Set Basic Position Of Camshafts - AR05.20-P-6020MNA

Engine 176 in model 463 up to model year 2019

Engine 177 in model 205

Engine 178 in model 190

Shown on left cylinder head

Courtesy of MERCEDES-BENZ USA

Shown on left cylinder head

Courtesy of MERCEDES-BENZ USA

	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
	Risk of injury. Moving parts can pinch, crush or, in extreme cases even sever extremities.	No parts of the body or limbs should be within the operating area of mechanical components when moving components.	AS00.00-Z-0009-01A
	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 to skin and eyes due to handling of engine oil. Risk of poisoning caused by swallowing engine oil	Wear protective gloves, protective clothing and safety glasses. Do not fill engine oil into beverage containers.	AS18.00-Z-0001-01A
	Notes on avoiding damage through contamination and foreign objects		AH00.00-P-5000-01A
	Remove
1	Remove left cylinder head cover.	Engine 178 in model 190 (except 190.381)	AR01.20-P-5013MNB
		Engine 178.9 in model 190.381	AR01.20-P-5013MNJ
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205	AR01.20-P-5013MNA
		WIS Service Media multimedia:A supplement to the article is available.
2	Remove right cylinder head cover.	Engine 178 in model 190 (except 190.381)	AR01.20-P-5012MNB
		Engine 178.9 in model 190.381	AR01.20-P-5012MNJ
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205	AR01.20-P-5012MNA
3	Install brackets (1, 2, 3).		AR05.20-P-6020-03MNA
		Holding device	Fig 1
4	Turn engine at center bolt of the crankshaft through two revolutions, place engine on cylinder 1 at 400 KW after ignition TDC of cylinder 1 and mark with a drift.		AR05.10-P-7620-04MNA
		Turn engine in direction of engine rotation only.
		Socket wrench bit	Fig 4
		Drift	Fig 3
5	Remove secondary chain drive chain tensioners on left and right.		AR05.10-P-7800MNA
		Do not turn the engine while the chain tensioner is removed. Otherwise damage will occur. Remove secondary chain drive chain tensioners on left and right without turning the crankshaft.
6	Insert holding device(6) between camshaft positioners(7) and tighten.	Holding device	Fig 1
7	Release camshaft positioners (7) from camshafts and remove with holding device (6).		AR05.20-P-7204MNA
		The camshaft positioners (7) and their control valves must always be replaced, as they do not suffer any visible damage during removal. Engine damage can occur otherwise.
	Adjust
8	Turn camshafts in the basic position.	The positions (arrows) of the camshaft must point upwards.
		Engine 176 in Model 463 up to Model year. 2019, Engine 177 in Model 205, Engine 178 in Model 190, with Camshafts with 0 4 mm Drill Socket wrench bit	Fig 2
		Engine 176 in Model 463 up to Model year. 2019, Engine 177 in Model 205, Engine 178 in Model 190, with Camshafts with 0 5 mm Drill Socket	Fig 5
9	Install aligners (5).	The aligners (5) must be installed without applying force. Otherwise the timing will be off. The aligners (5) are not suitable for bringing the camshafts into position. Otherwise damage to the camshafts will occur.
		Holding device	Fig 1
		Engine 176 in Model 463 up to Model year. 2019, Engine 177 in Model 205, Engine 178 in Model 190, with Camshafts with 0 4 mm Drill Socket wrench bit	Fig 2
		Engine 176 in Model 463 up to Model year. 2019, Engine 177 in Model 205, Engine 178 in Model 190, with Camshafts with 0 5 mm Drill Socket	Fig 5
	Install
10	Position new camshaft positioners (7) on camshafts, tighten new control valves slightly by hand and release by 1/4 revolution.		AR05.20-P-7204MNA
11	Install bracket (4).	Holding device	Fig 1
12	Check that tensioning rails of the secondary chain drive are seated in the middle.
13	Install secondary chain drive chain tensioner on the left and right.	Install secondary chain drive chain tensioners on left and right without turning the crankshaft.	AR05.10-P-7800MNA
14	Insert holding device(6) between camshaft positioners(7) and tighten.	Holding device	Fig 1
15	Tighten control valves of camshaft positioners (7).		AR05.20-P-7204MNA
16	Remove holding device(6).	Holding device	Fig 1
17	Remove aligners (5).	Holding device	Fig 1
18	Remove drift from belt pulley.	Drift	Fig 3
19	Turn engine at center bolt of the crankshaft through two revolutions, place engine on cylinder 1 at 400 KW after ignition TDC of cylinder 1 and mark with a drift.		AR05.10-P-7620-04MNA
		Turn engine in direction of engine rotation only.
		Socket wrench bit	Fig 4
		Drift	Fig 3
20	Install aligners (5).	Install aligners (5) without applying force. Otherwise the timing will be off.
		Holding device If aligners (5) cannot be installed without force application ↓ Set basic position of camshafts again.	Fig 1
21	Remove aligners (5).	Holding device	Fig 1
22	Remove bracket (4).	Holding device	Fig 1
23	Remove brackets (1, 2, 3).		AR05.20-P-6020-03MNA
		Holding device	Fig 1
24	Remove drift from belt pulley.	Drift	Fig 3
25	Install right cylinder head cover.	Engine 178 in model 190 (except 190.381)	AR01.20-P-5012MNB
		Engine 178.9 in model 190.381	AR01.20-P-5012MNJ
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205	AR01.20-P-5012MNA
26	Install left cylinder head cover.	Engine 178 in model 190 (except 190.381)	AR01.20-P-5013MNB
		Engine 178.9 in model 190.381	AR01.20-P-5013MNJ
		Engine 176 in model 463 up to model year 2019 Engine 177 in model 205	AR01.20-P-5013MNA