Removing and Installing Cylinder Head - Engine Removed
Removing and installing cylinder head - engine removedTools
Preliminary work for removing cylinder head
1. Remove exhaust manifold. Remove old seal.
2. Remove cylinder head cover.
3. Remove camshafts.
ATTENTION: Interchanged or dirty flat-base tappets.
^ Damage to engine components
^ The components have been run in the fitting bores in the housing, therefore do not interchange them.
^ Pay attention to cleanliness.
Note: There must be no visible signs of wear on the flat-base tappets and fitting bores of the flat-base tappet housing.
4. Remove the flat-based tappets. Pull each of the components out of the flat-base tappet housing using a strong magnet. Check running surfaces for signs of damage. To avoid confusing the individual flat-based tappets, lay them on a labelled, clean surface.
5. Remove flat-base tappet housing. Unscrew 11 Torx screws -1- from the outside to the inside. Remove housing and check the fitting bores for damage.
6. Remove the old O-rings at the spark-plug recesses.
Removing cylinder head
ATTENTION: Risk of damage due to particles of dirt.
^ Oil bores/oil ducts can become blocked up.
^ When working on the engine, absolute cleanliness is essential.
^ Lay removed engine parts on a clean base and cover them without fail.
^ Use the cover for dust protection when fitting the engine NR.165 on the engine assembly support.
Cylinder head 1-3:
1. Unscrew M6 threaded bolt (hexagon socket) for guide rail (flywheel side) -1-.
2. Unscrew four Torx screws with M6 30 captive washers (10.9) -1-4- at the chain slot. Use of a magnetic bit is recommended so that the screw to be fitted in the slot -item - cannot fall into the crankcase.
3. Loosen and unscrew 12 M10 Torx cylinder-head screws from outside to inside.
4. Carefully lift off the cylinder head and remove the old cylinder-head gasket.
5. Carefully clean the sealing faces on the cylinder head and crankcase (e.g. using a nylon brush and a clean, lint-free cloth soaked in acetone). Check the sealing face from cylinder head to crankcase for damage and cracks, and rework the flat surface if necessary.
The removal of cylinder head 4-6 is the same as for side 1-3 with the following change
- The threaded bolt for guide rail 4-6 on the cylinder head (belt pulley side) -1- is removed even before the camshaft timing gears are removed.
Installing cylinder head
ATTENTION: Risk of damage due to particles of dirt.
^ Oil bores/oil ducts can become blocked up.
^ When working on the engine, absolute cleanliness is essential.
^ Lay removed engine parts on a clean base and cover them without fail.
^ Use the cover for dust protection when fitting the engine NR.165 on the engine assembly support.
Fitting cylinder head side 1 - 3:
1. Turn the crankcase at the assembly support in such a way that side 1-3 stands vertically upwards.
2. Fit new cylinder-head gasket. The inscription "OBEN/ TOP" must be clearly visible.
3. Carefully position the cylinder head on the crankcase. Pay attention to the dowel sleeves.
4. Screw in 12 M10 Torx screws evenly and tighten according to the prescribed tightening sequence -1-12-. - Initial tightening: 22 ft. lb., loosen all screws in reverse tightening sequence; - Initial tightening: 15 ft. lb.; - Final tightening, 2 torque angle: 70°
5. Screw in and tighten four Torx screws with M6 30 captive washers (10.9) -1-4- at the chain slot. Use of a magnetic bit is recommended so that the screw to be fitted in the slot -item - cannot fall into the crankcase. Tightening Torque: 9.5 ft. lb.
6. Fit threaded bolt for guide rail -1- with a new O-ring at the cylinder head. Tightening Torque: 7.5 ft. lb.
The installation of cylinder head side -6 is carried out in the same way as the assembly sequence for side 1-3 with the following change:
- The threaded bolt for guide rail 4-6 on the cylinder head (belt pulley side) -1- is inserted only after the timing chain has been fitted on the camshaft timing gears.
Subsequent work for installing cylinder head
1. Insert three new O-rings at the spark-plug recesses -arrows-, lightly coat with high-pressure grease.
Note: There must be no visible signs of wear on the flat-base tappets and fitting bores of the flat-base tappet housing.
2. Fit flat-base tappet housing with 11 M6 35 Torx screws -1- and tighten screws from the inside out. Tightening Torque: 7.5 ft. lb.
ATTENTION: Interchanged or dirty flat-base tappets.
^ Damage to engine components
^ The components have been run in the fitting bores in the housing, therefore do not interchange them.
^ Pay attention to cleanliness.
3. Coat the flat-base tappets with new engine oil and insert them in their original position into the fitting bores in the flat-base tappet housing. The operating plunger position (inlet side) is pre-set by the dowel pin -arrow-.
4. Install camshaft and set timing.
5. Install cylinder head cover.
6. Fit exhaust manifold with new screws M8 x 26. Position new metal seal with the seam towards the cylinder head. Tighten screws from the inside out. Tightening Torque: 17 ft. lb.