Overview - Pistons And Connecting Rod

Fig 1: Exploded View Of Pistons And Connecting Rod

Courtesy of AUDI OF AMERICA, LLC

1. Bolts
   • 50 Nm + 90°
   • Replace after removing
   • Use the old bolts for radial clearance measurement
   • Oil the threads and contact surface
2. Connecting Rod Bearing Cap
   • Use color to identify the cylinder and connecting rod to which it belongs. Refer to Fig 6.
   • Installation position of the connecting rod pairs. Refer to Fig 7.
3. Bearing Shells
   • Make sure the retaining tabs are secure.
   • Replace any worn bearing shells
4. Connecting Rod
   • Always replace as a set
   • Use color to identify the cylinder and the connecting rod bearing cap to which it belongs. Refer to Fig 6.
   • Installation position of the connecting rod pairs. Refer to Fig 7.
   • Axial play for each connecting rod pair: 0.30 to 0.54 mm
   • Radial play, measuring. Refer to CONNECTING RODS, CHECKING RADIAL CLEARANCE .
5. Circlip
   • Replace after removing
6. Piston Pin
   • Removing and Installing. Refer to PISTONS, REMOVING AND INSTALLING .
7. Piston
   • Label the installation position and cylinder allocation. Refer to Fig 5.
   • Replace the piston if there are cracks on the piston crown or piston shaft
   • Install with the Funnel: T40369 
   • Removing and Installing. Refer to PISTONS, REMOVING AND INSTALLING .
   • Check piston and cylinder bore. Refer to PISTON AND CYLINDER BORE, CHECKING .
8. Circlip
   • Replace after removing
9. Compression Ring
   • Install using the Piston Ring Pliers: VAS211003  . Refer to Fig 3.
   • Measuring the gap. Refer to Figure.
   • Measuring side clearance. Refer to Figure.
   • Allocation and installation position. Refer to Fig 2.
   • Offset gaps by 120° to -item  : Compression Ring
10. Compression Ring
    • Install with Piston Ring Pliers: VAS211003  . Refer to Fig 3.
    • Measuring the gap. Refer to Figure.
    • Measuring side clearance. Refer to Figure.
    • Allocation and installation position. Refer to Fig 2.
    • Offset gaps by 120°
11. Oil Scraping Ring
    • Carefully remove and install the three-part oil scraping ring by hand
    • Installation position. Refer to Fig 4.
    • Piston ring gap is not measurable
    • Height clearance cannot be measured
    • Allocation. Refer to Fig 2.
12. Oil Spray Jet
    • With spray nozzle valve
    • Do not bend
    • Removing and Installing. Refer to OIL SPRAY JETS, REMOVING AND INSTALLING .
13. Banjo Bolt
    • 10 Nm +45°
    • Replace after removing

Allocation and Piston Ring 

Fig 2: Allocation Of The Piston Ring On Connection With The Three Part Oil Scraping Ring.

Courtesy of AUDI OF AMERICA, LLC

1. Compression ring with bevel -arrow A- on the inside upper side
2. Compression ring offset -arrow B- on the bottom outside
3. Three Part Oil Scraping Ring

Installing the Compression Ring 

Fig 3: Installing Compression Ring

Courtesy of AUDI OF AMERICA, LLC

• Only open the compression ring -2- using the Piston Ring Pliers: VAS211003  only until it can be pushed over the pistons -1-.

Installing the Oil Scraping Ring 

Fig 4: Install The Three Part Oil Scraping Ring

Courtesy of AUDI OF AMERICA, LLC

-- Pay attention to the spring installation position:

• The plunger of the plates -2 and 3- and the spring -1- must be offset 90° to each other.

-- Install by hand.

Installation sequence: 

-- Insert the spring -1- in the groove.

-- Insert the lower plate -3- in the groove.

-- Insert the upper plate -2- in the groove.

• Install the upper joint of the 3-part oil scraping ring 120° offset to the neighboring compression ring

Piston Installed Position 

Fig 5: Piston Installed Position

Courtesy of AUDI OF AMERICA, LLC

Installation position: 

arrow -  To the belt pulley side

x -  Cylinder bank identification: L = left, R = right

Connecting Rod, Marking 

Fig 6: Identifying Mark Connecting Rod

Courtesy of AUDI OF AMERICA, LLC

-- Mark the connecting rod and connector rod bearing cap to each other and to the cylinder -arrow- with paint for reinstallation.

Connecting Rod Installation Position 

Fig 7: Connecting Rod, Installed Location

Courtesy of AUDI OF AMERICA, LLC

• The molded tabs at the beveled surfaces -arrows- of the connecting rod pairs must point toward each other.