Piston and Connecting Rod, Disassembling and Assembling
Piston and connecting rod, disassembling and assembling
Piston And Connecting Rod, Disassembling And Assembling:
1 - Connecting rod bolt - 30 Nm plus an additional 1/4 (90 °)
^ Replace
^ Lubricate threads and contact surface
^ Use old bolt to measure radial play
^ Tighten to 30 Nm to measure radial play, do not turn further
2 - Pressure relief valve, 27 Nm
^ Opening pressure 1.6 to 1.9 bar
3 - Oil spray jet
^ For piston cooling
4 - Connecting rod bearing cap
^ Note installation position
^ Due to separation procedure (cracking) of connecting rod, cap only install in one position and only to corresponding connecting rod.
^ Affiliation to cylinder mark - B -
^ Installed location: Markings - A - point to belt pulley side
5 - Bearing shells
^ Upper bearing shell with oil hole for piston pin lubrication
^ Installed location
^ Do not interchange used bearing shells (mark)
^ Axial play new: 0.10 to 0.35 mm. Wear limit: 0.40 mm
^ Measure radial clearance with Plastigage: New: 0.02 to 0.06 mm. Wear limit: 0.09 mm. Do not turn crankshaft when checking radial clearance
6 - Connecting rod
^ Only replace as set
^ Affiliation to cylinder mark - B -
^ Installed location: Markings - A - point to belt pulley side
^ With oil hole for piston pin lubrication
7 - Circlip
8 - Piston pin
^ If difficult to move, heat piston to approx. 60 ° C
^ Use pilot drift VW 222 A for removal and installation
9 - Piston
^ Checking
^ Mark installed position and cylinder allocation
^ Arrow on piston face points toward belt pulley side
^ Install with piston ring compressor
^ Piston and cylinder dimensions Piston and cylinder dimensions
^ Cylinder bore, checking
10 - Piston rings
^ Offset gaps by 120 °
^ Use piston ring pliers for removal and installation
^ "TOP" mark must face up toward piston crown
^ Checking ring gap
^ Check piston ring groove clearance
Checking piston ring gap
- Push ring squarely from above down to approx. 15 mm from bottom end of cylinder. To do this use a piston without rings.
Checking ring to groove clearance
- Clean ring groove of piston before checking.
Checking piston
- Measure pistons approx. 10 mm from bottom edge and at points offset by 90 ° to piston pin axis.
^ Deviation from nominal dimension: max. 0.04 mm
Checking cylinder bores
Special tools, testers and auxiliary items required
^ Internal dial gauge 50 to 100 mm
- Measure diagonally at 3 positions transversely - A - and longitudinally - B -.
^ Deviation from nominal dimension: max. 0.08 mm
Installed position of bearing shell
Bearing shell - 1 - with connecting rod oil bore - arrow -.
Bearing shell - 2 - without connected rod cover oil bore.
- Place bearing shells centrally into connecting rod and connecting rod cover.
Dimension - a - must be the same at left and right.