Head unit: camshafts

4.3 -

1	Special screw

2	Vertical cap

Seal

Screw

Washer

6	Horizontal cap

Screw

8	Valve cover

O-ring

10	Vertical head

11	Horizontal head

Stud bolt

Nut

Key

16	Camshaft - vertical head

17	Intake duct

22	Horizontal head camshaft

23	Copper gasket

Screw

25	Intake valve cover

Circlip

Spacer

O-ring

29	Aluminium gasket

Ring nut

31	Sensor mount

Screw

Parts catalogue


1100	Head: timing
1100	Vertical head
1100	Horizontal head
1100	INTAKE MANIFOLDS
1100S	Head: timing
1100S	Vertical head
1100S	Horizontal head
1100S	INTAKE MANIFOLDS

Caution

Bold reference numbers in this section identify parts shown in this exploded view diagram. These parts do not appear in the figures near the text.

Removing the engine oil temperature sensor


Operations	Reference - See Section
Disconnect oil temperature sensor	P 1, Arrangement of wiring on frame

The engine oil temperature sensor (18) is placed on the intake valve cover (25) of the horizontal head (11).

Take the sensor (18) off its mount (31).

Unscrew the ring nut (30) from the cover (25).

Remove the circlip (26) from the ring nut and withdraw the sensor mount (31).

Refitting the engine oil temperature sensor

Check seal (29) and spacer (27). Replace as required.

Note

Change the O-rings (28) before refitting.

Installation is a reversal of the removal procedure.


Operations	Reference - See Section
Connect oil temperature sensor	P 1, Arrangement of wiring on frame

Disassembling the intake manifolds


Operations	Reference - See Section
Remove the throttle body	L 6, Removing the throttle body

Note

This operation can be carried out even if engine is on the frame. For precision purposes, the figures show the head removed from the engine.

Undo and remove the lock nuts (14) of the vertical and horizontal head intake manifolds from the stud bolts (13).

Remove the manifolds (17).

Unscrew the stud bolts (12) and (13) from the heads, if needed.

Refitting the intake manifolds

Smear some recommended threadlocker on stud bolts (12) and (13), install them to heads (10) and (11) and tighten to the specified torque (Sect . C 3, Engine torque settings).

Position the intake manifolds (17) and secure them with the nuts (14).

Tighten the nuts (14) to the specified torque (Sect. C 3, Engine torque settings).


Operations	Reference - See Section
Fit the throttle body	L 6, Refitting the throttle body

Removing the cam covers


Operations	Reference - See Section
Remove the timing belt rollers from the heads	N 4.2, Disassembling the timing system

Note

For clarity purposes, the figures show the head removed from the engine block.

Unscrew the retaining screws (32) and (1) and remove the cap (2) from the vertical head (10).

Repeat procedure for the horizontal head (11).

Note

Be careful not to displace the keys (15) in the camshafts (16) and (22) when removing the cam covers

Unscrew the retaining screws (21) of the cover (20) supporting camshaft (16).

Remove the camshaft cap (20) from the head; keep the O-rings (19).

Now camshaft does not turn over ball bearings but onto hydrodynamic bearings, thus limiting the number of moving parts and helping heat dissipation.

Removing the valve covers

Unscrew the retaining screws (7) and remove the valve covers (8) and (25) with the O-ring (9).

Refitting the valve covers

Change the O-ring (9) at each reassembly.

Position the valve covers (8) and (25) with the O-ring (9) to the head.

Tighten the screws (7) to the specified torque (Sect. C 3, Engine torque settings).

Camshafts disassembly


Operations	Reference - See Section
Remove the timing covers and the timing belts	N 4.2, Removing the timing side covers
Remove the timing belt rollers from the heads	N 4.2, Disassembling the timing system

Note

This operation is also possible with rocker arms fitted onto cylinder head. For your convenience, the pictures show a cylinder head with removed rocker arms.

Remove the cam covers as described above.

Remove the key (15) from the camshaft.

Note

Rotate the camshaft (16) until finding a position at which cams will not contact the rocker arms. This will avoid damage to the components during removal.

Extract the vertical head camshaft (16) from its seat.

Remove the seal (3) from the head.

Checking the camshafts

Check that the contact surfaces of the cams are free from scratches, grooves, steps and waving. Worn cams prevent correct timing and lead to loss of performance.

Insert the camshaft between two centres and check deviation using a dial gauge.

- Service limit:

0.1 mm.

Note

Actual deviation is half the gauge reading.

The camshaft is marked as follows:

O: horizontal

V: vertical

Checking the oil seals

Change oil seals at each engine overhaul.

Fit the new oil seals squarely into their grooves using suitable drifts.

Lubricate oil seal lip after installation. This operation requires the utmost care.

Refitting the camshaft

Renew the seal (3) at each reassembly. Fit seal into its seat on the right side of head (10) with the side without the spring positioned as shown in the figure.

Caution

If you have left the rocker arms in place in the head (Sect. N 4.4, Refitting the rocker arms), rotate the camshaft (16) until finding the position at which the cams will not contact the rocker arms.

Before installing the camshaft, check its marking (A): “V” means vertical, while “O” means horizontal.

Lubricate camshaft seats with graphitized oil to ensure lubrication during crankshaft running-in.

Insert the camshaft (16) from the left side of the head (10).

Check key (15) and keyway for wear and then fit it.


Operations	Reference - See Section
Refit the side covers	N 4.3, Refitting the cam covers
Refit the timing belt rollers to the heads	N 4.2, Reassembling the timing system
Refit the timing belts and timing belt covers	N 4.2, Refitting the timing side covers

Refitting the cam covers

Lubricate the new O-rings (19) with the recommended grease and fit onto the cap (20).

Position the cam cover (20) to the left side of head.

Secure the cam cover (20) using the screws (21).

Tighten the screws (21) to the specified torque (Sect. C 3, Engine torque settings).

Note

Pay attention to the key (15) in the camshaft (16).

Position the horizontal head cam cover (2) to the left side of head and insert the retaining screws (1).

Ensure that the special screw (1) is correctly positioned.

Tighten the screws (32) and (1) to the specified torque (Sect. C 3, Engine torque settings).

Repeat procedure for the other head.


Operations	Reference - See Section
Refit the timing belt rollers to the heads	N 4.2, Reassembling the timing system