Installing Valves

NOTIFICATION 

Valve grinding paste not removed 

• Risk of damage to sealing face on intake valve 
  1. → Remove all valve grinding paste fully after grinding. Information

Information 

• The valves cannot be touched up afterwards. 
• The valves can be grinded using commercially available valve grinding paste. 

1. Apply a small amount of valve grinding paste to the valve seat.
2. Oil the valve stem of a new valve and insert it into the valve guide from the combustion chamber. Push the valve in until it is seated securely in the valve seat of the cylinder head.
3. Grind the valve with a commercially available valve grinder (with rubber suction head) using rotating movements. To do this, hold the valve grinder between the palms of both hands and press against the valve seat with rotating movements Grinding valve seat. 

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   Grinding valve seat

4. Carry out the grinding operation for each valve that is replaced. Check for leaks using some fuel and installed spark plugs. The fuel must not escape through the valve seat. Carefully remove valve grinding paste.
5. Fit valve lock. Locking valves 

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   Locking valves

6. Replace valve stem seals. For details, see

   > 156355 REPLACING VALVE-STEM SEALS 

7. Fit valve springs, concave washers and valve keys. To do this, place valve springs (there are two in the outlet 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.

8. Insert valve keys into the assembly cartridge.

   Press the spring washer of the assembly fixture downwards -1-  and insert the valve keys -2-  with the narrow end pointing downwards.

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   Valve keys in assembly fixture

   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.

   Place the assembly cartridge -3-  onto the centre of the assembly fixture. Observe installation position of the valve keys

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   Fitting assembly cartridge

   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 with vaive keys 

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   Assembly cartridge with valve keys

   Make sure the valve keys are held symmetrically in place in the assembly cartridge -1-  .

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   Valve keys inserted

9. Place the valve key assembly cartridge onto the cylinder head (same as removal of valve) and position it on the top concave washer.
10. Press assembly cartridge with the lever (assembly bar) against the force of the valve spring and keep It pressed. The knurled screw moves forward. When doing so, turn the knurled screw back and forth until the valve keys snap Into place Installing valve keys. Repeat as required.

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    Installing valve keys

11. When installing the valve keys, check that they are positioned correctly.