Note: A new camshaft oil seal and new rocker arm securing nuts should be used when refitting.

1.8 litre (R2A type)
Removal
1 Remove the cylinder head.

2 Unscrew the securing bolts and remove the rocker arm guides, rocker arms, and cam follower guide retainers, then lift out the cam follower guides and the cam followers. Keep all components in the correct order so that each component can be refitted in the original position if it is to be re-used. It is advisable to store the cam followers upright in an oil bath until they are to be refitted. Ensure that the depth of oil is sufficient to fully cover the cam followers.

3 Prise out the camshaft oil seal, taking care not to damage the surface of the camshaft. If necessary use self-tapping screws and a suitable pair of grips to withdraw the seal.

4 Unscrew the two securing bolts and withdraw the camshaft thrustplate from the front of the cylinder head.

5 Carefully withdraw the camshaft from the front of the cylinder head, taking care not to damage the bearings. If necessary, loosely refit the camshaft sprocket and bolt to aid removal.

Inspection
6 Examine the surfaces of the camshaft journals and lobes, and the cam follower rollers for wear. If wear is excessive, considerable noise would have been noticed from the top of the engine when running, and a new camshaft and followers must be fitted. It is unlikely that this level of wear will occur unless a considerable mileage has been covered. Note that the cam followers cannot be dismantled for renewal of individual components.

7 Check the camshaft bearings in the cylinder head for wear. If excessive wear is evident, it may be possible to have the head machined by a suitably equipped engineering workshop to enable a camshaft with oversize bearing journals to be fitted. The only other course of action available is renewal of the cylinder head.

8 Check the cam follower bores in the cylinder head for wear. If excessive wear is evident, the cylinder head must be renewed.

9 Check the cam follower oil ports and the oil holes in the cylinder head for obstructions (see illustrations).

23.9a Hydraulic cam follower oil port (arrowed) - 1.8 litre (R2A)

23.9b Cam follower supply hole (arrowed) in cylinder head - 1.8 litre (R2A)

Refitting
10 Commence refitting by lubricating the camshaft, bearings and thrustplate with hypoid oil, then carefully insert the camshaft from the front of the cylinder head, taking care not to damage the bearings (see illustration).

23.10 Refitting the camshaft - 1.8 litre (R2A)

11 Locate the thrustplate in the camshaft groove, then refit the bolts and tighten them.

Note that the stamped number on the thrustplate should face forwards (see illustrations).

23.11a Refit the camshaft thrustplate . . .

23.11b . . . and tighten the securing bolts - 1.8 litre (R2A)

12 Using a dial test indicator if available, or feeler blades, check that the camshaft endfloat is within the limits given in the Specifications. If not, renew the thrustplate and re-check. If this does not bring the endfloat within limits, the camshaft must be renewed.

13 Remove the thrustplate bolts, coat the threads with sealing compound, then refit and tighten the bolts.

14 Smear the lip of the new camshaft oil seal with clean engine oil, then fit the seal using the camshaft sprocket bolt and a suitable tool similar to that shown (see illustration).Draw the seal into position so that it rests on the shoulder.

23.14 Using a special tool to fit the camshaft oil seal - 1.8 litre (R2A)

15 Lubricate the cam followers with hypoid oil, refit them to their original locations, with the colour marking pointing to the oil feed hole in the cylinder head. The oil feed port in the cam follower should be opposite the oil feed hole in the cylinder head (see illustrations).

23.15a Hydraulic cam follower and rocker assembly orientation - 1.8 litre (R2A)

1 Cam follower colour markings 2 Oil port in cam follower 3 Oil supply hole in cylinder head 4 Securing bolt
5 Rocker arm guide
6 Rocker arm
7 Cam follower guide retainer - stepped end to inlet side 8 Cam follower guide - stepped end to exhaust side 9 Cam follower
10 Front of engine

23.15b Refit the cam followers . . .

16 Lubricate the tops of the cam followers, then refit the four cam follower guides to their original locations with their “stepped” ends pointing towards the exhaust side of the cylinder head (see illustration).

23.16 . . . guides . . .

17 Refit the four cam follower guide retainers to their original locations with their “stepped” ends pointing towards the inlet side of the cylinder head (see illustration).

23.17 . . . and retainers - 1.8 litre (R2A)

18 Temporarily refit the camshaft sprocket, and turn the camshaft so that the TDC pointer on the sprocket is aligned with the dot on the cylinder head front face (ie the pointer is at the 12 o’clock position).

19 Refit rocker arms Nos 1, 2, 4 and 5 together with their rocker arm guides and securing bolts, to their original locations (see illustration).

23.19a Rocker arm numbering sequence - 1.8 litre (R2A)

Lubricate the contact faces of the rocker arms and guides and the valve stems with hypoid oil, and ensure that the guides seat correctly in their locations in the cylinder head (see illustration).

23.19b Lubricate the valve stem contact faces and refit the rocker arms and guides - 1.8 litre (R2A)

Tighten the
securing bolts to the specified torque.

20 Turn the camshaft through 180º so that the camshaft sprocket keyway is aligned with the dot on the cylinder head front face (ie the TDC pointer on the sprocket is at the 6 o’clock position) (see illustration).

23.20 Camshaft sprocket keyway aligned with dot on cylinder head - 1.8 litre (R2A)

21 Repeat the procedure given in paragraph 19 for rocker arms Nos 3, 6, 7 and 8.

22 Remove the camshaft sprocket and refit the cylinder head.

1.6 and 1.8 litre (R6A type) Removal
23 Remove the cylinder head.

24 Unscrew the securing nuts and remove the rocker arm guides, rocker arms, and spacer plates, then lift out the cam followers.

Keep all components in the correct order so that they can be refitted in their original locations on reassembly. It is advisable to store the cam followers upright in an oil bath until they are to be refitted. Ensure that the depth of oil is sufficient to fully cover the cam followers.

25 Prise out the camshaft oil seal, taking care not to damage the surface of the camshaft. If necessary, use self-tapping screws and a suitable pair of grips to withdraw the seal.

26 Unscrew the two securing bolts, and withdraw the camshaft thrustplate from the front of the cylinder head.

27 Carefully withdraw the camshaft from the front of the cylinder head, taking care not to damage the bearings. If necessary, loosely refit the camshaft sprocket and bolt to aid removal.

Inspection
28 Proceed as described in paragraphs 6 to 9 inclusive.

Refitting
29 Commence refitting by lubricating the camshaft, bearings and thrustplate with hypoid oil, then carefully insert the camshaft from the front of the cylinder head, taking care not to damage the bearings.

30 Locate the thrustplate in position in the cylinder head, then refit the bolts and tighten them. Note that the oil groove in the thrustplate must face the front of the engine.

31 Using a dial test indicator (if available) or feeler blades, check that the camshaft endfloat is within the limits given in the Specifications. If not, renew the thrustplate and re-check. If this does not bring the endfloat within limits, the camshaft must be renewed.

32 Smear the lip of the new camshaft oil seal with clean engine oil, then refit the seal using the camshaft sprocket bolt and a suitable tool. The tool can be improvised using a metal tube of suitable diameter and a large washer or metal disc. Draw the seal into position so that it rests on the shoulder.

33 Lubricate the cam followers with hypoid oil, then refit them to their original locations in the cylinder head.

34 Before each rocker arm is fitted and its (new) nut tightened, it is essential to ensure that the relevant cam follower is positioned at its lowest point (in contact with the cam base circle, not the tip of the cam lobe). Turn the camshaft (by means of the camshaft sprocket bolt if necessary) as necessary to achieve this.

35 Lubricate the tops of the cam followers, then refit the spacer plates, rocker arms and rocker arm guides to their original locations.

36 Secure the rocker arms using new nuts tightened to the specified torque, bearing in mind the point made in paragraph 34.

37 Refit the cylinder head.