Valve Stem Seals, Cylinder Head Installed, Replacing
Valve Stem Seals, Cylinder Head Installed, Replacing
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 5161/19 A)
• Adapter (T40012)
Procedure
- Remove camshafts. Refer to => [ Camshafts ] Camshafts.
- Mark positioning of the roller rocker lever and hydraulic adjusting elements for re-installation.
- Remove roller rocker lever together with the hydraulic adjusting elements and place them on a clean surface.
- Using spark plug removal tool (3122 B), remove spark plugs.
- Move piston for respective cylinder to "Bottom Dead Center (BDC) position".
- Place drift (VAS 5161/3) on valve spring plate and loosen stuck valve keepers using a plastic hammer.
- Place guide plate (VAS 5161/19 A) from valve cotter disassembly and assembly device (VAS 5161) on cylinder head.
- Secure guide plate with knurled screws (VAS 5161/12 ).
- Install adapter (T40012) with gasket by hand into respective spark plug thread and apply constant pressure.
• Minimum pressure: 6 bar positive pressure.
- Install 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.
- Unfasten guide plate and turn it aside.
• Pressurized air hose remains connected.
- Remove valve spring with valve spring plate.
- Pull off valve stem oil seals using Valve Seal Removal Tool (3364).
If Valve Seal Removal Tool (3364) cannot be used, on several valve stem seals due to restricted clearance, proceed as follows:
- Using a drift, drive out roll pin - arrow - at Valve Seal Removal Tool (3364) and remove impact puller attachment.
- Place lower part of the Valve Seal Removal Tool ( 3364) on valve stem seal.
- Secure Valve Seal Removal Tool (3364) with a drift or cotter pin driver - 1 -, as shown in the illustration.
- Place valve lever on Valve Seal Removal Tool ( 3364) and pull off valve stem seal - arrow -.
• 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 keepers were removed from the installation cartridge, they must then be inserted into valve keeper insertion device (VAS 5161/18).
• The large diameter of valve keepers point upward.
- Press assembly cartridge onto valve keepers insertion device and capture the valve keepers.
- Install valve spring and valve spring plate.
• The tight spring coils - arrow - face toward cylinder head.
- Install guide plate onto cylinder head again.
- Insert installation cartridge into guide plate.
- Press pressure fork down and pull knurled bolt upward while turning it left and right to insert the valve keepers.
- Release pressure fork with the knurled bolt still pulled.
- Repeat procedure on each valve.
Assembling
Assembly is in reverse order of removal, noting the following:
- Make sure all the roller rocker levers seat properly on the valve stem ends and are clipped onto the respective hydraulic adjusting elements.
- Install camshafts. Refer to => [ Camshafts ] Camshafts.
- Install spark plugs.