Muffler: Service and Repair

WM 263319 Removing and installing rear silencer

Tools





Technical values





Preliminary work

1. Remove rear underbody panel. -> 519419 Removing and installing rear underbody panel 519419 Removing and Installing Cover for Rear Underbody

Removing rear silencer

1. Remove connecting strut between rear mufflers. -3- or -3-





Exhaust system for naturally aspirated engines (tailpipe covers not shown)









Exhaust system for turbocharged engines (tailpipe covers not shown)





2. There is a small notch on the underside of the exhaust pipes that is level with the rear axle transmission. The notch marks the connection point. -arrow-





View shows connection point

3. Place the pipe cutter chain chain pipe cutter Nr.166 or ratchet pipe cutter Nr.166-1 (or similar tool) around the exhaust pipe near the notch and engage in the other end of the pipe cutter. Then clamp the chain firmly by twisting the handle. => Laying chain of pipe cutter around exhaust pipe





Laying chain of pipe cutter around exhaust pipe

4. Swivel the pipe cutter to and fro in wide movements until the pipe is cut through. While doing this, keep tightening the chain by twisting the handle. => Cutting through pipe with pipe cutter





Cutting through pipe with pipe cutter

5. In the case of a flap exhaust system (with vacuum units), disconnect vacuum hose for flap actuation from vacuum unit.
6. Remove rear holder of the relevant rear muffler. Remove two fastening screws for this purpose -1-.





Rear muffler holder

7. Remove rear muffler.
8. Deburr cut on inside and outside of exhaust pipe. If necessary, remove rust from exhaust pipe using suitable polishing agents and manually restore to roundness.

Installing rear silencer

1. Fit new suspension rubbers or holders if necessary.
2. Push new exhaust clamp onto exhaust pipe.
3. Lift rear muffler into installation position with the help of a second mechanic. Tighten both fastening screws to the specified tightening torque -1-. => Tightening torque: 23 Nm (17 ftlb.)





Rear muffler holder

4. Move new exhaust clamp (clamping sleeve) to installation position and install. Screw connection must point downwards. Adjust to maximum inclination and ensure that assembly length of both exhaust pipes is the same. => Installation position of exhaust clamp => Adjustment value: 10° => Tightening torque: 23 Nm (17 ftlb.)





Installation position of exhaust clamp





5. Install connecting strut between rear mufflers. -3- or -3- => Tightening torque: 23 Nm.





Exhaust system for naturally aspirated engines (tailpipe covers not shown)









Exhaust system for turbocharged engines (tailpipe covers not shown)





6. In the case of a flap exhaust system (with vacuum units), connect vacuum hose for flap actuation to vacuum unit.

Subsequent work

1. Install rear underbody panel, -> 519419 Removing and installing rear underbody panel 519419 Removing and Installing Cover for Rear Underbody