Connecting Rod: Description and Operation

Piston and Connecting Rod Overview


The crankshaft, piston, and connecting rods must not be replaced! Only removal and installation of these components is permitted.

• Secure the engine to the engine and transmission holder (VAS 6095) when working on it.






1 Bolt

• 30 Nm + 90° (1/4) additional turn

• Always replace

• Lubricate the threads and contact surface.

• Use the old bolts to measure the radial play.

2 Connecting Rod Bearing Cap

• Note the installed position.

3 Bearing Shell

• Note the installed position.

• Note the version: The upper bearing shell (to the piston) is made of wear-resistant material, identification: Black line on the contact surface in the area of the separating point.

• Do not interchange used bearing shells.

• Install the bearing shells in the center.

• Make sure it is tight

• Axial play wear limit: 0.37 mm

• Measure radial clearance using Plastigage: Wear limit: 0.08 mm. Do not rotate the crankshaft when checking the radial clearance.

4 Connecting Rod

• Marks matching the cylinder - arrow A -.

• Installed position: Marks - arrows B - point to the vibration damper side.

5 Circlip

6 Piston

• With a combustion chamber.

• Mark the installed position and cylinder allocation.

• Installed position and allocation, piston/cylinder. Refer to => [ Piston: Installed Position and Allocation, Piston/Cylinder ] Testing and Inspection.

• Directional arrow on the piston head points to the intake side.

• Install using a piston ring compressor.

• Checking piston position at Top Dead Center (TDC). Refer to => [ Piston Position, Checking at TDC ] Piston Position, Checking at TDC.

• Piston and cylinder dimensions. Refer to => [ Piston and Cylinder Dimensions ] [1][2]Specifications.

• Checking the cylinder bore, refer to => [ Cylinder Bore, Checking ] Testing and Inspection.

7 Piston Pin

• If difficult to move, heat the piston to 60 °C (140 °F).

• Remove and install using a pilot drift (VW 222 A).

8 Piston Rings

• Offset gaps by 120°

• Use piston ring pliers for removing and installing.

• "TOP" faces toward the piston crown.

• Checking the ring gap, refer to => [ Piston Ring Gap, Checking ] Testing and Inspection.

• Checking the piston ring groove clearance, refer to => [ Piston Ring Groove Clearance, Checking ] Testing and Inspection.