Disassembling Pistons

→ Do not overstretch piston rings with piston ring pliers. Spread the piston ring until it just fits over the piston.

Information 

• If reusing a piston, do not remove combustion residues on the piston crown are mechanically! 
  Fig 1: Identifying Piston And Connecting Rod

  Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. Piston-Ring Set; Oil With Engine Oil; TOP Marking Facing Upwards; Oil Scraper Ring Down; Ring Gaps Offset By 120°
2. Piston; Different On Naturally Aspirated And Turbo Engines; Combustion Chamber Recess Facing Centre Of Engine; Left And Right Different; Direction Of Travel Arrow In Direction Of Travel
3. Piston-pin Circlip (Positioned At 6 O'clock Or 11 O'clock)
4. Piston pin; Oil
5. Connecting Rod
6. Connecting Rod Bolt; Replace As It Must Be Tightened In The Plastic Area; Oil Screw
7. Connecting Rod Bearing Shells; Oil With Engine Oil

Fig 2: Identifying Connecting-Rod Assembly And Bearing Shells

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. View A (Identification Area For Connecting-Rod Number; Fit Connecting Rod With Identification Area Facing Exhaust Side; Markings On Rod And Cap Must Be On The Same Side)
2. View B (Fit Bearing Shells Flush And Press In By Hand)
3. View C (Fit Bearing Shells Flush And Press In By Hand)

Fig 3: Identifying Piston Classification - Naturally Aspirated Engine

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. Marking For Dimension Group (Just One Permitted Per Engine, In This Case x)
2. Porsche Short Numeric Code Without Main Or Middle Number
3. Short Numeric Code (Supplier)
4. Marking Area For Weight Group (Just One Permitted Per Engine, + Or -)
5. Cylinder Bank Identification (V6 1-3 And 4-6) (V8 1-4 And 5-8)
6. Barcode 128 (Short Numeric Code Without Main Group Or Weight Group)
7. Arrow Marking In Direction Of Travel
8. Identification For Dimension Group
9. Arrow Marking In Direction Of Travel
10. Inspection Stamp (Supplier)

Fig 4: Identifying Piston Classification - Turbo Engine

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

1. Arrow Marking In Direction Of Travel
2. Porsche Short Numeric Code Without Main Or Middle Number
3. Short Numeric Code (Supplier)
4. Cylinder Bank Identification (V8 1-4 And 5-8)
5. Marking Area For Weight Group (Just One Permitted Per Engine, + Or -)
6. Barcode 128 (Short Numeric Code Without Main Group Or Weight Group)
7. Arrow Marking In Direction Of Travel
8. Marking For Dimension Group (Just One Permitted Per Engine, In This Case x)
9. Marking Area For Weight Group (Just One Permitted Per Engine, + Or -)
10. Inspection Stamp (Supplier)

Information 

• When disassembling the piston/connecting rod unit, note or mark the position, relationship to cylinder and installation position using a waterproof felt tip pen  .

1. Secure piston on Retaining Device 9597  (→ Piston on retaining device  ).
   Fig 5: Identifying Piston On Retaining Device

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
2. Remove both piston-pin circlips using a small screwdriver. To do this, guide the screwdriver through the small cut-out and carefully lever out the piston-pin circlip → Levering out piston-pin circlips with a small screwdriver  .
   Fig 6: Removing Piston-Pin Circlips Using Screwdriver

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
3. Insert piston into the Retaining Device 9597  (leave space below for the piston pins) and drive out piston pins using a suitable pressure piece. → Piston pin with plunger 
   Fig 7: Inserting Piston Pin With Plunger

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
4. Remove connecting rod from the piston and place to one side.

   Information 

   • Compression rings and oil scraper rings are installed and removed differently  .
5. Remove piston rings.
   1. 5.1. Place the piston on a clean surface and look for the gaps in the piston rings.
   2. 5.2. Remove the piston rings, starting at the piston crown. To do this, move the middle point of Piston Ring Pliers Gr. 1 Nr. 58  into the gap in the relevant ring. The holding arms of the piston ring pliers should clasp the piston ring from above → Piston ring pliers on piston ring  . Only open the piston ring as much as is needed to remove the piston ring from the groove. Do not overstretch it!
      Fig 8: Removing Piston Ring

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.
   3. 5.3. Relieve the piston ring pliers and remove the piston ring from the pliers.
   4. 5.4. Remove the two-piece oil scraper ring as follows: First, remove the outer ring by hand by carefully prying it away from the piston. Then remove the inner oil scraper spring in the same way.