Connecting Rod: Service and Repair

Pistons and connecting rods, disassembling and assembling

Note: Oil injector jet for piston cooling, Refer to Fig 8.

1. Connecting rod bolt - 30 Nm + 90° (1/4 additional turn)
^ Always replace
^ Grease thread and contact surface
^ Tighten to 30 Nm when measuring radial clearance] but do not turn further
2. Connecting rod bearing cap
^ Do not interchange
^ Mark allocation to cylinder using a color marker -B, Refer to Fig 5.
^ Observe when installing bearing cap: Tabs at contact surfaces at face of connecting rod must be aligned -A
^ Installed position of connecting rod pairs, Refer to Fig 7.
3. Bearing shell
^ Note installed position
^ Do not interchange run-in connecting rod bearing shells (mark)
^ Measuring radial play, Refer to Connecting Rod, Engine, Testing and Inspection.
^ Tighten bolts -item 1 to 30 Nm when measuring radial clearance] but do not turn further
4. Connecting rod
^ Replace only as a set
^ Mark allocation to cylinder using a color marker -B, Refer to Fig 5.
^ Observe when installing bearing cap: Tabs at contact surfaces at face of connecting rod must be aligned -A
^ Installed position of connecting rod pairs, Refer to Fig 7.
5. Snap ring
6. Piston pins
^ In case of difficulty of movement warm piston to approximately 60°C
^ When removing and installing] use VW222a Pilot drift
7. Pistons
^ Installed position and allocation piston/cylinder, Refer to Fig 5.
^ Arrow on piston head points to belt pulley side
^ checking, Refer to Fig 3.
^ Install with piston ring tension strip
^ Piston and cylinder dimensions, Refer to Piston, Engine, Specifications
^ Checking cylinder bore hole, Refer to Fig 4.
8. Piston rings
^ Shift by 120°
^ Use piston ring pliers to remove and install
^ Marking or identification "TOP" i e marked side must face toward the piston head
^ End play checking, Refer to Fig 1.
^ Height play checking, Refer to Fig 1.








Fig. 1 Checking piston ring end gap
^ Insert ring at a right angle to cylinder wall from above to lower cylinder opening approximately 15 mm cylinder edge. When inserting use pistons without rings

Fig. 2 Checking piston ring side clearance








^ Before measuring] clean piston ring groove

Fig. 3 Checking pistons
Special Tools and Equipment





^ External micrometer 75-100 mm
^ Measure approximately 10 mm from the lower edge at a 90°angle to piston pin axis.
^ Deviation from nominal dimension: maximum 0.04 mm
Specified dimension, Refer to Piston, Engine, Specifications, piston and cylinder measurements

Fig. 4 Checking cylinder bore
Special Tools and Equipment





^ Inner bore gauge 50-100 mm
^ Measure diagonally at 3 positions horizontally -A- and lengthwise -B-.
^ Deviation from nominal dimension: maximum 0.08 mm
Specified dimension, Refer to Piston, Engine, Specifications, piston and cylinder measurements





Fig. 5 Piston installed position and allocation piston/cylinder
^ Mark installed position and allocation to cylinder on piston head using chalk or water-proof felt pen.

Note: Do not use a center punch or scribe, since the piston head coating will be damaged.

^ Installation position:
Arrow on piston head points to belt pulley side





Fig. 6 Marking connecting rods
Note: Replace the connecting rods only as a set.

^ Do not interchange the connecting rod bearings.
^ Before removing mark allocation of connecting rod and connecting rod bearing caps to each other and to cylinder using a color marker (arrow).





Fig. 7 Installed position of connecting rods
^ Molded tabs (arrows) at the beveled surfaces of the connecting rod pairs 1 and 21 3 and 4 as well as 5 and 6 must point toward each other.





Fig. 8 Oil injector jet for piston cooling
1. Bolt- 10 Nm
2. Oil injector jet for piston cooling