Remove/Install High-Pressure Pump - AR07.02-P-1020MRA

Engine 274.9 in model 205 

Engine 274.9 in model 253 

Shown on engine 274.9 in model 205 (except 205.047/147/247) 

Courtesy of MERCEDES-BENZ USA

	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
	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
	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 lower engine compartment paneling	For vehicles with a diagnostic socket. Engine 274.9 in model 205 Engine 274.9 in model 253	AR61.20-P-1105LW
2.1	Relieve fuel pressure over diagnostic socket	For vehicles with a diagnostic socket.	AR07.03-P-1460-01MR
		Dust cap on service valve	*BA07.03-P-1003-01F
		Pressure hose	Fig 5
2.2	Relieve fuel pressure over diagnostic system	For vehicles without a diagnostic socket. To do so, select following menu items: Engine management control unit → Actuation → Actuate the fuel pump.	AD00.00-P-2000-04B
3	Disconnect ground line of battery		AR54.10-P-0003LW
4	Remove upper engine cover
5	Remove engine air intake duct upstream of air filter
6	Rotate engine at crankshaft center bolt in direction of engine rotation to a 79°crank angle (CKA) after top dead center (ignition TDC) on cylinder 1	Socket wrench bit	Fig 1
7	Remove cable duct (1) from the cylinder head cover, shielding (2) and oil separator
8	Release and disconnect electrical connection of high-pressure pump (4)
9	Remove shielding (2)	Tightening procedure for high-pressure pump shielding Unfasten shielding (2) counter to the tightening procedure.	AR07.02-P-0815-01MR
10	Remove soundproofing (5)
11	Clean area around high-pressure pump (4) and high-pressure line (6)	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
12	Relieve fuel pressure in fuel system high-pressure circuit		AR07.03-P-1460-02MM
13	Remove low-pressure line from high-pressure pump (4) and close off connections using suitable stop plugs	Record plug	Fig 6
		Pliers for click clamps	Fig 3
14	Remove high-pressure line (6) and seal off connections using suitable stop plugs	Do not kink or bend high-pressure line (6). Otherwise leaks and damage can occur. Record plug	Fig 6
		Box wrench bit	Fig 2
15	Remove screw/bolts (4s)	Remove screw/bolt (4s) alternately respectively by half a revolution. Damage may occur otherwise to the high-pressure pump (4).
16	Take out high-pressure pump (4)
17	Pull tappet element (7) out of the cylinder head cover
	Install
18	Check tappet element (7) for wear and check for damage and replace if necessary
19	Clean mount for high-pressure pump (4) in the cylinder head cover
20	Position tappet element (7) in cylinder head cover	The drive roller of the tappet element (7) must sit on the camshaft. The camshaft can get damaged otherwise.
21	Replace sealing ring of the high-pressure pump (4)
22	Position high-pressure pump (4) in cylinder head cover
23	Tighten new screws/bolts (4)	Screw in screw/bolts (4s) alternately each by half a revolution. Damage may occur otherwise to the high-pressure pump (4). The high-pressure pump (4) must lie flat on the cylinder head cover after tightening the screw/bolts (4s). Otherwise leaks and damage can occur to the high-pressure pump (4). Bolt, high-pressure pump to cylinder head cover	*BA07.02-P-1003-01D
24	Check sealing cone on high-pressure line (6)		AR07.03-P-1010-03MM
		Assembly cleaner	*BR00.45-Z-1028-04A
25	Install high-pressure line (6)		AR07.03-P-1010-02MR
		Union nut, fuel line to high-pressure pump	*BA07.03-P-1002-01F
		Union nut, fuel line to fuel distributor	*BA07.03-P-1001-01F
		Box wrench bit	Fig 2
26	Attach low-pressure line with new clamp on high-pressure pump (4)	Pliers for click clamps	Fig 3
27	Install soundproofing (5)
28	Install shielding (2)	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 4
29	Mount cable duct (1) on the cylinder head cover, shielding (2) and oil separator	M6X1	*BA00.10-P-1002-04A
30	Connect electrical connection of high-pressure pump (4) until it is locked
31	Install engine air intake duct upstream of air filter
32	Connect ground line to battery		AR54.10-P-0003LW
33	Switch on ignition	The ignition must be switched on for 5 s before the engine start in order to fill the high-pressure pump (4) with fuel. Damage may occur otherwise to the high-pressure pump (4).
34	Check fuel high-pressure circuit		AR07.03-P-1010-04MM
			AD00.00-P-2000-04B
	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 buttoned-up and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
35	Perform an engine test run and check engine for proper operation and leaktightness
36	Install center and lower engine compartment paneling	For vehicles with a diagnostic socket. Engine 274.9 in model 205 Engine 274.9 in model 253	AR61.20-P-1105LW
37	Install upper engine cover

Fig 1: Identifying Socket Wrench Bit (001 589 65 09 00)

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying Box Wrench Bit (000 589 80 03 00)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Pliers For Click Clamps (171 589 00 37 00)

Courtesy of MERCEDES-BENZ USA

Fig 4: Identifying Set Of Torque Tools (230 589 00 99 00)

Courtesy of MERCEDES-BENZ USA

Fig 5: Identifying Pressure Hose (119 589 04 63 00)

Courtesy of MERCEDES-BENZ USA

Fig 6: Identifying Record Plug (129 589 00 91 00)

Courtesy of MERCEDES-BENZ USA