Remove/Install Oil Separator On Cylinder Head Cover - AR01.20-P-9691MRU

Model 172, 205, 213, 238, 253 with engine 274.9 

with code 945 (China Stage 6 exhaust treatment) 

Model 172, 205, 213, 253 with engine 274.9 

with code 494 (US version) 

Shown on model 205 

Fig 1: Oil Separator On Cylinder Head Cover Components Location - Model 213 With Engine 274.9 With Codes 945; 494 (Shown On Model 205)

Courtesy of MERCEDES-BENZ USA

	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
	Risk of explosion  caused by fuel igniting, risk of poisoning caused by inhaling and swallowing fuel as well as risk of injury to eyes and skin caused by contact with fuel.	No fires, sparks, open flames or smoking. Pour fuels into suitable and appropriately marked containers only. Wear protective clothing when handling fuel.	AS47.00-Z-0001-01A
NOTICE	Information on preventing damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
NOTICE	Notes on threaded connections fastened using a tightening angle-based tightening process		AH00.00-P-0020-01A
NOTICE	Notes on avoiding damage through contamination and foreign objects		AH00.00-P-5000-01A
	General information on work on gasoline direct injection system		AH07.00-P-2000-01A
	Remove/install
1	Remove upper engine cover.	: Only install upper engine cover after the leak test.
2	Remove soundproofing.	Model 172 with engine 274.9 with code 494 (US version) Model 172 with engine 274.9 with code 945 (China Stage 6 exhaust treatment)	AR94.30-P-5400MRE
		Model 213 with engine 274.9 with code 494 (US version) except code 920 (Direct fuel injection with stratified charging) Model 213 with engine 274.9 with code 945 (China Stage 6 exhaust treatment) except code 920 (Direct fuel injection with stratified charging) Model 238 with engine 274.9 with code 945 (China Stage 6 exhaust treatment) except code 920 (Direct fuel injection with stratified charging) : Install soundproofing only after the leak test.	AR94.30-P-5410MRD
3	Disconnect ground line from battery.	Model 238 with engine 274.9 with code 945 (China Stage 6 exhaust treatment)	AR54.10-P-0003LWO
		Engine 274.9 in model 172 with code 494 (US version) Engine 274.9 in model 172 with code 945 (China Stage 6 exhaust treatment)	AR54.10-P-0003W
		Model 205, 213, 253 with engine 274.9 with code 494 (US version) Model 205, 213, 253 with engine 274.9 with code 945 (China Stage 6 exhaust treatment)	AR54.10-P-0003LW
4	Remove center and rear sections of lower engine compartment lining.	Engine 274.9 in model 172, 205, 213, 238, 253 with code 945 (China Stage 6 exhaust treatment) Engine 274.9 in model 172, 205, 213, 253 with code 494 (US version) Model 213 with engine 274.9 with code 494 (US version) Model 213, 238 with engine 274.9 with code 945 (China Stage 6 exhaust treatment)	AR61.20-P-1105LWE
		Engine 274.9 in model 205 with code 494 (US version) Engine 274.9 in model 205 with code 945 (China Stage 6 exhaust treatment) Engine 274.9 in model 253 with code 494 (US version) Engine 274.9 in model 253 with code 945 (China Stage 6 exhaust treatment) : Only install center and rear lower rear engine compartment paneling again after leak test.	AR61.20-P-1105LW
5	Release and disconnect electrical connector of high-pressure fuel pump.
6	Remove cable duct on cylinder head cover, shielding of high-pressure fuel pump and oil separator (27).	M6 X 1	*BA00.10-P-1002-04A
7	Remove shielding of high-pressure fuel pump.	: Observe tightening procedure for shielding over high-pressure fuel pump.	AR07.02-P-0815-01MR
		Bolt for high-pressure pump shielding	*BA07.02-P-1004-01D
8	Release fuel pressure in the fuel high-pressure circuit.		AR07.03-P-1460-02MM
9	Remove high-pressure line (28) and seal connections with suitable stop plugs.	Do not kink or bend high-pressure line (28). Otherwise damage and leaks can occur.	AR07.03-P-1010-02MR
		Union nut, fuel line to fuel distributor	*BA07.03-P-1001-01F
		Union nut, fuel line to high-pressure pump	*BA07.03-P-1002-01F
		Box wrench bit	Fig 3
		Record plug	Fig 2
10	Remove oil separator (27) from cylinder head cover.	: Replace seal.
		Screw/bolt, oil separator to cylinder head cover	*BA01.20-P-1007-01R
11	Release and disconnect electrical connector for PZEV vent line contact switch on crankcase and place to one side.
12	Remove vent line (29) from crankcase.	: Replace sealing ring.
		Bolt, bleed line for oil separator to crankcase	*BA01.20-P-1004-01R
13	Remove oil separator (27) upward.
14	Check sealing cone on high-pressure line (28).	Check sealing cones of high-pressure line (28) before installation. Otherwise damage and leaks can occur.	AR07.03-P-1010-03MM
		Assembly cleaner	*BR00.45-Z-1028-04A
15	Install in the reverse order.
	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
16	Carry out engine test run and check engine for proper operation and leak tightness.

Fig 2: Identifying Record Plug (129 589 00 91 00)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Box Wrench Bit (000 589 80 03 00)

Courtesy of MERCEDES-BENZ USA