Remove/install cylinder head cover

AR01.20-P-5014CW

Remove/install cylinder head cover

08.08.2019

Engine

271 in model 172, 204, 207, 212

Modification notes

05.08.2019

AH05.20-P-1000-09SZ, added.

Operation step 10

Shown on engine 271.9

1

Vacuum line

3

Crankcase ventilation hose

5

Sealing rings

2

Cylinder head cover

4

Bolts

Y32

Air pump switchover valve

 

Remove/install

1

Detach engine cover upward from the cylinder head cover (2).

 Grasp with both hands and pry off. Check seal; replace if necessary.

 Installation: When positioning the engine cover, ensure that the seal is seated correctly on the filler neck. The seal should not be pressed down by the engine cover, but must lie against the engine cover .

2

Remove ignition coils.

AR15.12-P-2003CW

3.1

Remove heat shield from the expansion reservoir of the power steering.

Engine 271.9 in model 204
Engine 271.9 in model 212
with code 924 (Bivalent natural gas drive)

AR46.25-P-1000CW

3.2

Remove secondary air system piping from the valve unit and cylinder head.

Engine 271.8 in model 172, 204, 207, 212
If installed.

AR14.30-P-7150EVO

4

Remove bracket from the secondary air system piping.

Engine 271.8 in model 172, 204, 207, 212
If installed.

AR14.30-P-7150EVO

5

Remove engine wiring harness.

AR01.00-P-2410-02V

 Screw/bolt, ground line to front cover

*BA01.30-P-1001-01J

6.1

Detach crankcase ventilation hose (3) from the cylinder head cover (2).

Engine 271.9 in model 204
Engine 271.9 in model 212
with code 924 (Bivalent natural gas drive)

6.2

Remove crankcase ventilation system pipe from the cylinder head and cylinder head cover (2).

Engine 271.8 in model 172, 204, 207, 212
If installed.

7

Detach vacuum line (1) from air pump switchover valve (Y32).

8

Unclip air pump switchover valve (Y32) from bracket.

9

Remove oil dipstick tube from the cylinder head cover.

Engine 271.8 in model 172, 204, 207, 212

AR18.40-P-3510EVO

10

Unscrew screws (4) and remove cylinder head cover (2).

AR01.20-P-5014-03Q

General information on checking camshafts and bearing points of camshafts

AH05.20-P-1000-09SZ

 Engine 271.8
Press pipe crankcase ventilation system to one side.

 Installation: Install new seals (5) and ensure that they are seated correctly in the cylinder head cover (2).

 Installation: Observe cylinder head cover (2) tightening procedure.

 Screw/bolt, cylinder head cover to camshaft bearing housing

*BA01.20-P-1001-01H

 Ignition coil to cylinder head cover

*BA15.12-P-1002-01F

11

Install in the reverse order.

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

12

Perform engine test run and check engine in terms of leak tightness while engine is running.

 Crankcase ventilation, cylinder head cover, camshaft bearing housing

Number

Designation

Engine 271

BA01.20-P-1001-01H

Screw/bolt, cylinder head cover to camshaft bearing housing

Nm

9

 Cylinder head

Number

Designation

Engine 271

BA01.30-P-1001-01J

Screw/bolt, ground line to front cover

M6

Nm

8

 Distributor ignition (DI [EZL]) system

Number

Designation

Engine 271

BA15.12-P-1002-01F

Ignition coil to cylinder head cover

Nm

8