Part 2
WM 100137 Disassembling and assembling engine (continued)Assembling engine - starting with the crankcase
Assembling engine - starting with the crankcase
Caution
Risk of damage due to particles of dirt.
Danger of material damage due to blocked oil bores/oil ducts.
- Absolute cleanliness is essential when working on the engine.
- Lay removed engine parts on a clean base and make sure to cover them.
- Use the cover for dust protection when fitting the engine NR.165 on the engine assembly support.
Information
All O-rings and seals (shaft seals), micro-encapsulated, coated screws or lock nuts must be replaced.
The engine is assembled in reverse order to the disassembly. Components that are not replaced must be cleaned.
Markings on crankcase:
Engine number
Engine number, e.g. 3.8l
Cylinder arrangement
Cylinder arrangement
Information
Replace M6 micro-encapsulated screws and M8 hexagon collar nut for intermediate shaft bearing cap.
1. Fit bearing cover for intermediate shaft with new sealing ring.
2. Install guide rail for cylinder 4-6. Insert guide rail with slot into the crankcase. Fit screw with new O-ring, grease the O-ring with Optimol MP3. - Tightening torque: 10 Nm (7.5 ftlb.)
3. Install tensioning rail for cylinder 4-6. Fit screw with new O-ring, grease the O-ring with Optimol MP3. - Tightening torque: 10 Nm (7.5 ftlb.)
4. Remove auxiliary screw for gear carrier.
5. Fit air/oil separator (swirl pots) and suction pipe. Replace two micro-self-locking M6 x 20 Torx screws and O-rings for the suction tube. - Tightening torque: 10 Nm (7.5 ftlb.)
Components in the oil pan
6. Install oil pan. Apply a bead of sealant, Loctite 5900, to the cleaned and greased oil pan and secure with 13 M6 x 20 Torx screws from the inside out. - Tightening torque: 10 Nm (7.5 ftlb.)
7. Fit oil filter, grease new O-ring with Optimol MP3. - Tightening torque: 25 Nm (19 ftlb.)
8. Fit thermostat with new seal. Tighten four M6 x 20 Torx screws. - Tightening torque: 10 Nm (7.5 ftlb.)
9. Fit tensioning rail for cylinder 1-3. Fit screw with new O-ring, grease the O-ring with Optimol MP3. - Tightening torque: 10 Nm (7.5 ftlb.)
Information
Replace O-rings for the oil pump and sealing rings for coolant guide housing.
10. Install coolant pump. Position pump with the new seal (a single part in conjunction with the seal for the oil pump housing). Position and tighten seven M6 Torx screws (two M6 x 30 screws on the dowel sleeves, five M6 x 25 screws). - Tightening torque: 10 Nm (7.5 ftlb.)
11. Remove centering mandrel for intermediate shaft. Position oil pump with new seal and two new O-rings. Grease the O-rings with Optimol MP3. Pull timing chain 4-6 outward so that the intermediate shaft is centered. Align driver for the oil pump and then push the housing together with the oil pump into the bearing seat. It is advisable to get a second person to assist to make the assembly easier.
Tension timing chain 4-6
12. Coat the thread of two M6 x 70 Torx screws with Loctite 574 and position on oil pump housing. Position the remaining eight M6 x 20 Torx screws, tighten all screws. - Tightening torque: 10 Nm (7.5 ftlb.)
13. Fit coolant connection piece with new seal and two M6 x 20 Torx socket screws. - Tightening torque: 10 Nm (7.5 ftlb.)
14. Fit coolant breather adapter with new seal and six M6 x 20 Torx socket screws. - Tightening torque: 10 Nm (7.5 ftlb.)
15. Fit pulse sender with new, micro-self-locking M6 cheese head bolt. - Tightening torque: 10 Nm (7.5 ftlb.)
16. Fit belt pulley/vibration balancer.
17. Fix timing chains with chain sprockets, e.g. with the old O-rings from the oil suction pumps.
Fixing timing chains
18. Install temperature sensor for coolant (M14 a/f 22). - Tightening torque: 25 Nm (19 ftlb.)+/- 5 Nm (+/- 3.5 ftlb.)
Information
Cylinder-head gaskets are identical parts, lay them down with the TOP identification facing upwards.
19. Fit new cylinder-head gaskets, the TOP marking is legible from above.
20. Fit cylinder heads. Observe tightening sequence and tightening specification of cylinder-head screws. - Initial tightening: 30 Nm (22 ftlb.) loosen all screws, - 2nd initial tightening: 20 Nm (15 ftlb.) - 2 x torque angle (final tightening): 70 degrees
Tightening sequence for cylinder head
21. Tighten external M6 (Torx) cylinder-head screws. - Tightening torque: 13 Nm (9.5 ftlb.)
External cylinder head screwed connection
22. Install guide rail for cylinder 1-3. The slot is positioned in the crankcase, the sealing lip towards the outside. Fit screw with new O-ring, grease the O-ring with Optimol MP3. - Tightening torque: 10 Nm (7.5 ftlb.)
The threaded pin for guide rail 4-6 (belt pulley side) on the cylinder head is inserted only after the timing chain has been fitted on the camshaft wheels.
Information
The O-rings for the spark-plug recesses must be replaced.
23. Insert three new O-rings in the spark-plug recesses, lightly coat with high pressure grease. Fit flat-base tappet housing with 11 M6 x 35 Torx screws and tighten screws from the inside out. - Tightening torque: 10 Nm (7.5 ftlb.)
O-rings for spark-plug recess
Information
Re-insert flat-base tappets in the fitted bores in which they were positioned before the disassembly. The flat-base tappets have been run in in the fitting bores in the housing and therefore may not be switched.
24. Coat bucket tappets with new engine oil and insert in the fitted bores in the bucket tappet housing (operating plunger with dowel pin on the inlet side).
Switchable tappet
25. Install camshafts and adjust controls as for engine type M96/03-3, 6I as of model year 2002.
26. Fit cylinder head cover. Eight new, coated screws -1- must be used for the threaded joints on the camshaft bearing surfaces. For each one, tighten 20 M6 fastening screws according to the tightening sequence. Of each of the sets of 20 screws, only position two screws on the oil suction side (or tandem pump) and only perform the final tightening after fitting the pumps. - Tightening torque: 13 Nm (9.5 ftlb.)
Screws for camshaft bearing surface
Sealant application on cylinder head cover
Sealant application on cylinder head cover
Tightening sequence for cylinder head cover
Tightening sequence for cylinder head cover
27. Install tandem pump and oil suction pump with new, micro-self-locking screws and new O-rings. Fit the line on the tandem pump with two new O-rings. Grease O-rings with Optimol MP3. - Tightening torque: 10 Nm (7.5 ftlb.)
Install engine accessories in the reverse sequence to that in which they were removed. Some additional instructions follow.
Install six spark plugs: - Tightening torque: 30 Nm (22 ftlb.) - Tightening torque: 25 Nm (19 ftlb.)
Six ignition coils: tighten two M6 Torx socket screws for each of them. - Tightening torque: 10 Nm (7.5 ftlb.)
Hall sender: use two new M6 micro-self-locking screws. - Tightening torque: 10 Nm (7.5 ftlb.)+/0.5 Nm (+/-0.5 ftlb.)
Exhaust manifold: use new M8 x 28 hexagon-head bolts. - Tightening torque: 23 Nm (17 ftlb.)
Support for coolant ventilation: replace one M6 x 16 (micro-self-locking) screw. - Tightening torque: 10 Nm (7.5 ftlb.)
Fit oil separator with new O-rings. Screw in M6 x 20 fastening screws on support bracket (3.8 l engine) or crankcase (3.6 l engine). - Tightening torque: 10 Nm (7.5 ftlb.)
Install secondary air pump three M6 x 20 Torx screws on the bracket - Tightening torque: 10 Nm (7.5 ftlb.)
Intake pipe support in the 3.6l: install with four M6 x 35 Torx screws and new seals. - Tightening torque: 10 Nm (7.5 ftlb.)
Intake-air distributor in the 3.6l: install with six M6 x 35 Torx screws and new moulded seals on intake pipe support. - Tightening torque: 10 Nm (7.5 ftlb.)
Intake-air distributor in the 3.8 1: four M6 Torx screws. - Tightening torque: 10 Nm (7.5 ftlb.)
Install generator: tighten M8 hexagon nut for B+ cable to the specified torque. - Tightening torque: 15 Nm (11 ftlb.).
Subsequent work for assembling engine
Subsequent work for assembling engine
1. Fit flywheel.
2. Fit clutch.
or
3. Fit converter housing.
4. Fit drive plate for converter.
5. Mount transmission.
6. Install engine.