Audi Workshop Service and Repair Manuals

• 30 Nm +1/4turn (90°) further
• ◆ Renew conrod bolts (Item 13)
• ◆ Oil threads and contact surface
• ◆ To measure radial clearance tighten to 30 Nm but not further
• Pressure relief valve, 27 Nm
• ◆ opens at:
  2.5 ... 3.2 bar
• Oil spray jet
• ◆ For piston cooling

• Conrod bearing cap
• ◆ Mark cylinder number -B-
• ◆ Installation position:
  Marking -A- faces towards pulley end
• Bearing shell
• ◆ Note installation position
• ◆ Do not interchange used bearing shells (mark)
• ◆ Ensure retaining lugs fit tightly in recesses
• ◆ Axial clearance
  New: 0.10...0.35 mm
  Wear limit: 0.40 mm
• ◆ Check radial clearance with Plastigage:
  New: 0.01...0.05 mm
  Wear limit: 0.12 mm
  Do not rotate crankshaft when checking radial clearance
• ◆ To measure radial clearance, tighten nuts -Item 1- to 30 Nm but do not turn further

• Cylinder block
• ◆ Checking cylinder bores
  =>Fig. 4
• ◆ Piston and cylinder dimensions
  =>Page 13-78
• Bearing shell
• ◆ With oil drilling for piston pin lubrication
• ◆ Note installation position
• ◆ Do not interchange used bearing shells (mark)
• ◆ Axial clearance
  New: 0.10...0.35 mm
  Wear limit: 0.40 mm
• ◆ Check radial clearance with Plastigage:
  New: 0.01...0.05 mm
  Wear limit: 0.12 mm
  Do not rotate crankshaft when checking radial clearance
• ◆ To measure radial clearance, tighten nuts -Item 1- to 30 Nm but do not turn further

• Conrod
• ◆ Only renew as a set
• ◆ Mark cylinder number -B-
• ◆ Installation position:
  Marking -A- faces towards pulley end
• ◆ With oil drilling for piston pin lubrication
• Circlip
• Piston pin
• ◆ If difficult to move, heat piston to approx. 60 °C
• ◆ Remove and install with VW 222a

• Piston ring
• ◆ Offset gaps by 120 °
• ◆ Remove and install with piston ring pliers
• ◆ "TOP" must face towards piston crown
• ◆ Checking ring gap=> Fig. 1
• ◆ Checking ring to groove clearance
  => Fig. 2
• Piston
• ◆ Checking => Fig. 3
• ◆ Mark installation position and cylinder number
• ◆ Arrow on piston crown points to pulley end
• ◆ Install using piston ring clamp
• Conrod bolt
• ◆ Renew

→ Fig. 1    Checking piston ring gap

• ‒ Push ring squarely from above down to approx. 15 mm from bottom end of cylinder.

→ Fig. 2    Checking ring to groove clearance

• ‒ Clean groove before checking clearance.

→ Fig. 3    Checking piston

• ‒ Measure pistons approx. 10 mm from lower edge of skirt, at 90° to the piston pin axis.
• ‒ Deviation from nominal dimension
  not more than 0.04 mm

→ Fig. 4    Checking cylinder bores

• ‒ Use internal dial gauge 50 ... 100 mm.
• ‒ Take measurements at 3 positions in both lateral -A- and longitudinal -B- directions.
• ‒ Deviation from nominal dimension
  not more than 0.08 mm