Remove/install cylinder head

AR01.30-L-5800VB

Remove/install cylinder head

2.3.10

 

Remove/Install

Danger!

Risk of injury to skin and eyes suffering scalding from contact with hot coolant spray. Risk of poisoning from swallowing coolant.

Do not open cooling system unless coolant temperature is below 90 °C. Open cap slowly and release the pressure. Do not pour coolant into beverage bottles.

Wear protective gloves, protective clothing and eye protection.

AS20.00-Z-0001-01A

1

Drain coolant at crankcase

AR20.00-L-1142VA



Notes on coolant

All engines

AH20.00-N-2080-01A

2

Remove cylinder head cover

AR01.20-L-5014VB

3

Remove ignition coil module

AR15.12-L-1100VB

4

Take off exhaust manifold with catalytic converter/ muffler (13) at cylinder head (1)



 Installation: Replace seal (12). Inspect condition of stud bolts in cylinder head, if necessary 

*BA14.10-P-1001-01C

Replace stud bolts

5

Remove air shutoff valve

 On engines fitted with air pump

AR14.30-P-7200GF

6

Remove coolant thermostat

AR20.10-L-2460VA

7

Position piston of cylinder 1 to ignition TDC

 The TDC marking on the belt pulley must be aligned with the positioning edge on the timing case cover (arrow). The cams at cylinder 1 are positioned up at an angle.

8

Mark camshaft sprocket (9) and timing chain (8) to each other

Installation: Ensure that the marking of the timing chain (8) is matched with the marking on the camshaft sprocket (9), if necessary 

Inspect basic position of camshaft,
if necessary after inspecting 

AR05.20-P-6010GF

Set basic position of camshaft

AR05.20-L-6020VB

9

Remove chain tensioner (3)

AR05.10-L-7800VB

10

Take off camshaft sprocket (9) at camshaft (2) and lift off timing chain (8)

Use open-end wrench (14) to counterhold the camshaft (2)

 Installation: Replace torx bolts (7), use only once. Pay attention to dowel pin (10).

*104589010100



*BA05.20-P-1001-01C

11

Take off engine mount (5) at engine support (4)


 Support engine from below.

*BA22.10-P-1005-01G

12

Unscrew torx bolts (16) in chain housing



*BA01.30-P-1002-01E

13

Slacken cylinder head bolts (15) in stages, remove

 Slacken cylinder head bolts (15) in the reverse order of the tightening diagram once engine has cooled down.

Tightening diagram of cylinder head bolts

AR01.30-P-5800-01GF

 Installation: Oil cylinder head bolts (15) at thread and bolt head contact surface, insert and tighten in stages.



*BA01.30-P-1001-01E

14

Inspect cylinder head bolts (15)

AR01.30-P-5800-03GF

*BE01.30-P-1001-04C

15

Raise cylinder head (1), remove

 Installation: Replace cylinder head gasket (17).

 When fitting on cylinder head (1), insert guide rail pins in cylinder head into the guide rail (arrows).

Pay attention to dowel sleeves (18) for locating the cylinder head (1)

16

Clean contact surfaces and threaded holes

Separating surfaces and tapped holes must be free of oil and water. Inspect for cracks and flatness.

17

Apply sealant (arrows) to the web between cylinder head and timing case cover

 The sealing compound Loctite 5970 must be processed within 10 minutes.

*BR00.45-Z-1013-01A



*112589002500

18

Install in the reverse order

Danger!

Risk of accident from vehicle starting off by itself when engine running. Risk of injury from bruises and burns if you place your hand into the engine when it is started or when it is running.

Secure vehicle to prevent it moving off.

Always wear appropriate work clothing when working on the vehicle.

AS00.00-Z-0005-01A

19

Run engine and inspect for leaks

20

Inspect cooling system for leaks

 Do not pressure-test cooling system until engine has reached operating temperature.

 The cylinder head gasket is not watertight until the engine has reached operating temperature and the gasket has swollen.

AR20.00-L-1010VA

Number

Designation

Engine 166.961/
991

BE01.30-P-1001-04C

Cylinder head bolt

Thread diameter

M

10

Length (L) when new

mm

183

max. length (L)

mm

186

Number

Designation

Engine 166.961/
991

BA01.30-P-1001-01E

Bolt of cylinder head to crankcase

1st stage

Nm

35

2nd stage

 °

90

Step 3

 °

90

BA01.30-P-1002-01E

Bolt of cylinder head to timing case cover

Nm

20

Number

Designation

Engine
166.961/
991

BA05.20-P-1001-01C

Bolt of camshaft sprocket to camshaft

1st stage

Nm

20

Step 2



60

Number

Designation

Engine 166.961/
991

BA14.10-P-1001-01C

Collar nut of exhaust manifold with catalytic converter to cylinder head

Nm

30

Number

Designation

Engine 166.961/
991

BA22.10-P-1005-01G

Bolt of engine carrier to engine mount

Nm

55

Number

Designation

Order number

BR00.45-Z-1013-01A

Loctite sealant 5970

A 003 989 98 20