Exhaust System: Service and Repair
WM 260119 Removing and installing exhaust system - turbo engine
Tools
Technical values
Preliminary work
1. Remove rear apron.
-> 635519 Removing and installing rear apron .
2. Remove charge-air cooler.
-> 214319 Removing and installing charge-air cooler.
3. Remove heat shields for the catalytic converters.
-> 635019 Removing and installing rear bumper 635019 Removing and installing rear bumper.
4. Remove bumper with heat shield.
-> 635019 Removing and installing rear bumper 635019 Removing and installing rear bumper.
WARNING
Objects or loads falling down
- Risk of squashing or crushing
-> Secure components to prevent them from falling down.
Information
- It may only be supported over a large area at the oil pan.
- Localised loading is not permitted.
Information
- When lowering, the engine must not rest on the rear axle cross member.
5. Lower the engine.
5.1. Support the engine at the oil pan with a transmission jack.
Transmission and unit jack Junior Jack 2.0 WE 1223 ; GA passenger car transmission plate WE 1224
5.2. Loosen two M12 collar nuts (T55) on the engine mountings.
5.3. Slowly lower the engine using the transmission jack.
Removing exhaust system
CAUTION
Hot components
- Risk of burns
-> Let hot components cool down.
-> Wear personal protective gear.
Information
Specifications for wrench sizes (a/f specifications) for screw heads are described as follows:
- Torx screws: (E.) for external Torx, (T.) for internal Torx.
- Hexagon-head bolts (internal and external hexagon): Wrench size (a/f)
1. Unclip and pull off plug connection for the oxygen sensors -1 and 2- in the engine compartment.
1.1. Connectors on cylinder bank 1-3:
Oxygen sensor connectors, cylinder bank 1-3
1.2. Connectors on cylinder bank 4-6:
Oxygen sensor connectors, cylinder bank 4-6
2. Guide the oxygen sensor connectors through at the side of the engine as far as the catalytic converters and unclip the oxygen sensor cables from the holders -arrows-.
Oxygen sensors at catalytic converter
3. Remove flange bolts securing catalytic converter to the turbocharger.
3.1. Loosen and screw off four M8 hexagon nuts (a/f 13) -1- on both cylinder banks.
Turbocharger flange at the top on cylinder bank 1-3
Flange bolts at the bottom:
Turbocharger flange at the bottom on cylinder bank 1-3
4. Loosen rear silencer mounting.
4.1. Loosen two M8 x 50 cheese head bolts (hexagon socket head, a/f 6) -2- for the restraining straps.
Rear silencer mounting
4.2. Slide the restraining straps outwards off the holders -arrow-.
Restraining straps for rear silencer
CAUTION
Heavy components
- Risk of squashing
-> Wear personal protective gear.
-> Get someone to help if necessary.
5. Pull the exhaust system to the rear and off the studs on the turbochargers.
Only remove the exhaust system with the help of another person.
6. Replace all metal seals.
Installing exhaust system
1. Fit new metal seals and slide them onto the sealing face on the turbochargers.
CAUTION
Heavy components
- Risk of squashing
-> Wear personal protective gear.
-> Get someone to help if necessary.
2. Slide the exhaust system onto the bolts on the turbochargers.
Only install the exhaust system with the help of another person.
3. Fit and tighten four new M8 hexagon nuts (a/f 13) on the turbocharger flange on both cylinder banks.
Turbocharger flange at the top on cylinder bank 1-3
Flange bolts at the bottom:
Turbocharger flange at the bottom on cylinder bank 1-3
=> Tightening torque: 25 Nm (19 ftlb.)
4. Slide two restraining straps on the rear silencer over the holder -arrow- and align them using one M8 x 50 cheese head bolt (hexagon socket head, a/f 6) on each one.
Restraining straps for rear silencer
4.1. Tighten cheese head bolts -2-.
Rear silencer mounting
=> Tightening torque: 15 Nm (11 ftlb.)
5. Guide the cable plugs for the oxygen sensors at the side of the engine to the plug connection in the engine compartment and clip the cables into the holders -arrows-
Oxygen sensors at catalytic converter
6. Close and clip in plug connections -1 and 2- for the oxygen sensors in the engine compartment.
Oxygen sensor connectors, cylinder bank 1-3
Subsequent work
WARNING
Objects or loads falling down
- Risk of squashing or crushing
-> Secure components to prevent them from falling down.
Information
- It may only be supported over a large area at the oil pan.
- Localised loading is not permitted.
Information
- When lowering, the engine must not rest on the rear axle cross member.
1. Secure the engine.
1.1. Move the engine into installation position using the transmission jack.
1.2. Fit and tighten two M12 collar nuts (T55) on the threaded bolts for the engine mountings.
=> Tightening torque: 85 Nm (63 ftlb.)
1.3. Lower the transmission jack and move it out of the work area.
2. Install bumper and heat shield.
-> 635019 Removing and installing rear bumper 635019 Removing and installing rear bumper.
3. Install heat shields for the catalytic converters.
-> 635019 Removing and installing rear bumper 635019 Removing and installing rear bumper.
4. Install charge-air cooler.
-> 214319 Removing and installing charge-air cooler.
5. Install rear apron.
-> 635519 Removing and installing rear apron .