Installing Valve-Stem Seals

Information 

• Position the pistons of the relevant cylinder at the bottom dead center  .
• Each piston is pressed downwards as pressure builds up in the cylinder  .

Information 

When required, all valve-stem seals on both cylinder rows must be replaced.

Information 

Protective caps must be ordered as separate spare parts. They are reusable. They are used to protect the valve-stem seal so that it is not damaged at the valve stem end.

1. Prepare valve-stem seal -1-  , protective cap -3-  and Assembly Driver 9606/1 -2-  .
   Fig 1: Identifying Valve-Stem Seal With Tool

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
2. Push protective cap onto valve stem end. → Protective cap 
   Fig 2: Identifying Valve-Stem Seals Protective Cap

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
3. Oil valve stem, protective cap and valve-stem seal. Push valve-stem seal with sealing lip upwards -1-  over the protective cap -2-  onto the valve stem. Remove protective cap.
   Fig 3: Locating Valve-Stem Seal Protective Cap And Valve-Stem Seal

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
4. Guide the Assembly Driver 9606/1  over the valve stem and fit the valve-stem seal by hand or by tapping it lightly using the rubber hammer as far as it will go. -arrow- 
   Fig 4: Pushing Valve-Stem Seal

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
5. Fit valve springs, concave washer and valve keys. To do this, place valve springs (there are two in the exhaust valve in the turbo engine) on the bottom concave washer. Place top concave washer in position.

   Information 

   The mechanic must practise for use of the assembly cartridge to be effective. Some repetitions must be made to ensure that the valve keys are correctly held in place.

6. Insert valve keys into the assembly cartridge.
   1. 6.1. Press the spring washer of the assembly fixture downwards -1-  and insert the valve key -2-  with the narrow end pointing downwards.
      Fig 5: Pressing Valve Key In Assembly Fixture

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.
   2. 6.2. Ensure that the valve keys fit symmetrically and are inserted as far as they will go in the tool. The spring washer automatically locks the valve keys in place.
   3. 6.3. Place the assembly cartridge -2-  onto the center of the assembly fixture. Observe installation position of the valve keys -1-  .
      Fig 6: Identifying Assembly Cartridge

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.
   4. 6.4. Press the assembly cartridge against the spring force onto the assembly fixture. The knurled screw moves forward. When doing so, turn the knurled screw back and forth until the valve keys snap into place. Repeat as required. → Assembly cartridge accepts the valve keysFig 7
      Fig 7: Assembling Valve Keys Cartridge

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.
   5. 6.5. Make sure the valve keys are held symmetrically in place in the assembly cartridge -1-  .
      Fig 8: Identifying Valve Keys

      Courtesy of PORSCHE CARS NORTH AMERICA, INC.
7. Place the valve key assembly cartridge onto the cylinder head (same as removal of valve) and position it on the top spring plate.
8. Press the assembly cartridge with the lever (assembly bar) against the force of the valve-spring and keep pressed. The knurled screw moves forward. When doing so, turn the knurled screw back and forth until the valve keys snap into place → Install valve keysFig 9. Repeat as required.
   Fig 9: Install Valve Keys

   Courtesy of PORSCHE CARS NORTH AMERICA, INC.
9. When installing the valve keys, check their correct positioning.
10. Replace all four valve-stem seals for a cylinder and refit valve keys. Only then fit compressed-air hose on the next cylinder and apply compressed air constantly.

Information 

• Before switching to another cylinder, the cylinder must be positioned at the bottom dead center and supplied with compressed air (see   1 )  .