Part 1
Disassembling the engine
Information
Tools and materials
Overview of special tools
Special tools for engine disassembly
1 - Retaining device 9778 with piston receiving element with a diameter of 97 mm.
2 - Piston receiving element 9778/1, diameter: 102 mm.
3 - Funnel 9784 or funnel 9784/2 for piston assembly, diameter: 97 mm or 102 mm.
4 - Piston assembly aid 9787, diameter: 97 mm or piston assembly aid 9787/1, diameter: 102 mm.
5 - Handle for assembly aid 9598.
6 - Disassembly tool 9764 for piston-pin circlips.
7 - Disassembly tool 9777 and assembly tool for piston pins.
8 - Assembly tool 9776 for piston-pin circlips.
9 - Centering mandrel 9782 for connecting rods and pistons.
10 - Assembly aid 9783 for pressing out pistons (cylinders 1-3) and connecting rods with pistons (cylinders 4-6).
not shown - Rubber sleeves, assembly aid 9795 for protecting cylinder linings (assembly on connecting rods for cylinders 1-3).
Preliminary work
Notice
Dirt and contamination
^ Risk of damage to units or components
- Protect components from dirt and contamination.
- Clean or replace dirty components.
Information
^ All engine repairs must be carried out using only the specified tools.
^ Only these tools have been tested and approved.
Information
^ Photos taken with a digital camera are helpful for dealing with complicated line routing.
1. Remove the engine.
2. Remove the transmission.
3. Remove the flywheel.
4. Mount the engine on the engine assembly support.
5. Remove front muffler.
6. Remove rear muffler.
7. Remove engine carrier.
Engine carrier and holder for front muffler
8. Remove exhaust manifold with catalytic converter.
9. Drain engine oil.
9.1. Unscrew drain plug and collect emerging oil.
9.2. Then screw in drain plug with a new sealing ring and tighten to the specified torque.
- Tightening torque: 50 Nm (37 ftlb.)
10. Loosen three external Torx(R) screws (E10, M8 x 12) on the hydraulic pump pulley (do not unscrew fully).
11. Remove the drive belt.
11.1. Unscrew screws for hydraulic pump pulley and remove the pulley.
12. Disconnect cable plugs -1- and -3- on the intake-air distributor on cylinder bank 1-3. Unscrew one external Torx(R) screw (E10, M6 x 12) -2- used to secure the cable duct.
Cable plugs on intake-air distributor 1-3
1 - Cable plug on engine compartment temperature sensor
2 - Cable duct mounting on cylinder bank 1-3
3 - Cable plug on control valve for tank ventilation
12.1. 3.8-liter engine only: Pull off cable plug and vacuum line on control valve for tuning flap.
Control valve for tuning flap
1 - Cable plug on control valve for tuning flap on the resonance tube.
2 - Pull off line on control valve.
13. Disconnect positive crankcase ventilation line on the resonance tube -1- and unclip it at the intake-air distributor -arrows-. Turn the line towards the rear.
Positive crankcase ventilation line on cylinder bank 4-6
13.1. Unscrew one external Torx(R) screw (E10, M6 x 12) -2- used to secure the cable duct to the intake-air distributor.
14. Loosen holder at the oil-fill pipe. To do this, unscrew three external Torx(R) screws (E10, M6 x 12) -2-.
Oil-fill pipe holder and positive crankcase ventilation line
14.1. Unclip positive crankcase ventilation line -3- at the oil-fill pipe.
15. Completely remove intake-air distributor.
15.1. Unscrew six external Torx(R) screws (E10, M6 x 35).
15.2. Completely remove the intake-air distributor and resonance tube.
15.3. Clean sealing faces and close off ducts with adhesive tape or stoppers.
15.4. Replace molded seals.
16. Remove oil filler neck -1-.
16.1. Unscrew two external Torx(R) screws (E10, M6 x 20) -2- and pull the connection piece out of the crankcase.
Oil filler neck
16.2. Close off opening with adhesive tape or a stopper.
16.3. Replace O-ring.
17. Remove the generator.
17.1. Pull off cable plug and unscrew M8 hexagon nut on the B+ line. Remove B+ line.
17.2. Loosen external Torx(R) screws (E12, M8) by two to three turns -1- and fit screw insert (E12) with short extension on the screw head. Loosen threaded sleeves in the unit carrier by tapping gently with a plastic hammer.
Loosening fastening screws for generator
17.3. Unscrew the right-hand screw, leave the left-hand screw in place and take out the generator.
18. Remove upper heat shields -1- for ignition coils.
18.1. Unscrew two external Torx(R) screws (E10, M6 x 12) -2- on each and remove the heat shields.
Upper part of heat shield
19. Unplug several cable plugs and disconnect ground straps for ignition coils.
Cable plugs on cylinder head cover
1 - Connectors for ignition coils
2 - Internal Torx(R) screws (T40) securing ground connection for ignition coils
3 - Hall sender
4 - Solenoid hydraulic valve for valve lift adjustment
20. Remove holder for rear muffler -1-.
20.1. Unscrew four external Torx(R) screws (E12, M8 x 20) -2- and remove holder.
Holder for rear muffler
21. Disconnect B+ line -1- and control line for solenoid switch (terminal 50) -2- at the starter.
Screwing off fastening nuts for cable shoe on the starter
22. Remove positive crankcase ventilation line -1- (air conditioning compressor remains in the vehicle when you remove the engine).
22.1. Open rapid-action couplings by pressing the locking ring -3- and unclip line from the holder -arrow-.
22.2. Replace O-rings on the connection point to the bracket for the oil/water heat exchanger.
Positive crankcase ventilation line
23. Remove hydraulic pump -1- together with the pressure line -2- and return line -3-.
Hydraulic pump and lines
24. Remove housing cover for coolant regulator -1- and coolant intake tube -5- (from the coolant reservoir).
24.1. Unscrew one external Torx(R) screw (E10) M6 x 40 -2-, three M6 x 50 screws -3- and take off the cover and thermostat.
24.2. Unscrew two external Torx(R) screws (E10, M6 x 12) -4- and pull off the intake tube. Replace O-rings.
Intake tube and coolant regulator housing
25. Remove oil separator -1-.
Oil separator
25.1. Unscrew two external Torx(R) screws (E10, M6 x 25) -2- and pull off the oil separator. Replace O-rings.
26. Remove coolant pipe with coolant hose and connection piece (Henn coupling).
26.1. Unscrew three external Torx(R) screws (E12, M8 x 70) -2- on the unit carrier.
Unit carrier
26.2. Unscrew two external Torx(R) screws (E10, M6 x 12) -2- and remove the coolant pipe and connection piece -1-.
Coolant pipe with hose and connection piece
27. Remove the coolant distributor and coolant hoses (on the oil/water heat exchanger).
27.1. Open two spring band clamps -1- and pull the hoses -2- off the oil/water heat exchanger.
Coolant hoses on heat exchanger
27.2. Unscrew two external Torx(R) screws (E10, M6 x 25) -2- and pull up the distributor -1-.
Coolant distributor
Coolant distributor -1- and pipes -2- for the coolant pump and thermostat housing.
Coolant distributor and connecting pipes
27.3. Replace O-rings -1- and grease new O-rings with Kluberplus Gel (Part No. 000.043.205.93).
O-rings for connecting pipes for coolant distributor
28. Unplug several cable plugs at the engine, unclip all cable holders and unscrew two external Torx(R) screws (E12, M8 x 16) on the cable duct.
^ Solenoid hydraulic valve for camshaft control (top of cylinder head)
^ Fuel pressure sensor on fuel collection pipe, cylinder bank 4-6
^ Oil pressure and temperature sensor on bracket for oil/water heat exchanger
^ Fuel injectors
^ Knock sensors
^ Flow control valve on high-pressure pump
^ Coolant temperature sensor on unit carrier
^ Pressure-regulating valve and oil-level sender on oil pan
28.1. Remove engine wire harness.
29. Remove transport eyebolt.
29.1. Unscrew two external Torx(R) screws (E10, M6 x 25).
30. Remove fuel connection line -1- to the fuel collection pipes.
30.1. Loosen two external Torx(R) screws (E10, M6 x 12) at the clamps.
30.2. Unscrew two external Torx(R) screws (E10) on the fuel line holders. One screw on the center holder M6 x 16 -3- and one screw on the right holder M6 x 60 (screw point for bracket for oil/water heat exchanger) -2-.
30.3. Screw off three union nuts (a/f 17) -4- and remove the line. Collect emerging fuel with a cloth.
Fuel connection line to the fuel collection pipes