100127 Removing engine from transmission and mounting engine on transmission
WM 100127 Removing engine from transmission and mounting engine on transmission
Tools
Technical values
Preliminary work
1. Engine removed. Engine/transmission unit is on the lifting platform.
Removing engine from transmission
CAUTION
Unequal weight distribution of the engine/transmission unit can cause the unit to fall out of the lifting platform supports while it is being raised or lowered.
-> Raise and lower the unit very carefully.
-> Get a second person to perform a visual inspection.
-> Ensure that the axle points are seated correctly with respect to the supports.
-> Make sure the rear supports are seated correctly on the transmission cross member, particularly when lowering the transmission onto the wooden base (the engine has a strong levering effect).
1. Unscrew cardan shaft bolts -arrow- at the transfer gear. Counter with special tool brace 3435 at the triangular flange -A-.
Cardan shaft on transfer gear
2. Loosen ATF lines on transmission and engine. Collect emerging ATF at the transmission. Disconnect ATF lines from the transmission. To do this, unscrew screw -arrow- and remove lines.
ATF line on transmission
3. Remove catalytic converters on both sides from the exhaust manifolds or turbochargers. Expose the lambda sensor cables leading to the catalytic converters (one cable -1- on naturally aspirated engine, two cables on Turbo engine -1- ) while you work. To do this, loosen five nuts on the flange -2- -2- and one screw on the sheetmetal holder under the catalytic converters -3- -3-.
Catalytic converter - Turbo engine
Catalytic converter - naturally aspirated engine
4. Remove sheetmetal holder for left catalytic converter (Turbo only) -9-. Remove the two sheetmetal holders (naturally aspirated engine) later when removing the transmission -6 and 8-.
Holder for catalytic converter - Turbo engine
Holder for catalytic converter - naturally aspirated engine
5. Remove left pressure pipe on the turbocharger. To do this, unclip vent line and loosen clamp -1 and 2-.
Boost pressure pipe
6. Unclip cable for air conditioning compressor and expose it. => Pulling off connector
Pulling off connector
7. On vehicles with PDCC, loosen the hoses on the oil guide housing.
7.1. Remove two nuts. -1-
Removing line bracket for PDCC lines
8. Unscrew fastening screws -1- and unclip lines -2 to 5- at the line bracket -arrows-.
Disconnecting lines on air conditioning compressor
9. Disconnect lines at the tandem pump.
9.1. Unscrew banjo bolt -1- and remove sealing rings -2-. Counter screw torque at the connection.
9.2. Carefully press line -3- to one side -arrow A-.
9.3. Unscrew union nut -4- and carefully pull line -5- down slightly -arrow B-.
Disconnecting lines at the tandem pump
10. Lay PDCC lines aside.
11. Disconnect cable plug on reference mark sender (TDC sender) at the top at the engine cable duct -1-.
Cable plug on reference mark sender
12. Remove reference mark sender at the converter bell housing -arrow-.
Reference mark sender
13. Unclip vent lines at the coolant guide => Vent lines.
Vent lines
14. Disconnect two coolant hoses. To do this, loosen the spring band clamps and move them -1 and 2-.
Coolant hoses
15. Unscrew two coolant pipe screws at the converter bell housing -arrow-.
Coolant pipes on converter bell housing
16. Remove stopper used to seal the converter assembly opening. -1 arrow-
Removing stopper from converter assembly opening
17. Secure transmission to the transmission cross member with a piece of wire or cable to prevent it from tipping over -1- (transmission immediately tips to one side when removing the engine because of the transfer gear) -arrow-.
Securing transmission to prevent it from tipping over
18. Loosen torque converter screws. For details, see -> 373527 Removing and mounting transmission 373527 Removing and mounting transmission
19. Suspend the engine on the workshop crane. For details, see -> 1001IN Lifting V8 DFI engine with a workshop crane 1001IN Lifting the V8 DFI engine with a workshop crane. Make sure that the engine is suspended higher at the front than at the back on the transmission -1 lower, 2 higher-.
Suspending engine
20. Lift the engine/transmission unit until the four screws on the two engine mountings -1- can be removed. => Engine mounting screws
Engine mounting screws
20.1. Remove the engine mountings from the engine carrier and then remove the engine carrier. Lift the engine higher if necessary.
21. Remove lower ATF line. Tie the upper ATF line to the engine with a piece of wire or cable.
22. Unscrew engine/transmission screws leaving only two screws at the side (used for securing engine/transmission unit). Do not forget the two lower screws.
Fastening screws for securing transmission to engine
23. Place a suitable wooden block between the transmission and front-axle carrier. The wooden block must be high enough to allow you to remove the engine easily -arrow-.
Wooden block placed underneath
24. Slowly lower the engine/transmission unit onto the wooden block. The engine is still suspended securely on the workshop crane. Remove the last two screws between the engine and transmission.
Information
- When removing the engine, ensure that the torque converter in the automatic transmission does not slip out of the transmission.
- Keep the torque converter pressed in position using a screwdriver when removing the engine.
25. Remove engine from transmission. Press the torque converter off the drive plate with a screwdriver if necessary.
Transmission without engine on lifting platform
Mounting engine on transmission
1. Insert special tool centering pin 9689 into the torque converter. Roughly position the torque converter and drive plate so that the centering pin passes through a bore on the drive plate.
Torque converter centering pin
2. Tie the upper ATF line to the engine with a piece of wire or cable.
3. Check the position of the transmission. Position the transmission on a suitable wooden block if necessary => Securing transmission to prevent it from tipping over (as for removal) and secure it with a piece of wire or cable => Wooden block placed underneath.
Securing transmission to prevent it from tipping over
Wooden block placed underneath
4. Lift the engine with the workshop crane and move it into installation position with respect to the transmission. Suspend the engine so that it is lower at the back than at the front with respect to the transmission -1 lower, 2 higher-. Put engine and transmission together. Dowel sleeves must slip perfectly into the bores.
Suspending engine
5. Mount the engine without the engine carrier on the transmission.
6. Secure the engine/transmission unit using two screws.
7. Screw the transmission to the engine. Also fit sheetmetal holders for catalytic converters on V8 naturally aspirated engines. -> 373527 Removing and mounting transmission - section on "Mounting" 373527 Removing and mounting transmission
8. Lift the engine/transmission unit, fit the lower ATF line and move the two ATF lines roughly into installation position.
9. Fit engine carrier. Screw engine mountings to the engine carrier. => Engine mounting screws => Tightening torque: 60 Nm (44 ftlb.)
Engine mounting screws
10. Remove wooden block from under the transmission.
Information
- The connection piece for the front-axle final drive vent line must not break off when lowering the engine onto the front-axle carrier. Check this by carrying out a visual inspection.
11. Lower engine with engine carrier onto the front-axle carrier. Make sure that the engine carrier is positioned correctly on the support dome of the lifting platform.
12. Position torque converter correctly with respect to the drive plate. Remove centering pin.
13. If the torque converter turns accidentally, remove rubber strap at the side of the transmission bell housing and turn it back into position using a mirror -1- and screwdriver -2-.
Turning torque converter
14. Screw on torque converter. -> 373527 Removing and mounting transmission - section on "Mounting" 373527 Removing and mounting transmission
15. Fit ATF lines. -> 386219 Removing and installing line for ATF cooling - section on "Installing" Service and Repair
16. Fit coolant pipe on converter bell housing -arrow-. => Tightening torque: 9 Nm (6.5 ftlb.)
Coolant pipes on converter bell housing
17. Connect two coolant hoses. Secure the spring band clamps -1 and 2-.
Coolant hoses
18. Connect cable plug on reference mark sender (TDC sender) at the top at the engine cable duct to the engine wire harness and clip it in -1-.
Cable plug on reference mark sender
19. Fit reference mark sender at the transmission bell housing -arrow-. => Tightening torque: 10 Nm (7.5 ftlb.)
Reference mark sender
20. Clip in vent lines at the coolant guide --.
Vent lines
21. Fit cardan shaft. -> 373527 Removing and mounting transmission - section on "Mounting" 373527 Removing and mounting transmission
22. Provisionally route PDCC lines and move them into installation position.
23. Insert line -5- into the tandem pump -arrow A- and screw in union nut -4- but do not tighten it.
Securing lines on tandem pump
24. Position line -3- on the tandem pump -arrow B- and screw in banjo bolt -1- with new sealing rings -2- , but do not tighten it.
25. Push line bracket -2- with PDCC lines onto the threaded bolts -arrow- and secure with the fastening nuts -1-.
Securing line bracket for PDCC lines
26. Clip lines -2 to 5- into the line bracket -arrows- and secure with the fastening screws -1-.
Securing lines on air conditioning compressor
27. Fit PDCC lines into the pump. For details, see -> 873419 Removing and installing air conditioning compressor - section on "Installing" Service and Repair
28. Plug in connector -arrow B- until the locking lug -arrow a- engages securely and press it into the holder on the air conditioning compressor -arrow A-.
Plugging in connector
29. Fit left pressure pipe on the turbocharger. To do this, clip in vent line and fit clamp -1 and 2-.
Boost pressure pipe
30. Fit sheetmetal holder for left catalytic converter (Turbo only) -9- => Tightening torque: 23 Nm (17 ftlb.).
Holder for catalytic converter - Turbo engine
31. Fit catalytic converters on both sides to the exhaust manifolds or turbochargers. Fit the lambda sensor cables leading to the catalytic converters (one cable -1- on naturally aspirated engine, two cables on Turbo engine -1- ) while you work. To do this, replace five nuts on the flange -2- -2- and fit one screw on the sheetmetal holder under the catalytic converters -3- -3-. => Tightening torque: 23 Nm (17 ftlb.) => Tightening torque: 23 Nm (17 ftlb.)
Catalytic converter - Turbo engine
Catalytic converter - naturally aspirated engine
Subsequent work
1. Install engine. -> 100119 Removing and installing V8 4.8-litre DFI engine - section on "Installing" 100119 Removing and installing V8 4.8-litre DFI engine