Valve Guide Seal: Service and Repair
Valve Stem Seals
Special tools, testers and auxiliary items required
• Spark plug removal tool (3122 B)
• Valve seal removal tool (3364)
• Valve stem seal driver (3365)
• Valve cotter disassembly and assembly device (VAS 5161) with guide plate (VAS 5161/25)
• Adapter (T40012)
Procedure
• Engine removed.
- Remove camshafts => [ Camshafts ] Camshafts.
- Using spark plug removal tool (3122 B), remove spark plugs.
- Place drift (VAS 5161/3) on valve plate and loosen stuck valve keepers using a plastic hammer.
- Place guide plate (VAS 5161/25) from valve cotter disassembly and assembly device (VAS 5161) on cylinder head.
- Secure guide plate with a nut.
- Screw adapter (T40012) with gasket by hand into respective spark plug thread and apply constant pressure.
• Minimum pressure: 6 bar positive pressure.
Procedure for outer rows of valves:
- Screw engaging device (VAS 5161/6) with installation fork (VAS 5161/5) into guide plate.
- Push installation cartridge (VAS 5161/8) into guide plate.
- Hook in pressure fork (VAS 5161/2) at engaging device and press down installation cartridge.
- At the same time, turn knurled bolt of installation cartridge to the right, until the points engage in the valve keepers.
- Lightly move knurled bolt back and forth, causing the valve keepers to be pressed apart and be captured in the installation cartridge.
- Release pressure fork.
- Take out installation cartridge.
- Remove guide plate and turn it aside.
• Pressurized air hose remains connected.
- Remove valve spring with valve plate.
Procedure for inner rows of valves:
- Screw engaging device (VAS 5161/6) with installation fork (VAS 5161/5) onto cylinder head.
- Push knurled spacer ring (VAS 5161/17) onto installation cartridge (VAS 5161/8).
- Push installation cartridge into guide plate.
- Hook in pressure fork (VAS 5161/2) at engaging device and press down installation cartridge.
- At the same time, turn knurled bolt of installation cartridge to the right, until the points engage in the valve keepers.
- Lightly move knurled bolt back and forth, causing the valve keepers to be pressed apart and be captured in the installation cartridge.
- Release pressure fork.
- Take out installation cartridge.
- Remove guide plate and turn it aside.
• Pressurized air hose remains connected.
- Remove valve spring with valve plate.
Continued for all rows of valves:
- Pull off valve stem oil seals using Valve Seal Removal Tool (3364).
• For pressing on green-colored valve stem seals from delivery program, the valve stem seal driver (3365) must be drilled to 10.5 mm dia.
• Mark the drilled driver for later reuse.
• A plastic sleeve - A - is supplied with the new valve shaft seals.
- Place plastic sleeve - A - on valve stem to prevent damage to new valve stem seals - B -.
- Lightly coat sealing lips of valve stem seal with oil.
- Push valve stem seal onto plastic sleeve.
- Carefully press valve stem oil seal onto valve guide using (3365).
- Remove plastic sleeve again.
If the valve keys were removed from the installation cartridge, they must be inserted into insertion device (VAS 5161/18) next.
• The large diameter of the valve keepers point upward.
- Install valve spring and valve plate.
Installed position of valve spring:
• The larger diameter - arrow - faces toward cylinder head.
Procedure for outer rows of valves:
- Fasten the guide plate to cylinder head again as shown in illustration.
- Insert installation cartridge into guide plate.
- Press the pressure fork down and pull the knurled bolt upward while turning it left and right to insert the valve cotters.
- Release pressure fork with the knurled bolt still pulled.
Procedure for inner rows of valves:
- Insert installation cartridge with knurled spacer wheel into guide plate.
- Press the pressure fork down and pull the knurled bolt upward while turning it left and right to insert the valve keepers.
- Release pressure fork with the knurled bolt still pulled.
- Install camshafts => [ Installing ] Camshafts.
• After installing the camshafts, the engine may not be started for approximately 30 minutes. The hydraulic adjusting elements must seat themselves (otherwise the valves will seat themselves on the pistons).
• After working on the valvetrain and lifters, carefully rotate the crankshaft by hand at least 2 full revolutions before starting to be sure that valves do not strike the pistons.
Tightening Specifications
