Pistons and Connecting Rods, Assembly Overview

Pistons and connecting rods, assembly overview





1 - Piston rings
^ Offset gaps by 120°
^ Use piston ring pliers for removal and installation
^ "TOP" faces toward piston crown
^ Checking ring gap
^ Check piston ring groove clearance

2 - Piston
^ With combustion chamber
^ Mark installed position and cylinder allocation
^ Installed position and allocation, piston/cylinder
^ Arrow on piston face points toward belt pulley side
^ Install with piston ring compressor
^ Replace if piston skirt is cracked

3 - Piston pin
^ If difficult to move, heat piston to 60°C
^ Use VW 222a for removal and installation

4 - Circlip

5 - Connecting rod
^ Only replace as set
^ Mark affiliation to cylinder - A -
^ Installed location: Markings - B - point to belt pulley side

6 - Bearing shell
^ Note installed position
^ Observe design: upper bearing shell (toward piston) of wear-resistant material, Distinguishing feature: Black stripe on running surface in area of separating point
^ Do not interchange used bearing shells
^ Install bearing shells centrally
^ Ensure seated tightly
^ Axial play wear limit: 0.37 mm
^ Measure radial play with Plastigage, Wear limit: 0.08 mm. Do not turn crankshaft when checking radial clearance

7 - Cylinder block
^ Cylinder bore, checking

8 - Connecting rod bearing cap
^ Note installed position

9 - Oil spray jet
^ For piston cooling

10 - 25 Nm
^ Install without sealant

11 - Connecting rod bolt, 30 Nm plus an additional 1/4 turn (90°)
^ Replace
^ Lubricate threads and contact surface
^ Use old bolt to measure radial play