Get Cylinderhead,valvecontrolmechanism -> 2 Camshaft mechanism - repair Guide for Volkswagen Fox SUV Second Generation (2003-2021)

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

2

Camshaft mechanism - repair

Camshaft - check axial clearance ⇒ page 40 .

Valve seat - grind ⇒ page 40 .

Valve guides - check ⇒ page 42 .

Valve stem seal - replace ⇒ page 43 .

2.1

Camshaft mechanism - repair

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Note

Engine head cylinder with fractures between valves seats or be‐

tween valve seat and Spark plug - Q- thread can still be used

without reducing the useful life, provided that the fractures are 0.5

mm wide at most or are located on the first 4 turns of the Spark

plug -Q- thread only.

WARNING

Always replace self-locking nuts and screws subject to angular

torque

2. Camshaft mechanism - repair

37

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

1 - Cylinder head cover

❑ Sealing surface cannot

be ground.

❑ With integrated cam‐

shaft bearings.

❑ Remove residues from

old gasket.

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❑ Before installation, ap‐

ply a coat of Sealing put‐

ty for engines -AMV 188

001 02- .

❑ For installation, put it in

the vertical position,

from up to down, with

the adjusting pins into

engine cylinder head

holes.

2 - 6 Nm + 90°

❑ Replace after each re‐

moval.

❑ Tighten from inside out.

3 - Camshaft

❑ Check axial clearance

⇒ page 40 .

❑ Check radial clearance

with plastigage, wear

limit 0.1 mm.

❑ Runout: max. 0.05 mm.

4 - Roller rockers

❑ Check roller rockers for

mobility.

❑ Lubricate sliding sur‐

face.

❑ For installation, fit to the

support element with safety clip.

5 - Support element

❑ Do not change positions.

❑ With valve clearance hydraulic offsetting.

6 - Keys

7 - Valve spring plate

8 - Valve spring

❑ With engine cylinder head removed, use the Compression device -2037- .

❑ With engine head installed ⇒ page 43 .

9 - Valve stem seal

❑ Replace ⇒ page 43 .

10 - Engine cylinder head

❑ Sealing surface on camshaft side cannot be ground.

❑ Grind valve seats ⇒ page 40 .

❑ Grind sealing surface on engine block side ⇒ page 39

11 - Valves

❑ Do not grind, may be seated only.

❑ Valve specifications ⇒ page 40

38

Rep. Gr.15 - Cylinder head, valve control mechanism

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

12 - 20 Nm + 90°

❑ Replace after each removal.

13 - Gear

❑ From Camshaft

❑ Immobilise the gear with the Special wrench -3036 - .

Grind sealing surface on the engine block side

Cylinder head grinding specification: -a- = at least 135.6 mm.

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2. Camshaft mechanism - repair

39

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

2.2

Camshaft - check axial clearance

Special tools and workshop equipment required

♦ Centesimal dial gauge

♦ Support -VW 387-

Camshaft, check axial clearance

Measure with support elements and camshaft cover removed.

– Press camshaft central bearing -arrow-, and check axial

clearance by moving the camshaft.

Wear limit: max. 0.20 mm.

Camshaft identification, distribution times

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Codes between intake and exhaust cams of cylinder 1 - BMD/

CHFB Engine

Cylinder 1

03DF

Distribution times for 1-mm valve clearance

BMD/CHFB engine

Intake valve

Exhaust valve

Then opens

Then closes

TDC

BDC

11° 48`

27° 26`

---------

--------

36° 28`

Opens be‐

fore

Closes be‐

fore

TDC

---------

1° 46`

Valve specifications

Note

Valves cannot be ground. They may be seated only.

Specification

Intake valve

34,5

Exhaust valve

Ø a

Ø b

c

mm

?°

28,0

5,96

99,25

45

5,98

99,25

45

a

2.3

Valve seat - trim

Special tools and workshop equipment required

40

Rep. Gr.15 - Cylinder head, valve control mechanism

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

♦ Depth vernier caliper

♦ Device for grinding valve seats

Note

♦ In case of repairs to engines with leaking valves, simply grind‐

ing or replacing the seats and valves is not enough. Especially

in engines with high kilometres traveled, the valve guides must

also be checked for wear. ⇒ page 42 .

♦ Grind valve seats until obtaining a perfect seating. Before

grinding, determine the maximum grinding elevation allowed.

If grinding elevation is exceeded, hydraulic offsetting of valve

clearance is no longer ensured and the engine cylinder head

must be replaced.

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Calculating maximum trimming specification allowed

– Install the valve and press it strongly against its seat.

Note

If the valve is replaced upon repair, use the new valve for meas‐

urement.

– Measure the distance -a- between valve end and engine head

upper surface.

– Calculate maximum and minimum grinding measurement of

the measured distance.

Minimum measurements: Intake valve = 7.6 mm and exhaust

valve = 7.6 mm.

Measured distance minus minimum distance = Maximum grinding

measurement allowed.

Example:

Measured distance

8,0 mm

7,6 mm

- minimum specification

Maximum allowable grinding specification

0,4 mm

The max. grinding measurement allowed is shown in the illustra‐

tions to grind the valve seats as per measurement “b”.

Grind intake valve seats

a

b

c

= Ø32,9 mm

= max. trimming specification allowed

= max. 1.8...2.0 mm

Z

a

ß

?

= Lower cylinder head edge

= 45° Valve seat angle

= 30° Upper correction angle

= 60° Lower correction angle

3) Calculating maximum grinding measurement allowed ⇒ page 40 .

2. Camshaft mechanism - repair

41

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

Grind exhaust valve seats

a

b

c

= Ø26.6 mm

= max. trimming specification allowed

= max. 1.8...2.0 mm

Z

a

ß

?

= Lower cylinder head edge

= 45° Valve seat angle

= 30° Upper correction angle

= 60° Lower correction angle

4) Calculating maximum grinding measurement allowed ⇒ page 40 .

2.4

Valve guides - check

Special tools and workshop equipment required

♦ Centesimal dial gauge

♦ Support -VW 387-

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Test sequence

– Place a new valve on the guide. Valve end shall be aligned

with guide. Due to the various valve guide diameters, we rec‐

ommend using only one intake valve on intake guide and one

exhaust valve on escape guide.

– Measure tilting clearence. Wear limit: 0.8 mm.

In case the clearance is exceeded:

– Replace engine cylinder head.

42

Rep. Gr.15 - Cylinder head, valve control mechanism

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

2.5

Valve stem seal - replace

Special tools and workshop

equipment required

♦ Support -VW 061- or Sup‐

port -10-222A-

♦ Support -10 - 222 A /1-

♦ Spark plug wrench -3122B-

♦ Valve spring compressor

-3362- with Pressure part

-3362/1-

♦ Seal fitter -3365-

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2. Camshaft mechanism - repair

43

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

♦ Wrench -3415-

♦ Pins -3415/1-

♦ Special wrench -3036-

♦ Flexible tube -VW 653/2A-

or Flexible tube -VW 653/3-

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2.5.1

Removal

(with engine head installed)

– Remove cylinder head cover ⇒ page 24 .

– Remove roller rockers and place them on a clean surface.

Make sure roller rockers are not touched.

– Remove the spark plugs with the Spark plug wrench -3122B- .

– Put the piston of the respective cylinder in “Bottom Dead Cen‐

tre”.

44

Rep. Gr.15 - Cylinder head, valve control mechanism

FOX 2004 ➤

3 - Cyl. injection engine - Edition 12.2009

– Install Valve spring compressor -3362- with the -3362/1- .

– Screw the Flexible tube -VW 653/2A- or Flexible tube -VW

653/3- to the spark plug thread.

– Connect pressure tube to compressed air with, at least, 6-bar

positive pressure and remove valve springs.

– Remove valve stem seals with the Impact extractor -3364- .

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2.5.2

Installation

– Install the supplied plastic bushing on the respective valve

stem. This way, damages to the valve steam seal are preven‐

ted.

– Install the new valve steam sealant in the Seal fitter -3365- .

– Lubricate the valve stem seal lip and carefully install on valve

guide.

– Install cylinder head cover ⇒ page 24 .

Resume the installation in the removal reverse order.

2. Camshaft mechanism - repair

45

Cylinderhead,valvecontrolmechanism -> 2 Camshaft mechanism - repair for Your Volkswagen Fox SUV Second Generation (2003-2021)

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