Remove/install piston

AR03.10-S-7021B

Remove/install piston

5.8.11



Removing

1

Remove cylinder head

AR01.30-S-5800D

2

Remove oil pump

AR18.10-S-6020C

3

Remove connecting rod bearing cap (1)

 Mark connecting rod (2) in connecting rod bearing cap (1) to each other at the inlet side.

 Connecting rod (2) and connecting rod bearing cap (1) are cracked.

 External torx set

*001589760900

4

Mark connecting rod bearing shell and connecting rod bearing cap (1) to each other

 Do not mix up bottom connecting rod bearing shells.

5

Remove connecting rod (2) together with pistons (4) by lifting up and out

 If the direction of travel arrows (in opposite direction of power flow) on the pistons (4) are no longer recognizable, they must be re-marked.

6

Mark connecting rod bearing shell and connecting rod (2) to each other

 Do not mix up top connecting rod bearing shells.

7

Remove circlip (5) for piston pin (6)

 Do not damage piston (4). Use a clean cloth as a base.

8

Press out piston pin (6)

9

Check connecting rod (2)

 Inspect connecting rods (2) for blue discoloration, cross scores and notches.



Install

10

Assign piston (4) to cylinder bore

11

Oil piston pin (6) and connecting rod bush

12

Assemble piston (4) and connecting rod (2)

 Assemble piston (4) and connecting rod (2) so that the arrow is pointing in direction of travel (in opposite direction to power output).
The marking on the connecting rod (2) points towards the inlet side.

13

Push in piston pin (6) by hand

14

Insert circlip (5) for piston pin (6) into groove on piston (4)

 Do not damage piston (4). Use a clean cloth as a base.

15

Oil cleaned cylinder bores, connecting rod bearing journals, connecting rod bearing shells and pistons (4)

16

Fit on tensioning strap (7) for piston rings and tension

 Offset piston ring gaps 120°.

Tensioning strap

*000589041400

17

Install pistons (4) with arrow pointing in direction of travel (opposing the power output direction).

 Rotate crankshaft sufficiently so that the connecting rod (2) is not touching the connecting rod journal when the piston (4) is inserted into the cylinder bore.

 The marking on the connecting rod (2) is pointing toward the inlet side.

18

Inspect bolts (3)

AR03.10-P-6111-01HB

*BE03.10-P-1001-03D

19

Insert connecting rod bearing shell into connecting rod (2) and connecting rod bearing cap (1)

 Do not mix up top and bottom connecting rod bearing shells. Pay attention to the appropriate markings.

 The connecting rod bearing shell with the oil drilling must be installed in the connecting rod (2) otherwise the connecting rod bearing shells are not lubricated.

The anti-twist locks of the connecting rod bearing shells must be located in the slots of the connecting rods (2) and of the connecting rod bearing caps (1).

20

Screw on connecting rod bearing cap (1)

 Screw connecting rod bearing cap (1) and connecting rod (2) with the markings (arrows) pointing toward each other.

AR03.10-P-6111-02HB



*BA03.10-P-1001-01I

 External torx set

*001589760900

21

Rotate crankshaft and check for unobstructed movement

22

Install oil pump

AR18.10-S-6020C

23

Measure piston projection

 Install cylinder head gasket of normal thickness or cylinder head gasket of repair thickness depending on piston projection.

AR03.10-P-7041-01B

*BE03.10-N-1001-02P

24

Install cylinder head

AR01.30-S-5800D

Number

Designation

Engine
611.980

BE03.10-N-1001-02P

Piston projection (a) with new crankcase

-

mm

0.38 to 0.62

See picture

AR03.10-P-7041-01B

Number

Designation

Engine
611, 612.961/962/963/965/966/981,
613

BE03.10-P-1001-03D

Connecting rod bolt

Thread diameter

M

81

Shank length

New

mm

47 (0.3)

max.

mm

48

Number

Designation

Engine 611, 612 except 612.990, 613

BA03.10-P-1001-01I

Bolt, connecting rod bearing cap to connecting rod

Stage 1

Nm

5

Stage 2

Nm

25

Stage 3

°

90