Removing the piston with connecting rod

NOTE: TECHNICAL INFORMATION
Piston, piston pin, connecting rod and connecting rod bearing shells are matched to each other and balanced.
Always install the pistons, piston pins, connecting rods and connecting rod bearing shells in the cylinder from which they were removed.

NOTE: The description is provided only at one component. The procedure is the same for all other components.

NOTE: TECHNICAL INFORMATION
The work must be performed with vehicle care to prevent component damage.

Twist the crankshaft (2) into the position for disassembly.
Unscrew both connecting rod bolts (1) .
Remove the connecting rod bearing cap (3) with guide bearing shell.

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NOTE: TECHNICAL INFORMATION
For installation and dismantling of the connecting rods, it is essential for the crankshaft to be exactly in alignment with the cylinder bore.
Screw in the special tools 2 249 164 hand-tight into the threaded connection of the connecting rod bolts (1) .
Press out the piston with the connecting rod using special tool 2 249 164 .

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NOTE:
RISK OF DAMAGE
Damage on the cylinder wall and oil spray nozzles.
A large force can scratch the cylinder wall and bend the oil spray nozzles.
- Carefully shift the piston and connecting rod in the engine block.
Remove the piston and connecting rod in an upward direction.
Lever the connecting rod bearing shell (1) out of the connecting rod bearing cap (see arrows).

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Lever the connecting rod bearing (1) out of the connecting rod (see arrows).

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NOTE: The description is provided only at one component. The procedure is the same for all other components.
Measure the cylinder path.

TECHNICAL DATA SPECIFICATION

Engine in general, bore
		89 mm

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TECHNICAL DATA SPECIFICATION

Piston installation clearance (piston new)
Piston installation clearance (piston new)		0.003... 0.023 mm

TECHNICAL DATA SPECIFICATION

Permissible total wear tolerance between piston and cylinder (engine operated)
Piston installation clearance (piston worn)		0.25 mm

Check

Position micrometer in area (A) and measure piston installation clearance transversely to piston pin.

TECHNICAL DATA SPECIFICATION

Piston diameter
Measure the piston diameter at distance (A) from the lower end of the piston skirt.	Distance (A) to the lower end of the piston skirt	27 mm
	Nominal dimension of piston diameter	88.987 +0.02 -0.02 mm

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Result

Piston does not correspond to the specifications.

Measure

Replace piston.

Remove upper and middle piston ring (1) with a piston ring pliers (2) .

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Remove oil scraper ring (2) (U-Flex) by hand over the piston skirt (1) .

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Check the arrangement of the piston rings.
Piston ring (1)

Piston ring (2)

Oil scraper ring (3)

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Clean the ring zone on the piston.
Insert piston ring (1) in the annular groove on the piston and check it with feeler gauge (2) .

TECHNICAL DATA SPECIFICATION

Piston ring 1st groove A
Side clearance.		0.02... 0.07 mm

TECHNICAL DATA SPECIFICATION

Piston ring 1st groove H
Annular groove height.		1.21... 1.24 mm

TECHNICAL DATA SPECIFICATION

Piston ring 2nd groove A
Side clearance.		0.015... 0.06 mm

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TECHNICAL DATA SPECIFICATION

Piston ring 2nd groove H
Annular groove height.		1.51... 1.53 mm

TECHNICAL DATA SPECIFICATION

Piston ring 3. Groove-A DSF ring
Side clearance without spiral expander.		0.02... 0.06 mm

TECHNICAL DATA SPECIFICATION

Piston ring 3rd groove H
Annular groove height.		2.01... 2.03 mm