Piston and Connecting Rod Assembly Overview
Piston and Connecting Rod Assembly Overview
1 Piston Rings
• Offset the gaps by 120 degrees.
• Use piston ring pliers for removal and installation.
• Identification "TOP" faces towards the piston crown.
• Checking ring gap, refer to => [ Piston Ring Gap, Checking ] Testing and Inspection.
• Checking 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 the installed location to the connecting rod and the affiliation to the cylinder.
• Flatter side of piston crown faces toward the center of the cylinder block.
• Installing piston, refer to => [ Piston, Installing ] Piston, Installing.
3 Circlip
4 Connecting Rod
• Only replace as a set.
• Affiliation to the cylinder mark - B -.
• Installation position: Markings - A - must align.
5 Bearing Shell
• Note the installation position.
• Do not interchange the 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 with Plastigage:
New: 0.02 to 0.07 mm
Wear limit: 0.10 mm
• Do not turn the crankshaft when measuring radial play.
6 Connecting Rod Bearing Cap
• Affiliation to the cylinder mark - B -.
• Installation position: Markings - A - must align.
7 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, but do not turn further.
8 Cylinder Block
• Checking cylinder bore, refer to => [ Cylinder Bore, Checking ] Testing and Inspection.
• Crankshaft assembly overview, refer to => [ Crankshaft Assembly Overview ] Crankshaft Assembly Overview.
• Piston and cylinder dimensions, refer to => [ Piston and Cylinder Dimensions ] Piston and Cylinder Dimensions.
9 Piston Pin
• If difficult to move, heat the piston to 60 °C (140 °F).
• Remove and install using a pilot drift (VW 222A ).