Connecting Rod: Service and Repair

Pistons and Connecting Rods, Disassembling and Assembling

Note:

- Mount in engine stand VW 540 before beginning work.






1. Piston ring
^ Offset gaps by 120°
^ Remove and install using piston ring pliers
^ "TOP" faces piston crown
2. Piston
^ Mark installation position and cylinder number
^ Arrow on piston crown points to pulley end
^ Install using piston ring clamp
3. Connecting rod
^ Only replace as a set
^ Mark cylinder number -B
^ Installation position: Marking -A- faces towards pulley end
4. Connecting rod bolt
^ For Engine code AEG
5. Connecting rod bearing cap
^ Mark cylinder number -B
^ Installation position: Marking -A- faces towards pulley end
6. 30 Nm (22 ft. lbs.) + 1/4 turn (90°)
^ For Engine code AEG
^ Oil threads and contact surfaces
^ To measure radial clearance tighten to 30 Nm (22 ft. lbs.) but no further
^ 90° additional angle can be measured with torque angle meter i.e., Hazet 6690
7. 30 Nm (22 ft. lbs.) + 1/4 turn (90°)
^ Engine codes AVH, AZG
^ Always replace
^ Oil threads and contact surfaces
^ To measure radial clearance tighten to 30 Nm (22 ft. lbs.) but no further
^ 90° additional angle can be measured with torque angle meter i.e., Hazet 6690
8. Pressure relief valve
^ 27 Nm (20 ft. lbs.)
^ Opening pressure: 2.5 to 3.2 bar (36 to 46 psi)
9. Oil spray jet
^ For piston cooling
10. Bearing shell
^ Note installation position
^ Do not interchange used bearing shells
^ Ensure retaining lugs fit tightly in recesses

- Axial clearance
^ New: 0.05 to 0.35 mm
^ Wear limit: 0.37 mm

- Check radial clearance with Plastigage:
^ New: 0.01 to 0.06 mm
^ Wear limit: 0.12 mm
^ Do not rotate crankshaft when checking radial clearance

11. Engine block
12. Circlip
13. Piston pin
^ If difficult to remove, heat piston to 60°C (140°F)
^ Remove and install using VW 222a