Pistons and Connecting Rod Overview

Pistons and Connecting Rod Overview






1 Piston Rings

• Offset gaps by 120°

• Use piston ring pliers for removing and installing

• Identification "TOP" faces towards piston crown

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

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

2 Piston

• Checking, refer to => [ Pistons, Checking ] Testing and Inspection.

• Mark installed location to connecting rod and the cylinder to which it belongs

• Flatter side of piston crown faces toward center of cylinder block

• Piston, Installing, refer to => [ Piston, Installing ] Piston, Installing.

3 Circlip

4 Connecting Rod

• Only replace as set

• Affiliation to the cylinder mark - B -.

• Installed position: Markings - A - must align

5 Bearing Shell

• Note the installed position.

• Do not interchange used bearing shells

• Bearing shell retaining tabs must be firmly seated in the notches

• Axial clearance:

New: 0.05 to 0.31 mm

Wear limit: 0.40 mm

• Measure radial clearance using Plastigage:

New: 0.02 to 0.07 mm

Wear limit: 0.10 mm

• Do not turn crankshaft when measuring radial play.

6 Connecting Rod Bearing Cap

• Affiliation to the cylinder mark - B -.

• Installed position: the marks - A - must align

7 Bolt

• Replace

• 30 Nm + 90° (1/4) additional turn

• Lubricate the threads and contact surface

• Tighten to 30 Nm to measure radial play but do not turn further.

8 Cylinder Block

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

• Crankshaft, removing and installing, refer to => [ Crankshaft Overview ] Crankshaft Overview.

• Piston and cylinder dimensions, refer to => [ Piston and Cylinder Dimensions ] Piston and Cylinder Dimensions.

9 Piston Pin

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

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