Installing Chain Case Lid
Installing chain case lidInformation
Component overview
Installing chain case lid
ATTENTION Leaks due to components being at too low a temperature or at different temperatures!
^ If components that are cold or at different temperatures are sealed together by the application of sealant, adhesion problems and leaks can arise due to the build-up of condensation water or component distortion.
^ Components must have reached at least 17°C throughout.
^ Components must not be too hot (distortion).
^ Spare parts that are stored in the cold or heat (strong sunlight), must be brought to room temperature or the same temperature as other parts before installation.
Note: Acetone can be used to clean the sealing faces. Ventilate this for 5 minutes before applying more sealant.
1. Clean and degrease the sealing faces of the engine and housing lid.
2. Attach the four seals -1, 2, 3 and 4- to the chain case lid.
3. Apply a bead of liquid sealant 000.043.300.39 Loctite 5970 (status 11/2005, for details of currently used sealant, see Parts Catalogue) to the contact points of the camshaft housing/cylinder head, cylinder head/crankcase and crankcase upper section/crankcase lower section. The bead of sealant should protrude about 20 mm over the contact points.
Note: In the case of the M48/50 (turbo) engine, sealant must also be applied to the metal seal in the chain tensioner area.
4. Screw down all fastening screws by hand. At this stage, the screw heads should not be all the way down.
Note:
^ The chain case lid must be aligned using a dial gauge or steel gauge.
^ The chain case lid must not project over the lower section of the crankcase.
^ It must not go below (-dimension A-)1/10 mm (-dimension A < 1/10 mm-).
5. Push the chain case lid upwards slightly and tighten the fastening screws -7, 8, 9 and 10- (about 1 - 2 Nm (0.5 - 1.5 ft-lb.) in such a way that the lid is slightly jammed. Then align the lid.
Aligning the chain case lid with a dial gauge
ATTENTION Danger of leaks!
^ If the chain case lid is not aligned properly, this component or the oil pan may start to leak during operation.
^ The chain case lid must not project over the crankcase.
^ It cannot go under 0.1 mm (dimension A = 0.1 mm).
1. Insert the dial gauge into the universal gauge holder and position it in such a way that the dial gauge has a preload of about 1 mm.
2. Set dial gauge scale to 0. To do this, place the dial gauge holder on a completely flat surface (e.g. crankcase flange) and turn the dial gauge scale until the pointer is at 0.
3. Measure the offset. To do this, push with the holder starting from the lower section of the crankcase towards the chain case lid (the foot of the dial gauge holder is not located on the same component as the dial gauge probe) and measure the offset. The chain case lid must not be set back any more than 0.1 mm. It must not project out.
4. Align the chain case lid by tapping lightly with a rubber hammer.
5. Once the chain case lid has been aligned, tighten two fastening screws on the left and right of the chain case lid base to 10 Nm (7.5 ft-lb.). Then, check the position of the chain case lid again using the dial gauge.
6. Tighten the remaining fastening screws to the appropriate torque in the sequence shown.
Note: See figure! Tightening sequence
^ The quality of the exterior fastening screws must be 10.9.
^ If the quality is 8.8, the screws must be replaced.
^ Tighten screws 1 to 4 (M6/8.8) to 10 Nm (7.5 ft-lb.).
^ Tighten screws 5 to 6 (M8/8.8) to 23 Nm (17 ft-lb.).
^ Tighten screws 7 to 32 (M6/10.9) to 13 Nm (9.5 ft-lb.).
^ Then check all screws again (second time round).
Subsequent work
1. Install oil pan.
2. Install engine carrier.
3. Fit front radial shaft seal.
4. Fit crankshaft pulley. Fastening screw tightening torque: 250 Nm (185 ft-lb.) + 90° torque angle.
5. Install bracket for oil-water heat exchanger.
6. Fit deflection roller of cylinder row 1 - 4. Tightening torque: 32 (24 ft-lb.) Nm Then clip on cap.
7. Tighten coolant pump pulley.
8. Install belt tensioner. Install holder with tensioning element. Tighten the top fastening screw Tightening torque: 33 (24 ft-lb.) Nm. Tighten the bottom fastening screw Tightening torque: 32 (24 ft-lb.) Nm.
9. Fit and tension the drive belt.
10. Install chain tensioner with new sealing ring.
11. Install oil dipstick.
12. Check timing and adjust if necessary.
13. Install cover for camshaft housing (valve cover).
14. Install engine.