Remove/Install Fuel Rail With Fuel Injectors - AR07.03-P-1052MRA

Engine 274.9 in model 205

Engine 274.9 in model 253

Courtesy of MERCEDES-BENZ USA

Fig 1: Fuel Rail With Fuel Injectors Components Location - Engine 274.9 In Model 253

Courtesy of MERCEDES-BENZ USA

	Risk of explosion caused by fuel igniting. Risk of injury to skin and eyes caused by fuel spraying out at high pressure	Keep all ignition sources out of hazard area. Do not carry out any work on system when it is pressurized.	AS07.16-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
	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
	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 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
	Information on preventing damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
	Notes on threaded connections fastened using a tightening angle-based tightening process		AH00.00-P-0020-01A
	Notes on avoiding damage through contamination and foreign objects		AH00.00-P-5000-01A
	Notes on safety-relevant components		AH00.00-Z-0019-01A
	Note on calculation of tightening torque when using insertion or socket tools with various effective lengths		AH00.00-P-0015-01CW
	General information on work on gasoline direct injection system		AH07.00-P-2000-01A
	Remove
1	Remove center and rear sections of lower engine compartment lining.	Vehicles with diagnostic socket
			AR61.20-P-1105LW
2.1	Remove fuel pressure via the service connection.	Vehicles with diagnostic socket
			AR07.03-P-1460-01MR
		Dust cap at service connection	*BA07.03-P-1003-01F
		Pressure hose	Fig 8
2.2	Reduce fuel pressure via vehicle diagnosis system.	Vehicles without diagnostic socket
			AD00.00-P-2000-04B
		To do so, select following menu items: ME-SFI [ME] control unit → Actuation → Actuate the fuel pump.
3	Remove ground line of battery.		AR54.10-P-0003LW
4	Remove upper engine cover.
5	Remove engine wiring harness.		AR15.18-P-1000-04LWA
		Do not kink lines, do not subject lines to tension. Otherwise damage will occur.
6	Release shielding (5) in reverse order to tightening procedure and remove.	Tightening procedure for high-pressure pump shielding	AR07.02-P-0815-01MR
7	Remove soundproofing of the high-pressure pump.
8	Clean area around high-pressure pump and high-pressure line (7).	No dirt should be allowed to find its way into the fuel injection system. Failure of the fuel injection system can occur otherwise. Assembly cleaner
			*BR00.45-Z-1028-04A
9	Release fuel pressure in the fuel high-pressure circuit.		AR07.03-P-1460-02MM
10	Remove high-pressure line (7) and seal connections with suitable stop plugs.	Do not kink or bend high-pressure line (7). Leaks can occur otherwise.
		Box wrench bit	Fig 6
		Record plug	Fig 3
11	Unscrew screws (6) in reverse order to tightening procedure.	Rail tightening procedure	AR07.03-P-1010-06MR
12	Remove hold-down tools between rail (8) and fuel injectors (Y76).
13	Mark fuel injectors (Y76) relative to the respective cylinder.	Where fuel injectors (Y76) will be reused Where fuel injectors (Y76) are reused, insert these in cylinder in which they were previously installed. Engine damage will occur otherwise.
14	Detach rail (8) from fuel injectors (Y76) and seal connections with suitable stop plugs.	Ensure utmost cleanliness. Otherwise, leaks and malfunctions occur.
		Record plug	Fig 3
15	Remove fuel injectors (Y76) from cylinder head and seal injector well bores with suitable stop plugs.		AR07.03-P-0004-03MM
		Remove all fuel injectors (Y76), rail (8) may only be installed together with fuel injectors (Y76).
		Puller	Fig 5
		Plug	Fig 2
	Check
16	Check fuel injectors (Y76) for external damage and replace if necessary.	If fuel injectors (Y76) are replaced, install these immediately after removal of transport protective caps. Leaks can occur otherwise.
17	Check high-pressure line (7) for damage and replace if necessary.		AR07.03-P-1010-03MM
		Assembly cleaner	*BR00.45-Z-1028-04A
	Clean
18	Clean fuel connections at fuel injectors (Y76).	Where fuel injectors (Y76) will be reused For cleaning the fuel connections, hold downwards. Otherwise failure of the fuel injectors (Y76).
		Assembly cleaner	*BR00.45-Z-1028-04A
19	Remove stop plugs of injector well bores.	Plug	Fig 2
	Install
20	Replace sealing packages of fuel injectors (Y76) at rail (8).		AR07.03-P-0004-02MM
		Assembly cleaner	*BR00.45-Z-1028-04A
		Drift	Fig 9
21	Replace sealing rings (2, 4) of fuel injectors (Y76).	Where fuel injectors (Y76) will be reused
22	Replace sealing rings (3) of fuel injectors (Y76).	Where fuel injectors (Y76) will be reused
			AR07.03-P-0004-01MM
		Assembly cleaner	*BR00.45-Z-1028-04A
		Assembly tool	Fig 4
23	Remove stop plugs, install fuel injectors (Y76) in rail (8) and secure with hold-down tools.	Where fuel injectors (Y76) are reused, insert these in cylinder in which they were previously installed. Engine damage will occur otherwise. Replace hold-down tools.
		Record plug	Fig 3
24	Remove stop plugs and install rail (8) together with fuel injectors (Y76).	Plug	Fig 2
25	Screw in bolts (6).	Rail tightening procedure	AR07.03-P-1010-06MR
		Screw/bolt, fuel distributor to cylinder head cover	*BA07.52-P-1001-01H
26	Remove stop plugs and install high-pressure line (7).		AR07.03-P-1010-02MR
		Do not kink or bend high-pressure line (7). Leaks can occur otherwise.
		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 6
		Record plug	Fig 3
27	Install soundproofing of the high-pressure pump.
28	Install shielding (5).	Tightening procedure for high-pressure pump shielding	AR07.02-P-0815-01MR
		Bolt for high-pressure pump shielding	*BA07.02-P-1004-01D
		Set of torque tools	Fig 7
29	Install engine wiring harness.		AR15.18-P-1000-04LWA
		M6 X 1	*BA00.10-P-1002-04A
30	Install ground line of battery.		AR54.10-P-0003LW
31	Read out fault memory with vehicle diagnosis system and delete if necessary.
			AD00.00-P-2000-04B
32	Store injector quantity compensation coding in motor control module (MCM).	For installation of new fuel injectors (Y76).
			AD00.00-P-2000-04B
	Check
33	Check fuel high-pressure circuit for leak tightness.		AR07.03-P-1010-04MM
			AD00.00-P-2000-04B
34	Carry out engine test run and check engine for proper operation and leak tightness.
35	Install center and rear lower engine compartment lining.	Vehicles with diagnostic socket	AR61.20-P-1105LW
36	Install upper engine cover.