Part 1

WM 101651 Partially Disassembling Engine - Sealing Joint




















Preliminary work

Preliminary work for disassembling engine
1. Remove engine.
2. Remove transmission
3. Remove rear silencers and catalytic converters.

Tiptronic transmission:
- Detach torque converter housing.
- Removing drive plate for converter.

Manual transmission:
- Remove clutch.
- Remove dual-mass flywheel.

Partially disassembling engine

Partially disassembling engine - cylinder bank 4-6

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.

Warning: Coolant is corrosive and hazardous to health.
^ Risk of skin and eye irritation.

-> Wear protective gloves and goggles.
-> If you come into contact with coolant, wash off immediately with plenty of warm water.

Warning: Pentosin is hazardous to health
^ Danger of material damage and injury

-> Wear protective gloves and goggles.
-> If the eyes or skin come into contact with the fluid, wash immediately with water.
-> Collect emerging Pentosin. Clean hoses which come into contact with Pentosin thoroughly.
-> Use caps to protect the wiring against soiling and damage.

1. Engine support 9589 must be secured to the crankcase using special tool mounting elements 9590. Refit engine with support on the engine assembly support.





2. Drain engine oil. Unscrew the oil drain plug (hexagon socket, a/f 8).





3. Remove engine carrier. Unscrew four M10 collar nuts -1- and one M6 x 20 Torx screw -2-.





4. Unscrew three M8 x 12 fastening screws on the pulley for the power-steering pump.
4.1. Hold pulley -2- with arm bracket Nr.193 -1-. Loosen and remove screws -3-. Remove pulley.





5. Unclip vacuum lines -1- at the intake distributor, cylinder bank 1 - 3, and disconnect plug connections.
5.1. Disconnect cable plug -2- from cycle valve.





6. Unplug crankcase vent line from pre-separator, cylinder 4-6, and from oil separator.





7. Remove heat shield -1- for ignition coils, side 4-6, unscrew two M6 x 16 fastening screws.





8. Disconnect electric plug connections (engine wire harness) on engine and unclip wire harness on the fuel collection pipes.





^ Three fuel injector plugs per cylinder bank -1-.
^ Three ignition coil plugs per cylinder bank -2-.
^ Two connectors for camshaft control hydraulic valves and two for valve lift adjustment hydraulic valves -3-.
^ Connector for coolant temperature sensor, two connectors for oil pressure sensor on cylinder head cover 4-6 -4-.
^ Two hall sender connectors.
^ Connector for speed sender.
^ Ground cable for front face of cylinder 4-6 (one M6 x 12 Torx screw).
^ Connector for engine compartment temperature sensor (intake distributor 4-6).
9. Unclip fuel ring pipe on the engine eyelet and unscrew two M6 x 16 Torx screws, remove engine eyelet.
10. Detach holder for the throttle body on the power-steering pump. To do so, unscrew an M6 hexagon nut.
10.1. Unplug cable plug for potentiometer and line for positive crankcase ventilation.
11. Undo holder for servo supply tank on intake distributor 4-6.

Caution: Mixing fluids
^ Risk of damage to components

-> Close off all openings immediately after exposing them (with adhesive tape, suitable stoppers).

12. Only for 3.6-liter engine: Remove intake-air distributor together with the intake pipe support.
12.1. To do this, unscrew four M6 x 35 screws -arrows-, unscrew one M6 x 12 screw for ground strap on cylinder bank 4 - 6.
12.2. Pull off one vacuum line.
12.3. It is advisable to get a second person to assist in removing the entire intake manifold.
12.4. Lift the entire intake manifold up and off, seal intake openings on cylinder head (e.g. with adhesive tape).





13. Only for 3.8-liter engine: Unscrew the four M6 x 35 Torx screws -1-. Completely remove the intake distributor. Seal intake openings on cylinder head (e.g. with adhesive tape).





14. Remove pulley from power-steering pump. Unscrew three fastening screws and remove pulley.
15. Remove generator.
15.1. Loosen the fastening screw on the deflection roller -1- and unscrew approx. three turns.
15.2. Using an aluminum mandrel, tap lightly on the screw head to loosen the guide bush in the generator swivel arm. Unscrew the screw and remove with the deflection roller.
15.3. Then unscrew the second screw -2-.





16. Lift the generator out of the bracket and disconnect the two electric connecting lines -arrows-.





17. Remove holder for the coolant vent line. Unscrew one M6 x 16 (micro-self-locking) Torx screw, remove holder, replace screw.
18. Unplug all vent lines on the oil mist separator -arrows-.





19. Unscrew the two M6 x 20 Torx screws -arrows- on the 3.8-liter oil mist separator holder and pull off separator. The screws tighten the secondary air line on cylinder head 4-6 at the same time.
19.1. Replace O-rings and seal for the secondary-air line before joining the lines again.





20. The oil mist separator in the 3.6-liter engine is secured on cylinder bank 1-3 using two M6 cheese head bolts in the same way as for the 996 unit.





21. Unscrew one fastening screw for the wire harness guide on the bracket for the secondary-air pump -1-and unclip the guide -2- at the bracket -arrow-.





22. Remove secondary-air line. Loosen and unscrew one union nut on the shut-off valve.
22.1. Unscrew two M6 Torx screws on the crankcase side, remove line (on the 3.8-liter the screws were already removed by removing the oil mist separator).
22.2. Replace seal when assembling.
23. Release the wire harness on the holder before the heat exchanger. Then unscrew the plastic holder.





24. Disconnect the wire harness on the center of the engine (connections at starter) -arrow- and unclip at the heat exchanger -1-.
24.1. Unplug cable plug for knock sensors -2- and oil level sensor.
24.2. Then completely remove the engine wire harness.





25. Remove the oil filler pipe -1-. Unscrew two M6 x 16 (micro-self-locking) Torx screws -arrows- and pull out oil filler pipe. Close off or mask off opening immediately.
25.1. Check O-ring and replace if necessary.





26. Remove oil/water heat exchanger. Unscrew the four inner M6 x 16 Torx screws, take off heat exchanger. Close off openings immediately.
26.1. Replace O-rings during installation.
27. Remove hydraulic pump with servo line and supply tank.
27.1. Disconnect servo line (a/f 16) -1-. Counter at the large hexagon when doing this (a/f 27).
27.2. Unscrew four Torx screws (three M8 x 30 at the front -arrows-, one M8 x 12 at the back).
27.3. Take the power-steering pump with line and supply tank out of the bracket.





28. Remove bracket for power-steering pump. Unscrew four M8 x 35 Torx screws -1- and remove bracket -2-





29. Remove canister for additional volumes of positive crankcase ventilation at cylinder head 4-6. Unscrew two M6 x 25 Torx screws and remove canister.
29.1. Use new O-rings when installing.
30. Remove the holder for the main silencer on side 4-6.
30.1. Unscrew two M8 x 30 Torx screws on the intake side and two M8 x 25 on the exhaust side and take off holder.





31. Remove ignition coils -1-. Unscrew M6 x 25 Torx screws, pull off ignition coils.
31.1. Remove holder and sealing cap for camshaft control hydraulic valves -2-. Unscrew two M6 x 20 Torx screws each, take off holder and sealing cap.





32. Remove six spark plugs. Use only approved tool spark plug socket wrench 14 from Snap-On (in case ceramic body breaks).
33. Pull off hydraulic valves for camshaft control and valve lift adjustment. The special tool relay puller 9235 can be used to do this.
33.1. Pull the oil strainer for the camshaft control valve -1- out of the valve bore using a magnet, replace the oil strainer.





34. Remove exhaust manifold, side 4-6. Unscrew six M8 x 28 screws, remove manifold and seal.
35. Remove coolant pipe for heater on side 4-6. Unscrew three M6 x 12 Torx screws and remove coolant pipe.
36. Remove oil pressure sender on cylinder head cover 4-6 (a/f 19).
37. Remove the holder for the air conditioning compressor. Unscrew two M8 fastening screws, and remove bracket.
38. Remove hall sender. Unscrew one M6 x 16 cheese head bolt (hexagon socket a/f 5, micro-self-locking) and pull off hall sender, replace bolts.
39. Remove plastic lids on the cylinder heads.
39.1. Replace lids when assembling.
40. Remove oil extraction pump for cylinders 1-3. Unscrew four M6 x 20 Torx screws (coated), carefully pull the oil suction pump out of the fitting bore.
40.1. Replace O-rings and screws when assembling.





41. Remove tandem pump on cylinder bank 4-6. Unscrew four M6 x 30 Torx screws (coated) -1-, pull vacuum line -2- out of the joining socket on the pump, take out the pump.
41.1. Replace O-rings and screws when assembling.
42. Move engine at the pulley of the crankshaft clockwise to the overlapping TDC of cylinder bank 4-6.
42.1. To do this, turn the engine clockwise until the TDC mark on the pulley or the vibration balancer is aligned with the marking on the crankcase. To check cylinder 4-6, insert the special tool adjusting gauge 9686 into the camshaft slots.
42.2. If the adjusting gauge does not fit, turn engine a further 360° and reinsert the gauge.








Note: The central screws of the camshaft adjustment elements must be undone before removing the cylinder head cover.

43. The central screws of the camshaft controller must be loosened before removing the cylinder head covers. To do this, place special tool retaining tool 9685 on the large hexagon of the central screw and cylinder head cover and loosen the screws.
43.1. If the tool cannot be positioned, the engine must slowly be turned further until the tool can be supported on the cover -> Retaining tool 9685.





44. Remove cylinder head cover.
45. Remove all chain tensioners and replace aluminum sealing rings during installation.
46. Remove upper M6 screw (hexagon socket a/f 5) for guide rail of cylinders 4-6.





47. Remove camshaft side 4-6.

Caution: Interchanged or dirty bucket tappets.
^ Damage to engine components.

-> The components have been run in the fitting bores in the housing, therefore do not interchange them.
-> Absolute cleanliness is essential.

48. Remove bucket and switching tappets. Use a strong magnet to pull the components out of the bucket tappet housing. To avoid confusing the individual tappets, lay them on a labelled, clean surface (see example) and cover.
48.1. Check tappets for visible damage (signs of seizing for example).





49. Remove bucket tappet housing. Unscrew eleven M6 x 35 Torx screws per housing, a 1/4-inch E10 socket is required for this.
49.1. Take bucket tappet housing out of cylinder head.
49.2. The O-rings for the spark-plug recesses must always be replaced during installation.
50. Unscrew four M6 x 30 Torx screws -items 1 - 4- on cylinder head 4-6.





51. Remove cylinder head 4-6.
51.1. Loosen and unscrew twelve M10 x 230 Torx screws from the outside to the inside.
51.2. Lift the cylinder head and seal off the crankcase.

Note:
^ Mark pistons in installation position before removal. Combustion residues (carbon deposits) can be removed with a brass brush.
^ Hard to remove residues can be removed in the ultrasound bath following disassembly.

52. Remove all carbon deposits and other residues on pistons 4-6 with a brass brush, which will make the engraved markings -arrow points to flywheel side- visible. In addition, number the pistons in installation position before removing them.





53. Unscrew M27 aluminum screw plug for the assembly bore (piston pin).
54. Remove coolant guide housing and oil pump. Unscrew an M8 x 60 Torx screw -1-.
54.1. Unscrew ten M6 Torx screws, two of which are M6 x 70 -2- and eight are M6 x 20 -3-. Carefully lift off housing with seal (you may need to press gently with an assembly lever).
54.2. Remove the drive belt guide in Tiptronic vehicles -4-.
54.3. Pull out the driver for the oil pump.





55. Remove lower M6 guide and tensioning rail screws (hexagon socket a/f 5) on side 4-6, remove the guide and tensioning rail from the chain slot.
56. Remove oil filter with special tool release key 9204.
57. Unscrew 13 M6 x 20 Torx screws on the oil pan cover. Tap cover gently on the sides using a plastic hammer, then carefully lift it at the leverage bar -see figure- using a plastic-coated mounting lever and remove the oil pan.