Removing and installing valve stem seals (cylinder head removed)

Special tools and workshop equipment required

Engine and gearbox support -VAS 6095-

Cylinder head tensioning device -VAS 6419-

Valve stem pliers -VAS 6770-

Valve stem seal fitting tool -3365-

Procedure

• Removing cylinder head → Chapter
• Insert cylinder head tensioning device -VAS 6419- into engine and gearbox support -VAS 6095-.
• Tension cylinder head on cylinder head tensioning device as shown in illustration.
• Connect cylinder head tensioning device to compressed air.
• Use lever -arrow- to slide air cushion under combustion chamber from which valve stem seals are to be removed.
• Allow compressed air to flow into air cushion until it lies against valve disc.

• Fit guide plate -VAS 5161A/32-1- onto cylinder head and secure with knurled screws -VAS 5161/12-.
• Insert punch -VAS 5161/3A- into guide plate and use a plastic hammer to knock loose the firmly seated valve cotters.

• Screw toothed piece -VAS 5161/6- with hooking fork -VAS 5161/5- into guide plate.
• Slide sleeve -VAS 5161A/32-2- onto assembly cartridge and insert cartridge into guide plate -VAS 5161A/32-3-.
• Attach pressure fork -VAS 5161/2- to toothed piece and press assembly cartridge down.
• At the same time, turn knurled screw of assembly cartridge clockwise until tips engage in valve cotters.
• Move knurled screw back and forth to press apart valve cotters and capture them in assembly cartridge.
• Release pressure fork.
• Remove installation cartridge.
• Unbolt guide plate and move to side.
• Remove valve spring and valve spring plate.

• Pull off valve stem seal using valve stem pliers -VAS 6770-.

Risk of damage when installing valve stem seals.

• Place plastic sleeve -A-, enclosed with new valve stem seals -B-, onto valve stem.
• Lightly oil sealing lip of valve stem seal.
• Push valve stem seal onto plastic sleeve.
• Carefully press valve stem seal onto valve guide using valve stem seal fitting tool -3365-.
• Remove plastic sleeve.

Larger diameter of valve cotters faces upwards.

• Press assembly cartridge onto insertion device from above and pick up valve cotters.
• Insert valve spring and valve spring plate. For installation position of valve spring refer to → Fig..

• Bolt guide plate -VAS 5161A/32-1- onto cylinder head again.
• Insert assembly cartridge -VAS 5161A/32-2- with sleeve -VAS 5161A/32-3- into guide plate.
• Press pressure fork downwards and pull knurled screw upwards, turning it clockwise and anticlockwise. This inserts the valve cotters.
• Reduce pressure on pressure fork whilst pulling on knurled screw.
• Repeat procedure on each valve.
• Installing cylinder head → Chapter.