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Leon Mk1

Cylinder head: Assembly overview (engine code BYT)
Cylinder head: Assembly overview (engine code BYT)
  Note
t  Renew the cylinder head bolts.
t  On assembling, replace self-locking nuts, bolts subject to goniometric tightening, as well as o-rings and gaskets.
t  The plastic protectors fitted to protect the open valves must only be removed immediately before fitting the cylinder head.
t  When replacing the cylinder head or cylinder head gasket, the old coolant must also be replaced.
   
1 - Cylinder head gasket
q   Replace
q   Note the fitting position: The component number faces towards the cylinder head
2 - Bolt.
q   Tightening sequence → Fig.
3 - Cylinder head
q   Removing and installing → Chapter.
q   Checking for distortion → Fig.
4 - Cylinder head bolt
q   Replace
q   Correct sequence when slackening → Fig.
q   Note correct sequence when tightening → Fig.
5 - O ring
q   Replace
q   Lubricate with engine oil
6 - Plug
7 - O ring
q   Replace
q   Lubricate with engine oil
8 - Cover with oil separator
q   Removing and installing → Chapter.
9 - Bolt.
q   Tightening sequence → Fig.
10 - Oil filler cap
q   With gasket
11 - Engine cover panel
q   Removing and installing → Chapter.
12 - Seal
q   Renew if damaged or leaking
13 - Valve body
14 - Bolt.
q   4.2 Nm.
15 - Bolt.
q   9 Nm.
16 - Vacuum pump
q   Removing and installing → Chapter.
17 - Seal
q   Replace
18 - Bolt.
q   9 Nm.
19 - Joint mouth
20 - O ring
q   Replace
q   Lubricate with coolant
21 - Bolt.
q   25 Nm.
22 - Transport plate
23 - Bolt.
q   9 Nm.
24 - Hall sender -G40-
25 - Separating plate
26 - Bolt.
q   25 Nm.
27 - Transport plate

   
Sequence for loosening the cylinder head
–  Unscrew bolts -arrows-.
–  Release the cylinder head bolts in the sequence -1 to 5-.
  A15-10437
Cylinder head tightening sequence
–  Tighten the cylinder head bolts in the sequence -1 to 5- as follows:
1.  Tighten with torque wrench initially to 40 Nm.
2.  Use fixed wrench to turn 90° further.
3.  Use fixed wrench to turn 90° further.
4.  Pre-tighten the bolts -arrows- to 8 Nm.
5.  Retighten the bolts 90° -arrows- with the rigid wrench.
  A15-10432
Tightening sequence for the oil spray settling tank
–  Tighten the screws to 11 Nm in the following sequence -1 ... 6-.
  A21-10192
Checking cylinder head for distortion
–  Use a straightedge ruler and feeler gauge to measure for deformation at several points.
t  Maximum permissible deformation: 0.05 mm.
  V15-0654

Chain drive > < Valve control