Part 2

WM 1001Z2 Assembling V8 4.8-liter DFI engine (continued)

19. Turn upper part of crankcase and oil cylinder liners.

Information:
The corresponding connecting rod bearing shells must be selected according to the marking on the crankshaft transmission flange (4-digit) and inserted into the connecting rod.
When removing the pistons with connecting rods, the pistons should be marked with a water resistant marker on both the piston and connecting rod according to cylinder and cylinder bank.
The removed pistons and connecting rods must be cleaned carefully so as not to remove the markings.
The connecting rod code is installed to the exhaust side as standard. The direction of travel arrow on the DFI piston is always on the same side as the connecting rod code -A-. The pistons are assigned to the cylinder bank (1 to 4 and 5 to 8), i.e. because of the DFI combustion chamber recess there are two different pistons for the left and right cylinder bank.
When installing the piston in the crankcase, the direction of travel arrow must point in the direction of travel when installed. It is always on the same side as the connecting rod code. The combustion chamber recess on the piston is always on the intake side. Note the assignment of the pistons to the cylinder bank.

Connecting rod code and direction of travel arrow

Naturally aspirated engines and turbo engines have different pistons.

The code on the connecting rod big end and connecting rod cap must always be on the same side and at the exhaust side. -A-

Note: Select the correct piston for the correct cylinder bank. Install with connecting rod code on the exhaust side with the direction of travel arrow on the piston.

Connecting rod code "A"

20. Tension piston using commercially available piston ring restraining strap (e.g. Universal piston ring restraining strap Nr.55) and press piston into cylinder. When doing so, make sure that the direction of travel arrow on the piston crown is pointing in the direction of travel and the connecting rod code has been fitted facing the exhaust side. Push the pistons in until the connecting rod bearing is lying on the con rod journal of the crankshaft. Once all the pistons with connecting rod have been pushed in, fit connecting rod cap evenly and synchronously with the correct bearing shell. Fit with new connecting rod bolt to the prescribed tightening torque.

Piston, connecting rod

1 - Oil piston ring set with engine oil; TOP marking facing upwards; oil scraper ring down
2 - Piston; different on naturally aspirated and turbo engines; combustion chamber recess facing center of engine; left and right different; direction of travel arrow in direction of travel
3 - Piston-pin circlip (positioned at 6 o'clock or 11 o'clock)
4 - Piston pin; oil
5 - Connecting rod
6 - Connecting rod bolt; replace as it must be tightened in the plastic area; oil bolt - Tightening torque: 8 Nm (6 ftlb.)+2 Nm (+1.5 ftlb.) - Tightening torque: 20 Nm (15 ftlb.) - Tightening torque: 40 Nm (30 ftlb.) - Torque angle: 90°
7 - Connecting rod bearing shells; oil with engine oil

Tensioning pistons

Piston assembly

Pressing in pistons

21. Remove crankshaft holding bridge. Applying Drei Bond 2210 (000.043.204.58 status 04/07) sealant to lower part of crankcase as shown in the illustration. Insert sealing ring -3- into the upper part of the crankcase and position the lower part of the crankcase onto the upper part of the crankcase. Insert all the fastening screws, fit to the prescribed tightening torque within 5 minutes and wipe off excess sealant.

Sealant application

1 - Wipe off sealant residues after fitting
A - Direction of travel

22. Screw down M11 and M10 bearing screws to the prescribed torques. -5 and 6-

Tightening sequence for thrust bearing screws

1 to 20 - Tightening sequence for M11 and M10 screws - Observe different torques!
A - Direction of travel

Lower part of crankcase

1 - Lower part of crankcase
2 - Straight pin, 6 x 18
3 - O-ring
4 - Applying sealant; Drei Bond 2210 (000.043.204.58 status 04/07)
5 - Thrust-bearing screw M11; tighten screws within 5 minutes; observe tightening sequence. - Tightening sequence for thrust bearing screws - Initial tightening: 30 Nm (22 ftlb.) - Torque angle: 90°C
6 - M10 thrust bearing screw; tighten screws within 5 minutes; observe tightening sequence. - Initial tightening: 22 Nm (16 ftlb.) - Torque angle: 60°C
7 - Screw, M8 x 70; (cross bolt connection); observe tightening sequence - Tightening torque: 23 Nm (17 ftlb.)
8 - Screw, M8 x 35 - Tightening torque: 23 Nm (17 ftlb.)
9 - Screw, M8 x 50 - Tightening torque: 23 Nm (17 ftlb.)
10 - Dowel sleeve
A - Direction of travel

23. Fit cross bolt connection.

Tightening sequence for securing lower part of crankcase to upper part of crankcase (cross bolt connection)

24. Fit M8 screws on the side -8 and 9-. Remove emerging sealant.
25. Punch in or imprint the engine number if necessary (when replacing engine).
26. Move oil plate with all the seals into installation position and secure to the lower part of the crankcase. - Tightening torque: 10 Nm (7.5 ftlb.).

Oil guide (oil plate)

27. Grease sealing ring between the oil plate transfer pipe and oil pump sparingly with Kluber Syntheso GLEP 1 and fit oil pump. Secure the oil pump.

Oil pump on turbo engine M48/51 with oil extraction stage

1 - Oil pump with extraction stage
2 - Screw, M8 x 22; replace; 1st turn - Initial tightening: 20 Nm (15 ftlb.); final tightening (torque angle) - Torque angle: 90°
3 - Oil pump sprocket
4 - Cap screw, M36 x 1.5 x 12 - Tightening torque: 40 Nm (30 ftlb.)
5 - Solenoid valve
6 - O-ring (grease before fitting)
7 - Dowel sleeve
8 - Screw, M6 x 45 - Tightening torque: 13 Nm (9.5 ftlb.)
9 - Sprocket cover
10 - Screw, M6 x 16 - Tightening torque: 10 Nm (7.5 ftlb.)
11 - Drive chain
12 - Connection for intake manifold joining socket
A - Direction of travel

28. Position oil pump sprocket with drive chain with respect to crankshaft chain pinion. Counter oil pump sprocket at the oil pump using a screwdriver and fit new screw. 1st turn - Initial tightening: 20 Nm (15 ftlb.); final tightening (torque angle) - Torque angle: 90°

Oil pump chain

Countering oil pump pinion

29. Fit cover plate for oil pump drive using three screws. - Tightening torque: 10 Nm (7.5 ftlb.)
30. Turn engine and clean sealing faces. Blow out bores of cylinder head screws. Position both cylinder head seals. Part number/marking facing upward. When doing so, make sure that the cylinder head gasket is positioned on the dowel sleeves.
31. Unscrew front camshaft mounting saddles (lower parts) of the cylinder heads (if you have not already done so), as the bores in the cylinder head screws are covered. see illustration, item 8

Cylinder head 1 to 4

1 - Cylinder head 1 to 4
2 - Cylinder head gasket 1 to 4
3 - Screw, M8 - Tightening torque: 23 Nm (17 ftlb.)
4 - Lid
5 - Stopper
6 - Stopper
7 - Restrictor for valve lift control - Tightening torque: 1.5 Nm (1.0 ftlb.)
8 - Cylinder-head screws
9 - Spark plug; when reinstalled - Tightening torque: 25 Nm (19 ftlb.)+3 Nm (+2 ftlb.); if fitting new spark plugs - Tightening torque: 30 Nm (22 ftlb.)+3 Nm (+2 ftlb.)

Tightening sequence for cylinder head

Bolts 1 to 10
- 1st initial tightening - Tightening torque: 30 Nm (22 ftlb.); 2nd initial tightening - Tightening torque: 50 Nm (37 ftlb.); loosen by 2 turns - Torque angle: 720°; 1st turn - Tightening torque: 30 Nm (22 ftlb.); 2nd turn - Tightening torque: 30 Nm (22 ftlb.); 3rd turn and final tightening (torque angle) - Torque angle: 110°

33. Fit front M8 screw of cylinder head 1 to 4. - Tightening torque: 23 Nm (17 ftlb.)
34. Make sure that the intake openings have been protected using adhesive tape or something similar to prevent them from becoming dirty.
35. Insert front camshaft mounting saddles (lower parts) of cylinder heads. Item 8

Camshafts, cylinder bank 1 to 4

1 - Camshaft (outlet)
2 - Camshaft (intake)
3 - Hydraulic valve for variable valve lift control
4 - Screw, M5 x 12 - Tightening torque: 6 Nm (4.5 ftlb.)
5 - Switching tappet (oil with engine oil)
6 - Bucket tappet (oil with engine oil)
7 - Stopper
8 - Mounting saddle 1 to 4
9 - Stopper
10 - Bearing locations (oil with engine oil)
A - Direction of travel

36. Coat camshaft bearings with normal multipurpose grease or engine oil.
37. Insert bucket tappets into the cylinder head if necessary (bucket tappets for intake and outlet side have different diameters). The bucket tappets have a twist lock that fits into a guide groove in the cylinder head. Fit used bucket tappets at the same position.
38. Position vibration balancer with screw tightened by hand. Turn crankshaft to just before cylinder 1 TDC (prevents the valves from sitting on the piston when directly at TDC). Item 2

Staking bore 45° before TDC

Information:
A data matrix coding is shown on the staking dihedron of the camshafts. This is a square black/white dotted marking used for electronic identification purposes during the production process. This marking can be used as an aid when inserting the camshafts into the cylinder head. All four camshafts press against the valves the least when the data matrix coding is facing upwards during installation.

39. Insert camshafts so that the minimum amount of pressure is exerted on the valve springs and coat bearing locations with normal multipurpose grease or engine oil. Position housing correctly and screw down. The housings are numbered and marked with E (intake) or A (outlet). Fit camshaft housings evenly and gradually, and slowly approach the tightening torque. The camshafts must not be preloaded or tilted. Outlet camshafts and intake camshafts (also bank specific) cannot be confused because of the bearing locations and length.

Camshaft identification on V8 turbo engine M48/51

A - Cylinders 1 to 4
B - Cylinders 5 to 8
1 - Outlet camshaft identification (green)
2 - Intake camshaft identification (blue)
3 - Intake camshaft identification (blue)
4 - Outlet camshaft identification (green

Camshaft housing identification

- All markings can be read from the exhaust side/main diagram applies symmetrically for both cylinder heads
1 - Matching number for cylinder head/intake camshaft housing, cylinder 1 (E1)
2 - Matching number for cylinder head/intake camshaft housing, cylinder 2 (E2)
3 - Matching number for cylinder head/intake camshaft housing, cylinder 3 (E3)
4 - Matching number for cylinder head/intake camshaft housing, cylinder 4 (E4)
5 - Matching number for cylinder head/outlet camshaft housing, cylinder 1 (A1)
6 - Matching number for cylinder head/outlet camshaft housing, cylinder 2 (A2)
7 - Matching number for cylinder head/outlet camshaft housing, cylinder 3 (A3)
8 - Matching number for cylinder head/outlet camshaft housing, cylinder 4 (A4)
Pfeil - Direction of travel

Camshaft mount, cylinders 5 to 8

1 - Dowel sleeves
2 - Housing (intake)
3 - Screw, M6 x 70 - Tightening torque: 13 Nm (9.5 ftlb.)
4 - Housing
5 - Screw, M6 x 35 - Tightening torque: 13 Nm (9.5 ftlb.)
6 - Housing (outlet)
7 - Bearing surfaces (oil with engine oil)
A - Direction of travel

40. Move both hydraulic valves for camshaft control into installation position and fit them. Item 5

Camshaft control

1 - Screw, M12 Tighten completely after setting timing.
2 - Hexagon sleeve
3 - Camshaft controller
4 - Washer (reusable); replace if disassembled completely
5 - Camshaft control hydraulic valve
6 - Screw, M5 x 12 - Tightening torque: 6 Nm (4.5 ftlb.)
A - Direction of travel

41. Insert oil vent line at the firewall side of cylinder 5 and screw it on. Grease sealing ring sparingly with Kluber Syntheso GLEP 1.

Vent line

1 - Vent line to cylinder head/crankcase/oil pump
2 - O-ring
3 - Screw, M6 x 12 - Tightening torque: 10 Nm (7.5 ftlb.)
4 - Check valve
A - Direction of travel

42. Fit threaded peg for tensioning and guide rails. Items 1 and 2

Timing chain and chain guide

1 - Threaded peg - Tightening torque: 35 Nm (26 ftlb.)
2 - Threaded peg - Tightening torque: 20 Nm (15 ftlb.)
3 - Guide rail
4 - Tensioning rail
5 - Chain tensioner with sealing ring
6 - Pin (for locking the oil-pump tensioning rail)
A - Direction of travel

43. Fit guide rail with oil pump chain tensioning rail and pull locking pin (tensioning rail will be released).
44. Fit "U" shaped deflection rail item 4.

Timing chain and sprockets

1 - Double-chain camshaft drive
2 - Camshaft sprocket
3 - Screw, M12 x 140 Tighten completely after setting timing.
4 - Deflector rail
5 - Screw, M8 x 35 - Tightening torque: 32 Nm (24 ftlb.)
6 - Camshaft-to-camshaft guide pad
A - Direction of travel

45. Fit tensioning rail and let it hang.
46. Fit both small guide rail pieces between the camshaft controller and sprocket.
47. Loosely fit camshaft controller and sprockets using screws (do not forget new diamond washer under the camshaft controllers).
48. Position timing chain and guide correctly over guide and tensioning rails.
49. Fill Loctite 5900 (000.043.204.35 status 04/07) first into the opening of the seal for the timing-case cover. Apply sealant as shown in the illustrations. Install the timing-case cover within 5 minutes.

Timing-case cover seals

1 - Timing-case cover
2 - Timing-case cover seal, outer right (fill openings with sealant, see 6)
3 - Timing-case cover seal, inner
4 - Timing-case cover seal, rib
5 - Timing-case cover seal, outer left (fill openings with sealant, see 6)
6 - Applying sealant to timing chain housing; Loctite 5900 (000.043.204.35 status 04/07)
A - Direction of travel

Applying sealant (fill openings in metal seal with sealant)

50. Move timing case cover with pre fitted metal seals into installation position (carefully insert oil vent line, grease sealing ring sparingly with Kluber Syntheso GLEP 1 if necessary). When doing so, press the tensioning rail away from the sprocket at the timing chain using a screwdriver (second worker required). Position timing case cover.
51. Fit the timing case cover using four to six screws. Align timing case cover with the edge of the lower part of the crankcase (realign using plastic hammer if necessary). Fit remaining screws. Check projection again with respect to the lower part of the crankcase and realign if necessary. The timing case cover can be adjusted using a dial gauge, steel rule or by touch (projection of timing case cover with respect to the lower part of the crankcase). It should not be possible to feel or measure any projection on either side of the timing case cover.

Example: Adjusting timing case cover using a dial gauge

52. Insert the dial gauge into the universal gauge holder and position it so that the dial gauge has a preload of about 1 mm.

Adjusting preload

53. Set dial gauge scale to 0. To do this, place the dial gauge holder on a completely flat surface (e.g. crankcase) and turn the dial gauge scale until the pointer is at 0.

Setting dial gauge scale to zero

54. Measure offset. In order to do this, push with the holder starting from the lower part of the crankcase towards the timing case cover (the foot of the dial gauge holder is not located on the same component as the dial gauge probe) and measure the offset. The timing case cover must not be set back any more than 0.1 mm. A projection is not permissible.

Measuring offset

55. Align the timing case covers by tapping lightly with a rubber hammer.

Aligning chain case lid

56. Then check the position of the timing case cover again with the dial gauge.

Checking

57. Fit timing case cover according to specifications. When doing so, do not forget any of the sheetmetal holders under the screws.