Servicing valve gear: repairing: VW (BAH, BLM)

VW
Polo
2003
Power unit
4 - Cyl. injection engine (2 valves, roller rocker fingers)
Edition
04.2012
Servicing valve gear: repairing
Note
Cylinder heads which have cracks between the valve seats or between valve seat inserts and the spark plug thread can be used further without reducing service life, provided the cracks do not exceed a maximum of 0.5 mm in width, or when no more than the first spark plug threads are cracked.
Before carrying out any assembly work, it is necessary to lubricate points of support and sliding surfaces.
Camshaft:
checking axial play
Chapter
.
removing and installing
Chapter
.
Checking radial clearance with Plastigage, wear limit: 0.1 mm
Runout: max. 0.05 mm
Identification
Fig.
,
Fig.
tighten to 6 Nm + continue tightening
1
/
4
turn (90°)
renew
Follow installation instructions and sequence when loosening and tightening
Chapter
.
Cylinder head cover
Reworking the sealing surface is not permitted
With integrated camshaft bearings
Remove remnants of old sealant
before fitting, lubricate with AMV 188 001 02
Fit upwards at right angles with the pins in the cylinder head gasket holes
dismantling and fitting
Chapter
.
O-ring:
Lightly oil sealing lip of oil seal
Renew
Chapter
,
Roller rocker finger
Check roller bearing
Oil contact surface
Use securing clip to clip onto support element when installing
Support element
Do not interchange
With hydraulic valve clearance compensation
Oil contact surface
25 Nm
Support/lifting eye
Part numbers: SJ 403 0103 390 F (pulley side) SJ 403 0103 390 G (flywheel side)
Cylinder head:
reworking the camshaft sealing surface is not permitted
Rework valve seat
Chapter
.
Rework the sealing surface on engine block side
Fig.
Valves
Do not rework, only grinding is permitted
Valve dimensions
Fig.
Valve guide
checking
Chapter
.
Valve stem seal
Renew
Chapter
,
Valve spring
Removing and installing: Cylinder head removed: with 2037 installed:
Chapter
, renewing valve stem seals
Valve spring plate
Valve cotters
Reworking cylinder head sealing surface on engine block side
Cylinder head reworking dimension: a = At least 135.6 mm
Camshaft, check axial clearance
Special tools and workshop equipment required
Universal dial gauge bracket
VW 387
Dial gauge
Camshaft, check axial clearance
Perform measurements with support elements and cylinder head cover removed.
Strogly press the central camshaft bearing with thumb
arrow
and check the axial clearance by moving the camshaft from side to side.
Wear limit: max. 0.15 mm
Camshaft identification
Identification between cam pairs, incoming and outgoing cams, cylinder 1
Cylinder 1
arrow
032 AD
Valve dimensions
Note
The valves can not be reworked. They can only be fitted.
Dim.
Inlet valve
Exhaust valve
∅ a
mm
34,5
28,0
∅ b
mm
5,98
5,96
c
mm
99,25
99,25
α
∠°
45
45