Removal and Replacement
Piston and Connecting Rod Overview
1 Bolt
• 30 Nm + 90° (1/4) additional turn.
• Always replace.
• Lubricate the threads and contact surface.
• Tighten to 30 Nm to measure the radial play, do not tighten the additional turn.
2 Pressure Relief Valve
• 27 Nm
• Opening pressure 1.3 to 1.6 bar.
3 Oil Spray Jet
• For the piston cooling.
4 Connecting Rod Cap
• Pay attention to the installed position.
• Due to the way the separated connecting rod breaks (cracks), the cap fits only in one position and only onto the respective connecting rod.
• Affiliation to the cylinder mark - B -.
• Installed position: The marks - A - point to belt pulley side.
5 Bearing Shell
• Note the installed position, refer to => [ Bearing Shell Installed Position ].
• Do not interchange used bearing shells (mark them).
• Axial play new: 0.10 to 0.35 mm.
Wear limit: 0.4 mm.
• Measure the radial clearance using Plastigage:
New: 0.02 to 0.06 mm.
Wear limit: 0.09 mm.
Do not rotate the crankshaft when measuring the radial play.
6 Connecting Rod
• With a cracked bearing cap.
• Separating a new connecting rod. refer to => [ New Connecting Rod, Separating ] Procedures.
• Only replace as a set.
• Affiliation to the cylinder mark - B -.
• Installed position: The marks - A - point to belt pulley side.
7 Circlip
8 Piston Pin
• If difficult to move, heat the piston to 60 °C (140 °F).
• Remove and install using a pilot drift (VW 222 A).
9 Piston
• Checking, refer to => [ Pistons, Checking ] Testing and Inspection.
• Mark the installed position and the cylinder allocation.
• The arrow on the piston face points toward the belt pulley side.
• Install using a piston ring compressor.
• Cylinder bore, checking. Refer to => [ Cylinder Bore, Checking ] Testing and Inspection.
• For the correct piston and cylinder dimensions, refer to => [ Piston and Cylinder Dimensions ] Piston and Cylinder Dimensions.
10 Piston Rings
• Offset gaps by 120°
• Use piston ring pliers for removal and installation.
• Marks face toward the piston crown.
• Ring gap, checking. Refer to => [ Piston Ring Gap, Checking ] Testing and Inspection.
• Piston ring groove clearance, checking. Refer to => [ Piston Ring Groove Clearance, Checking ] Testing and Inspection.
Bearing Shell Installed Position
The bearing shell - 1 - with a oil bore - arrow - is for the connecting rod.
The bearing shell - 2 - without a oil bore is for the connecting rod cap.
- Place the bearing shells centrally into the connecting rod and cap.
Dimension - a - must be the same on the left and right sides.