B1DJ0DK1 - 406D9 DW10 ENGINE

OVERHAUL CYLINDER HEAD

1 - DISMANTLING

Remove :

• the bolt (1)
• the setting rod [1p]
• the camshaft pulley hub (2)

Gradually loosen the securing bolts in sequence .

Remove :

• the main bearing cap casting (3)
• the camshaft (4)
• the camshaft lip seal

Marking their position, remove :

• the roller cam followers (5)/hydraulic tappets (6) assemblies

Remove :

• the valves (7) (use tool [12])
• the spring retainers (8)
• the abutment washers (9)
• the springs (10)

Remove :

• the valve stem oil seals (11) using tool [13]

Remove :

• anti-return valve (12)
• clean the joint faces with an approved descaling product; do not use sharp or abrasive tools; the joint faces must not have any trace of knocks or scores

2 - CHECKING THE FLATNESS

Maximum permissible bow = 0.05 mm .

Check the condition :

• of the valve seats and guides
• of the valves
• of the valve springs and their cups
• of the camshaft
• of the camshaft bearings
• of the various tapped holes
• of the hydraulic tappets
• of the valve rockers

IMPERATIVE : for checking, rectification or replacement of these parts, refer to the data sections .

3 - CHECK OF THE LONGITUDINAL CLEARANCE

IMPERATIVE : position the camshaft (4) in the main bearing caps casting (3) .

Fit the assembly (3), (4) .

Finger tighten then progressively tighten the securing bolts in the order shown .

Tighten the bolts to 1 daN.m .

To carry out this check :

• the camshaft must not be subject to any force (absence of the cam roller followers (5)/hydraulic tappets (6) assemblies)
• the camshaft main bearing cap casting (3) must be tightened to the correct torque

fit the dial gauge [7] using tools [5] - [8] .

This end float should be between 0,07 and 0,38 mm .

If incorrect :

• replace any defective parts

Remove the assembly (3), (4) .

4 - CHECKING VALVE PROTRUSION

Fit : The valves (7) .

Clean the checking surfaces .

Check the protrusion of the valves in relation to the cylinder head surface (4 Checking points (C)) :

• calculate the average of the values measured
• (A) exhaust valve = 0.2 mm (maximum)
• (B) inlet valve = 0.2 mm (maximum)

These values are obtained by grinding the valve seats .

Lap in the valves (if necessary) .

5 - REASSEMBLY

Fit a new anti-return valve (12) in the pipe (13) .

WARNING : ensure that the direction of fitting of the anti-return valve is correct .

insert the new valve stem seals using the tool [18] .

Fit :

• the valves (7) (stems oiled)
• the abutment washers (9)
• the springs (10) using the tool [12]
• the spring retainers (8)

WARNING : avoid direct contact of the hands with the roller tracks; apply a light film of clean engine oil to the rollers; check that there are no points of resistance on the rollers .

Refitting the tappets :

• lubricate the tappet bodies
• the roller cam followers (5)/hydraulic tappets (6) assemblies
• check that the tappets rotate freely in the cylinder head

Deposit a line of sealing compound (E10) at (D) around the edge of the mating surfaces .

IMPERATIVE : position the camshaft (4) in the main bearing caps casting (3) .

Fit the assembly : (3), (4) .

Finger tighten then progressively tighten the securing bolts in the order shown .

Tighten the bolts to 1 daN.m .

Before fitting the camshaft seal, ensure that the bottom of the seat is free of sealing compound .

Apply grease to the space between the oil seal lips .

IMPERATIVE : the outer face of the lip seal must be free of all traces of oil .

fit a new lip seal using tool [1q] .

Fit :

• the camshaft hub (2)
• the bolt (1)

Set the camshaft hub (2), using the tool [1p] .

Tighten the bolt (1) to 4,3 da.Nm .