (see illustration). Take each one out in turn, prising the little disc out of the bucket by inserting a small screwdriver either side and lifting the disc away. On its reverse, each disc is engraved with a size (eg. 3.75).

This is its thickness number. Note the number and then clean the disc and refit it, number side down. There are eight of these and they must not be mixed up. On assembly, each disc must go back into the bore from whence it came. This problem exists also for the valves, so a container for each valve assembly and tappet is required. Label the containers 1 to 8, as follows:
Containers 1 and 2 will be No 1 cylinder exhaust and inlet respectively Containers 3 and 4 will be No 2 cylinder exhaust and inlet respectively Containers 5 and 6 will be No 3 cylinder inlet and exhaust respectively Containers 7 and 8 will be No 4 cylinder inlet and exhaust respectively

10.4 Tappet bucket and shim

5 Note the thickness of all tappet clearance discs from Nos. 1 to 8 for use during reassembly.

Hydraulic bucket tappets 6 Lift out the tappets one by one, ensuring that they are kept in their correct order and can be returned to their original bores.

7 Place them, cam contact surface down, on a clean sheet of paper as they are removed.

8 Inspect the tappets for wear (indicated by ridging on the clean surface), pitting and cracks.

9 Tappets cannot be repaired and if worn, must be renewed.

Examination
10 Refer to Section 27 in Part A of this Chapter whilst noting that on exchange engines or cylinder heads, the camshaft is supplied with bearing shells instead of running directly in the head and bearing caps.

Exchange units supplied by VW may have an undersized camshaft with corresponding bearing shells. Where this is the case, the camshaft will have a yellow paint spot on it and the journal diameter will be 25.75 mm. An unmarked camshaft supplied with bearing shells will be of standard size with a journal diameter of 26.00 mm.

Refitting
11 Refer to Section 12.