Remove and installing catalytic converter or front exhaust system - AR49.10-P-5531F

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ENGINE 120

Fig 1: Identifying Catalytic Converter Or Front Exhaust System Remove/Install Components

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Remove/install
1	Remove and install bottom engine compartment paneling
2	Remove / install exhaust system as from flange connection	Model 129	AR49.10-P-7280FA
		Model 140	AR49.10-P-7280FB
3	Detach connectors for O₂ sensor on the left and right (G3/3x1, G3/4x1)	By loosening union nut
4	Remove bolts (1) on rear exhaust manifolds on left/right	If bolts are sluggish, or thread damaged: ↓
		Replace the rivet nuts in the exhaust manifold.	AR49.10-P-5531-01DA
			Figure
			*BA14.10-P-1002-01B
5	Disconnect flange connections on exhaust pipes at front (15, 16)		*BA49.10-P-1002-01A
6	Unscrew nuts (6a) on carriers (10) and remove catalytic converter (2)		*BA49.10-P-1001-01A
7	Remove O2 sensors (G3/3, G3/4)	When installing coat thread on oxygen sensor with heat-resistant lubricant	*BR00.45-Z-1005-06A
			*BA14.00-P-1001-01A
			Figure
8	Remove front exhaust pipe (15, 16) by removing bolts (1) on front exhaust manifolds on left/right	If bolts are sluggish, or thread damaged: ↓
		Replace the rivet nuts in the exhaust manifold.	AR49.10-P-5531-01DA
			Figure
			*BA49.10-P-1002-01A
	Checking
9	Check flange (5a), graphite sealing rings (5b) for reusability	Replace if necessary
10	Install in the reverse order

O2 SENSOR

Number	Designation		Engine 104, 111, 119, 120, 137, engine 166 in model 168
BA14.00-P-1001-01A	O₂ sensor at exhaust pipe/ exhaust manifold	Nm	55

EXHAUST MANIFOLD

Number	Designation		Engine 120
BA14.10-P-1002-01B	Flange connection, exhaust manifold and front exhaust pipes	Nm	20

EXHAUST SYSTEM

Number	Designation		ENGINE 104, 120
BA49.10-P-1001-01A	Nut, exhaust bracket to transmission side support	Nm	25
BA49.10-P-1002-01A	Bolt of flange connection to exhaust pipe	Nm	20

REPAIR MATERIALS

Number	Designation	Order number
BR00.45-Z-1005-06A	Paste	A 000 989 76 51

Fig 2: Identifying Box Wrench Bit, Delco R4 And A6 (000 589 71 03 00)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Fig 3: Identifying Cocking Bolt (103 589 01 39 00)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.