Remove/install camshafts

AR05.20-D-6992NA

Remove/install camshafts

04.02.2019

Engine

612.981 in model 903.61/62/66/67, 904.61/62/66

with code ZU9 (National version for Mexico)

Engine

612.981 in model 903.61/66/67, 904.61/66

with code ZU7 (National version for Canada)

Engine

612.981 in model 903.61/66/67, 904.61/66

with code ZU8 (National version for USA)

Modification notes

20.03.2002

Cam shape of camshaft modified

Step 9

BT05.20-P-0002-01A

1

Intake camshaft

5

Chain tensioner

A

Locking bore

2

Exhaust camshaft

6

Front cover

B

Alignment bores

3

Retaining pin

7

Slide rail

4

Cylinder head cover

8

Driver

1

Intake camshaft

2

Exhaust camshaft

9

Bolts

10

Dowel pin

11

Camshaft sprocket

12

Bolts

13

Camshaft bearing cap



Remove

1

Remove cylinder head cover (4)

AR01.20-D-5014NA

2

Position piston of cylinder 1 to ignition TDC


Do not crank engine backwards or at intake camshaft (1) or exhaust camshaft (2),
as engine timing can otherwise be damaged.

 Crank engine clockwise at crankshaft to TDC marking (arrows).
Marking of intake camshaft (1) and exhaust camshaft (2) to camshaft bearing cap (13) (arrows) must be in alignment.

3

Lock intake camshaft (1)

 Insert retaining pin (3) at camshaft bearing cap 1 (13) into locking bore (A) in camshaft sprocket of intake camshaft (1).
Alignment bores (B) in camshaft sprockets of intake camshaft (1) and exhaust camshaft (2) are facing each other.

 Retaining pins

*111589031500

4

Remove front cover (6) at cylinder head

AR01.30-D-5700NA

5

Unscrew driver (8) at intake camshaft (1), remove slide rail (7)

Socket wrench socket 17 mm 6-point 3/8 inch square

6

Remove camshaft sprocket (11) at exhaust camshaft (2) and remove with mounted timing chain

 Counterhold exhaust camshaft (2) if necessary with open end wrench.

7

Remove camshaft bearing cap (13)

AR05.20-D-6992-04NA

Topical note

Marking on camshaft bearing caps

AH05.20-P-6992-04HE

8

Remove intake camshaft (1) and exhaust camshaft (2)



Install

9

Insert intake camshaft (1) and exhaust camshaft (2)



BT05.20-P-0002-01A


Oil hydraulic valve clearance compensating elements and camshaft bearing points, align intake camshaft (1) and exhaust camshaft (2) at axial bearing (arrows),
as intake camshaft (1) and/or exhaust camshaft (2) can otherwise be damaged.

 Mount intake camshaft (1) and exhaust camshaft (2) so that both alignment bores (B) in camshaft sprockets face each other and the markings of intake camshaft (1) and exhaust camshaft (2) and camshaft bearing cap (13) are in alignment (arrows).
Intake camshaft (1) and exhaust camshaft (2) are very fragile. Ensure they are installed free of tension.

Camshaft code numbers

*BE05.20-N-1001-01C

10

Mount camshaft bearing cap (13)

AR05.20-D-6992-04NA

Topical note

Marking on camshaft bearing caps

AH05.20-P-6992-04HE

 Install camshaft bearing cap (13) in reverse order at same location. Tighten bolts (12) evenly in increments of, in each case,
1 revolution.

 Screw/bolt, camshaft bearing cap to cylinder head

*BA05.20-P-1001-01F

11

Install camshaft sprocket (11) with mounted timing chain and new bolts (9) on exhaust camshaft (2)

 Take into account dowel pin (10). Counterhold exhaust camshaft (2) if necessary with open end wrench.

 Bolt, camshaft sprocket to exhaust camshaft

*BA05.10-P-1003-01A

12

Install chain tensioner (5)

AR05.10-D-7800NA

13

Check basic position of camshafts

AR05.20-D-6010NA

Where necessary after check



Correct basic position of camshafts.

AR05.20-D-6025NA

14

Insert slide rail (7), screw driver (8) into intake camshaft (1)

Socket wrench socket 17 mm 6-point 3/8 inch square

 Bolt, driver to intake camshaft

*BA05.20-P-1002-01F

15

Install front cover (6) at cylinder head

AR01.30-D-5700NA

16

Install cylinder head cover (4)

AR01.20-D-5014NA

Camshaft code numbers

Number

Designation

Engine 612.981

BE05.20-N-1001-01C

Camshaft code numbers

Intake

01

Exhaust

00

 Timing chain, chain tensioner

Number

Designation

Engine 612.981/990

BA05.10-P-1003-01A

Bolt, camshaft sprocket to exhaust camshaft

Nm

18

 Camshaft

Number

Designation

Engine 611.960/961/962/980/981/983/987, 612.961/962/963/965/966/967/981/990, 613.960/961

BA05.20-P-1001-01F

Screw/bolt, camshaft bearing cap to cylinder head

Nm

9

 Camshaft

Number

Designation

Engine 611.960/961/962/980/981/983/987, 612.961/962/963/965/966/967/981/990, 613.960/961

BA05.20-P-1002-01F

Bolt, driver to intake camshaft

Nm

50