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

ENGINE 157, 278 in MODEL 166 

ENGINE 157, 278 in MODEL 292 

Shown on engine 278 

Courtesy of MERCEDES-BENZ USA

Shown on engine 278 

Courtesy of MERCEDES-BENZ USA

Courtesy of MERCEDES-BENZ USA

Shown on engine 157 

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
	General information on work on gasoline direct injection system		AH07.00-P-2000-01A
	Remove/install
1	Remove both air filter housings
2	Remove ME-SFI [ME] control unit (N3/10)		AR07.08-P-7008MLJ
3	Remove insulation on rails
4	Remove right and left engine compartment partition wall
5	Remove vent line (8) and boot (9)	The vent line (8) and boot (9) not  must not be separated from each other.
6	Detach engine wiring harness on intake manifold and cylinder head covers		AR01.00-P-2410-02MLJ
7	Unclip purge line (12) at cable duct (13) and unscrew from cylinder head cover
8	Disconnect vacuum line (14) for boost pressure control pressure transducer (Y77/1) and unclip on charge air distributor
9	Disconnect electrical connections on right quantity control valve (Y94/2) and pressure sensor downstream of throttle valve actuator (B287)
10	Detach wiring harness from crash plate (10)
11	Unscrew screw/bolts (10a) and remove crash plate (10)	Bolt, shield to housing for high-pressure pump drive/bracket	*BA07.02-P-1003-01C
12	Remove insulation (11) on high-pressure pumps (1l, 1r)
13	Remove lower engine compartment paneling		AR61.30-P-1001GQ
14	Rotate engine at crankshaft center bolt in direction of engine rotation to a 40° crank angle (CKA) after top dead center (TDC) on cylinder 1 (ignition TDC)		AR05.10-P-7620-04MM
15	Relieve fuel pressure over diagnostic socket	Open tank filler cap for a short time in order to remove the overpressure in the fuel tank.	AR07.03-P-1460-01VA
		Protective cap on service valve	*BA07.03-P-1007-01E
		Pressure hose	Figure
16	Remove high-pressure lines which are mounted on the high-pressure pump (1l, 1r)	Do not kink or bend high-pressure lines. Do this to avoid leaks and damage. The sealing cone for high-pressure lines must be checked before assembly. The work instructions absolutely must be observed for assembly work. Checking of fuel high-pressure circuit must be carried out after assembly: ↓ Check high-pressure lines	AR07.03-P-1010-03MM
		Mount high-pressure lines.	AR07.03-P-1010-02MMB
		Check fuel high pressure circuit.	AR07.03-P-1010-04MM
		Union nut, fuel line to fuel distributor	*BA07.03-P-1001-01E
		Union nut, fuel line to high-pressure pump	*BA07.03-P-1002-01E
		Bolt, fuel line service valve to cylinder head cover	*BA07.03-P-1003-01E
		Bolt, right bracket for fuel line clamp to high pressure pump drive housing/cylinder head	*BA07.03-P-1004-01E
		Bolt, left bracket for high pressure line clamp to cylinder head cover/cylinder crankcase	*BA07.03-P-1005-01E
		Bolt, fuel line clamp to charge air distribution line	*BA07.03-P-1006-01E
		Assembly cleaner	*BR00.45-Z-1028-04A
17	Remove screw/bolts (1s) for high-pressure pump (1l) or (1r)	The high-pressure pump (1l) or (1r) must lie flat on the high pressure pump housing (2) after tightening the screw/bolts (1s) under the screw/bolts (1s). Bolt, high-pressure pump to high-pressure pump drive housing	*BA07.02-P-1001-01C
		Screw/bolts (1s) must be screwed in and out by half a revolution alternately for removal or installation of the high-pressure pump (1l) or high-pressure pump (1r). ↓ Damage can occur to the high-pressure pump (1l) or high-pressure pump (1r) otherwise.
18	Lift high-pressure pump (1l) somewhat and disconnect electrical connection at left quantity control valve (Y94/1)
19	Remove high-pressure pump (1l) or high-pressure pump (1r)	Clean mount of the high-pressure pump (1l) or high-pressure pump (1r). Replace sealing ring (3). There are two variants of the sealing rings (3) which can be differentiated between based on their color. Dry green sealing ring (3) coated with low-friction paint and insert the black sealing ring (3) wet with oil into the high pressure pump housing (2). ↓ Leakage can occur otherwise.
20	Pull tappet elements (4) out of the high-pressure pump housing (2)	The tappet elements (4) must be installed in such a way that the drive rollers for the tappet elements (4) sit on the camshaft. ↓ Damage can occur to the camshaft otherwise.
21	Remove centrifuge vacuum line (7) on intake manifold	When removing the high-pressure pump housing (2).
22	Check tappet elements (4) for wear and damage	Tappet elements (4) damaged ↓ Replace tappet elements (4)
23	Remove bracket for high-pressure pump housing (2) on cylinder head cover	When removing the high-pressure pump housing (2).
24	Remove screw/bolts (2a) for high-pressure pump housing (2)	When removing the high-pressure pump housing (2). Tightening procedure for housing of fuel system high pressure pump	AR07.02-P-1020-02MM
		Observe assembly specification and tightening sequence. Damage can occur otherwise to the camshaft and cylinder head.
		Bolt, high-pressure pump drive housing to cylinder head/cylinder head cover	*BA07.02-P-1002-01C
25	Take out high-pressure pump housing (2) upwards	When removing the high-pressure pump housing (2). Replace seals (5, 6).
26	Install in the reverse order
27	Switch on ignition	The ignition must be switched on for 5 s before the engine start in order to fill the high-pressure pump (1l, 1r) with fuel. Damage can occur to the high-pressure pumps (1r, 1l) otherwise.
	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
28	Perform an engine test run and check fuel system for proper operation and leaktightness		AR07.03-P-1010-04MM

Fig 1: Identifying Pressure Hose (119 589 04 63 00)

Courtesy of MERCEDES-BENZ USA