Remove/install catalytic converter - AR49.10-P-5500GQC

ENGINE 276.8 in MODEL 166, 251 

Shown on model 166 

Fig 1: Identifying Catalytic Converter Remove/Install Components - Shown On Model 166

Courtesy of MERCEDES-BENZ USA

	Risk of injury  caused by scraping or cutting body parts on sharp vehicle parts	Always wear protective gloves when working on or near sharp and non-deburred vehicle parts. Deburr repair panels.	AS00.00-Z-0017-01A
	Risk of injury  . Skin or eye injuries may result when handling hot or glowing objects.	Wear protective gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
	Notes on self-locking nuts and bolts		AH00.00-N-0001-01A
	Remove/install
1	Remove partition wall between wheel wells	ENGINE 276.8 in MODEL 251
			AR62.30-P-2400RT
2	Remove windshield wiper system	ENGINE 276.8 in MODEL 251
			AR82.30-P-6400RT
3	Remove air filter housing on the right or air filter housing on the left		AR09.10-P-1150GQC
	Risk of death  caused by vehicle slipping or toppling off of the lifting platform.	Align vehicle between vehicle lift columns and position the four support plates at the vehicle lift support points specified by the vehicle manufacturer.	AS00.00-Z-0010-01A
4	Lift/jack up vehicle		AR00.60-P-1000RT
5.1	Remove underfloor paneling	ENGINE 276.8 in MODEL 166
			AR61.30-P-1001GQ
5.2	Remove engine compartment paneling	ENGINE 276.8 in MODEL 251
			AR61.20-P-1105RT
	Remove left catalytic converter (2)
6	Remove rear left heat shield (8f)	Bolt, turbocharger shield bracket to cylinder head	*BA09.40-P-1012-01W
		Bolt/nut for shield attachment	*BA09.40-P-1011-01W
7	Disconnect electrical connection for left oxygen sensor downstream of CAT (G3/5x1) or electrical connection for left oxygen sensor downstream of CAT (G3/3x1)
8	Remove left diagonal strut and left cross strut	ENGINE 276.8 in MODEL 166
			AR22.10-P-1180GQ
			AR22.10-P-1180GZD
9	Detach left CAT (2) from transmission holder (9)	ENGINE 276.8 in MODEL 166	*BA49.10-P-1019-01AK
		ENGINE 276.8 in MODEL 251	*BA49.10-P-1001-01X
10	Detach left CAT (2) from center muffler (6) and turbocharger and remove to the rear and downwards	To do this unfasten clamps (1, 5). The dowel pin on hot end, must  be set in the notch on the turbocharger. After screwing down the clamp (1) using the prescribed torque there should be no gap anymore on the clamp lock.
11	Detach left oxygen sensor upstream of CAT (G3/3) and left oxygen sensor downstream of CAT (G3/5) from left CAT (2)	Only when replacing the left catalytic converter (2).
	Remove right catalytic converter (3)
12	Remove rear right heat shield (8f)	Bolt/nut for shield attachment	*BA09.40-P-1011-01W
13	Disconnect electrical connection for left oxygen sensor downstream of CAT (G3/6x1) or electrical connection for right oxygen sensor downstream of CAT (G3/4x1)
14	Remove right cross strut	ENGINE 276.8 in MODEL 166	AR22.10-P-1180GQ
		ENGINE 276.8 in MODEL 251	AR22.10-P-1180GZD
15	Detach right CAT (3) from transmission holder (9)	ENGINE 276.8 in MODEL 166	*BA49.10-P-1019-01AK
		ENGINE 276.8 in MODEL 251	*BA49.10-P-1001-01X
16	Detach right CAT (3) from center muffler (6) and turbocharger and remove to the rear and downwards	To do this unfasten clamps (1, 4). The dowel pin on hot end, must  be set in the notch on the turbocharger. After screwing down the clamp (1) using the prescribed torque there should be no gap anymore on the clamp lock.
17	Detach right oxygen sensor upstream of CAT (G3/4) and right oxygen sensor downstream of CAT (G3/6) from right CAT (3)	Only when replacing right catalytic converter (3).
18	Install in the reverse order
19	Clear fault memory using the diagnostic system
			AD00.00-P-2000-04A
	Check
	Risk of accident  from vehicle starting off by itself when engine running. Risk of injury  (bruises and burns) resulting from working on the engine while it is being started or when it is running.	Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
20	Carry out an engine test run and check exhaust system for leak tightness

TURBOCHARGER

Number	Designation			ENGINE 276.8
BA09.40-P-1011-01W	Bolt/nut for shield attachment	M6	Nm	9

TURBOCHARGER

Number	Designation			ENGINE 276.8
BA09.40-P-1012-01W	Bolt, turbocharger shield bracket to cylinder head	M7	Nm	14

EXHAUST SYSTEM

Number	Designation		ENGINE 272, 273, 276 in MODEL 251
BA49.10-P-1001-01X	Bolt, catalytic converter bracket to catalytic convertor	Nm	20

EXHAUST SYSTEM

Number	Designation		ENGINE 276 in MODEL 166
BA49.10-P-1019-01AK	Screw/bolt, exhaust system bracket to exhaust system	Nm	20