Part 1
WM 100119 Removing and installing engine
Tools
Preliminary work
Preliminary work for removing and installing engine
1. Read out the DME fault memory.
2. For vehicles with air suspension:
Move air suspension into service position. -> 4301IN Bleeding and filling levelling system 4301IN Bleeding and filling the levelling system
3. Remove engine guard with transverse strut. -> 108019 Removing and installing engine guard - section on "Removing" 108019 Removing and installing engine guard
4. On vehicles with 19-inch brake system: Remove the air guide at the anti-roll bar. -> 407719 Removing and installing front stabilizer (PDCC) - section on "Removing" 407719 Removing and Installing Front Anti-Roll Bar (PDCC)
5. Disconnect the battery. -> 2X00IN Work instructions after disconnecting the battery 2X00IN Work instructions after disconnecting the battery
6. Remove front wheels. -> 440519 Removing and installing wheel - section on "Removing" Removal and Replacement
7. Remove the front wheel housing liners. -> 505619 Removing and installing front wheel housing liner - section on "Removing" Service and Repair
8. Move bonnet into service position. -> 553119 Removing and installing front pneumatic spring - section on "Removing" Service and Repair
9. Remove right cross panel. -> 508119 Removing and installing cross panel - section on "Removing" Service and Repair
10. Remove engine compartment trim panels. -> 700219 Removing and installing front trim (engine compartment) - section on "Removing"
11. Loosen the torque support. -> 103719 Removing and installing torque support - section on "Removing" Service and Repair
12. Remove design cover on throttle valve. -> 108319 Removing and installing engine cover (design cover) - section on "Removing" 108319 Removing and installing engine cover (design cover).
13. Drain coolant. -> 193817 Draining and filling coolant (includes bleeding) Service and Repair
14. Evacuate the air conditioning system. -> 870317 Draining and filling refrigerant Service and Repair
Tools and materials
The following tools are described in Tools and Equipment, Chapter 3.0.13 "WE 1206" (exceptions are noted).
Lifting platform
Tool overview
Complete structure of the base carrier with mounting mandrels
Removing engine
WARNING
Highly inflammable or explosive materials
- Danger of fire or explosion
-> Avoid contact with hot parts or sources of ignition.
-> Use suction to remove ignitable vapors.
-> Attach warning sign in a clearly visible position.
WARNING
Caustic fluids
- Danger of chemical burns
-> Avoid contact with caustic fluid.
-> Wear personal protective gear.
-> Ensure that there is good ventilation.
-> If you do come into contact, wash off immediately with plenty of warm water and contact a doctor if necessary.
NOTICE
Aggressive fluids
- Risk of damage to components and surfaces
-> Do not spill fluids.
-> In the event of contact, wash the component or surface with water.
-> Replace components that are already damaged.
Information
- For installation, it is a good idea to mark the installation position of the front-axle carrier diagonally at at least two places on the body. To do this, place the marks vertically with respect to the floor of the body using a felt-tip pen (e.g. mark along the front-axle carrier mount with the pen). This makes it easier to correctly position the front-axle carrier on the body during re-installation.
Information
- Because of the high loosening torques, the four fastening screws on the front-axle carrier and the two screws on the engine transverse bar can now be loosened. Loosen the screws by a maximum of one turn.
Information
- When lowering the engine, make sure that cables or lines are not trapped accidentally between the engine and body. To prevent this, a second person must make sure that the cables and lines do not get caught.
Information
- The pictures shown in this document may differ from the original.
- However, this does not affect the validity and relevance of the pictures.
1. Release electric plug connection -1- - M - on the DME control unit -2- ( -a- ) and pull it off -A-.
Plug connection on DME control unit
2. Loosen fastening nut -1- for ground point at the body and remove ground cable -2- to the DME control unit.
Cut the tie-wrap if necessary.
Ground point on body
3. Remove the tie-wrap -3- if necessary.
4. Open the cover of the front relay box in the plenum panel. -> 970955 Replacing sub-part of wire harness in engine compartment at the front left 970955 Replacing sub-part of wire harness in engine compartment at the left
5. Release and unplug the three electric plug connections -1- on the engine wire harness.
Disconnecting plug connections
6. Unclip the engine wire harness -1- in the plenum panel from the retaining clips -2- and remove it.
Engine wire harness in plenum panel
7. Disconnect B+ transfer point at the left of the engine compartment.
B+ transfer point
8. Release electric plug connections -1- at the left cross panel -a, b- and pull them off -A, B-.
Plug connections at left cross panel
9. Release electric plug connections -1- at the right cross panel -a, b- and pull them off -A, B-.
Plug connections at right cross panel
10. Lay the engine wire harness on the engine and secure it.
11. Remove intake pipe. -> 243519 Removing and installing air box for throttle housing (Y-shaped pipe) - section on "Removing" 243519 Removing and installing cowl for throttle housing (Y-pipe)
12. Drain the hydraulic fluid reservoir -1- and the PDCC reservoir -2- , if necessary, using a suitable tool.
Then remove the hoses -3, 4- at the tanks and close them off using suitable stoppers. -> 489719 Removing and installing reservoir - section on "Removing" Service and Repair, -> 430955 Replacing reservoir (PDCC) - section on "Removing" Service and Repair
Hoses for hydraulic reservoir
13. Loosen the fuel line -1- at the plenum panel.
Plenum panel lines
14. Release the clamp -2- on the tank ventilation line.
15. Pull the vacuum hose -3- off the lower part -4- of the line.
16. Disconnect the coolant line -1- from the coolant reservoir -2- at the bleeder valve.
Coolant lines at the reservoir
17. Loosen the clamp -3- on the coolant hose -4- at the coolant reservoir -2-.
Pull off the coolant hose.
18. Loosen clamps -1- on the coolant hoses -2- at the top of the engine.
Coolant hoses at top of engine
Pull off coolant hoses -2-.
19. Loosen the clamp -1- on the vacuum line -2- at the vacuum pump -3- and pull off the vacuum line.
Vacuum pump line
20. Raise the vehicle.
21. Unscrew fastening screws -1, 2- for holders -3, 4- for brake hydraulic lines.
Holders for hydraulic lines
22. Loosen holders from the wheel bearing housing -5-.
23. Release electric plug connections -1- for the speed sensor on the wheel bearing housing -a- and pull them off -A-.
Plug connections on wheel bearing housing (shown as an example)
24. Remove the brake caliper and suspend it at a suitable position in the wheel arch => Suspending brake caliper (do not open brake hydraulics!).
Also protect the brake caliper (e.g. with a cloth or suitable rubber mat) to prevent damage to the paintwork.
Suspending brake caliper
25. Remove fastening screws -1- for the connecting links -2- at the bottom of the anti-roll bar -3-.
Connecting link for anti-roll bar
26. Press out the ball joint between the wheel carrier and upper wishbone using ball joint puller T10187.
27. Unscrew the fastening screw -2- for the spring strut -3- and at the same time, raise the axle support -1- as far as required using a suitable jack -4- so that the fastening screw can be unscrewed easily.
Removing spring strut mounting
28. Disconnect the ground point on the right longitudinal member. -arrow-
Ground point on right longitudinal member
29. Loosen the fastening screw -1- on the holder -2- for ATF lines -3- at the thermostat -4-.
ATF lines from thermostat to transmission
30. Place a suitable container underneath to catch emerging ATF.
- Pull ATF lines out of the thermostat.
- Close off the ATF lines and bores on the thermostat using suitable stoppers.
31. Loosen fastening screws -1- on the heat shield -2- at the steering gear.
Heat shield for steering gear
Remove heat shield -2-.
32. Loosen the clamping screw -1- on the steering column -2- at the steering gear -3-.
Loosening steering column at the steering gear
Slide the steering column -2- upwards -arrow- and pull it down off the steering gear -3- ( -A- ).
33. Pull clamps -1- off the coolant lines -2- for the heating water heat exchanger in the engine compartment at the rear left on the wheel housing.
Coolant lines in front left wheel housing
34. Pull off coolant hoses -2-.
35. Loosen the fastening screw -1- for the refrigerant line -2- at the front left longitudinal member -3- and pull out the line.
Front left refrigerant line
36. Remove the line -1- from the air-conditioning compressor to the condenser -2-.
Line from air-conditioning compressor to condenser
36.1. To do this, unscrew the fastening screw -3- for the line -1- at the condenser -2-.
36.2. Close off lines and connection pieces.
37. Loosen the clamp -1- on the hydraulic line -2- in the front left wheel housing and pull the hose off the hydraulic line.
Front left hydraulic line
Close off the line and connection piece using suitable stoppers.
38. Loosen the cardan shaft at the transfer gear using a mounting lever and tie it up. -> 390219 Removing and installing cardan shaft - section on "Removing" 390219 Removing and Installing Front Cardan Shaft
39. Release electric plug connections -1, 2- at the right of the transfer gear -a, b- and pull them off -A, B-.
Plug connections for transfer gear at the right
40. Release electric plug connections -1, 2- at the bottom of the transfer gear -a, b- and pull them off -A, B-.
Plug connections for transfer gear at the bottom
41. Mark gearshift position - N - -1- on automatic transmission -2- with a suitable pen -A-.
Marking gearshift position
42. Remove shift cable -3- on automatic transmission -4-. -> 371519 Removing and installing selector lever cable - section on "Removing" Service and Repair
Removing shift cable
42.1. Unclip the cable -3- at the front of the ball joint -1- using disassembly tool Nr.21.
42.2. Unscrew fastening screws -2- on the shift cable -3-.
43. Loosen fastening nuts -8- on the exhaust clamp (clamping sleeve) -3- between the catalytic converter and exhaust system. Slide exhaust clamps onto the exhaust system. The exhaust clamps must not be re-used. -> 260119 Removing and installing exhaust system - section on "Removing" Service and Repair
Loosening clamps
44. Mark the installation position of the front-axle carrier diagonally at at least two places on the body using a felt-tip pen. This makes it easier to correctly position the front-axle carrier on the body during reinstallation. => Marking installation position of front-axle carrier
Marking installation position of front-axle carrier
45. Set up the lifting platform according to instructions -> 100119 Removing and installing engine - section on "Tools and materials". Then position it under the engine and raise it. When you do this, ensure that the positioning guides of the lifting platform are inserted into the body. => Lifting platform under engine
Lifting platform under engine
46. The -arrows- show the mounting points for the mounting frame in the front-axle carrier (view from below here).
Mounting points for front-axle carrier
47. Position lifting platform in the front-axle carrier in the mounting points provided -(arrows)- , -4 into the body-.
Lifting platform
48. Secure the wheel bearing housing. To do this, turn the rubber discs upwards until they are set under the steering knuckle. Then tighten the retaining brackets on the wheel hub and lifting platform. -arrow-
Securing wheel bearing housing
49. Mark the final position of the lifting platform -1- on the workshop floor using a suitable tool, e.g. adhesive tape -A-.
Position of lifting platform
50. Loosen the transmission cross member. To do this, loosen the four fastening screws -A-.
Fastening screws on transmission cross member
51. Secure the engine/transmission unit. Then secure the mounting mandrels on the engine transverse bar with the locking screws.
52. Loosen the four fastening screws on the front-axle carrier and the two fastening screws on the engine transverse bar. -arrows-
Fastening screws for front-axle carrier and fastening screws for engine transverse bar (centre)
53. Get a second mechanic to help.
1st mechanic: Lower the lifting platform slowly by approx. 20 to 30 cm.
2nd mechanic: Observe the lowering process and check that the components, hoses and lines have sufficient clearance.