Remove/install integrated starter alternator - AR15.40-P-0003SXH

ENGINE 272.974 in MODEL 221.095/195 

Fig 1: Identifying Integrated Starter Alternator Remove/Install Components (1 Of 2)

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying Integrated Starter Alternator Remove/Install Components (2 Of 2)

Courtesy of MERCEDES-BENZ USA

	Risk of death  when touching components on vehicles with high-voltage on-board electrical system	Do not touch components and open lines of the high-voltage on-board electrical system. Persons who wear electronic implants (e.g. cardiac pacemakers), must not  carry out any work on high-voltage on-board electrical systems.	AS54.00-Z-0001-01A
	Note on the voltage on-board electrical system		AH54.00-P-0010-01A
	Evaluation of high-voltage components		AH54.00-P-6500-01SXH
	Information on preventing damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
	Remove/install
1	Perform enable for the high voltage on-board electrical system		AR54.10-P-1150SXH
		After completing the work, attach initial startup event log together with the power disable event log to the vehicle file.
2	Remove transmission	MODEL 221.0/1 with ENGINE 272.974 with TRANSMISSION 722.9 Without 4MATIC	AR27.10-P-0500SX
3	Remove O2 left sensor downstream of catalytic converter		AR07.52-P-5303SX
4	Detach both coolant hoses from the power electronics control unit		AR08.10-P-0011SXH
		Detach the front coolant hose first to avoid causing damage to the power electronics control unit.
5	Detach power electronics control unit from the cylinder crankcase (12) and set aside with attached electrical lines		AR08.10-P-0011SXH
		The high-voltage lines must not be detached from the power electronics control unit. Non-observance of this leads to destruction of the power electronics control unit. The power electronics control unit must be replaced in case of damage to the high-voltage lines.
6	Disconnect electrical connection at crankshaft Hall sensor and lay outside the working area		AR15.12-P-2133SX
7	Disconnect electrical connection at rotor position sensor and lay outside the working area		AR15.12-P-2139SXH
8	Remove screw/bolts (4, 6) and intermediate housing (5)	Remove screws/bolts (4, 6) carefully The 3-phase line connecting point (7) can be damaged otherwise.
		Screw/bolt, intermediate housing to crankcase/oil pan	*BA01.40-P-1013-01G
9	Bring integrated starter alternator (A79) into assembly position	To do this turn engine at the center bolt of the crankshaft in direction of engine rotation until the dowel pin (2) is in the 12 o'clock position as shown.
10	Loosen screw/bolts (9) from stator on cylinder crankcase (12); do not remove completely	Bolt, stator to crankcase	*BA08.10-P-1001-01A
11	Loosen screw/bolts (3) from rotor on crankshaft; do not remove completely	Bolt, starter ring gear/starter-alternator to crankshaft	*BA03.30-P-1004-01M
12	Fix integrated starter alternator (A79) with fit bolts M8 (1P) into the assembly position	The fit bolts M8 (1P) must  be tightened in 2 stages. After tightening the heads of the fit bolts M8 (1P) lie do not  lie on the integrated starter alternator (A79).
		Fit bolt on starter-alternator	*BA08.10-P-1002-01A
		Removal and installation tool	Fig 3
13	Screw assembly bolts M6 (1M) into the integrated starter alternator (A79), lay on by hand and tighten down in 2 stages	The assembly bolts M6 (1M) must  be tightened in 2 stages.
		Assembly bolts on starter-alternator	*BA08.10-P-1003-01A
		Removal and installation tool	Fig 3
14	Remove two opposing screw/bolts (3) for the rotor on crankshaft and screw in assembly bolts by hand	Removal and installation tool	Fig 3
15	Remove screw/bolts (3) from rotor on crankshaft
16	Remove screw/bolts (9)	Lay on screw/bolts (9) by hand.
17	Disconnect electrical plug connection for starter-alternator temperature sensor (8) on integrated starter alternator (A79)
18	Remove integrated starter alternator (A79) downwards	Handle integrated starter alternator (A79) carefully. Cables or CNs can be damaged otherwise Do not bring starter-alternator (A79) into contact with the battery acid. This will be attacked and damaged otherwise. Do not bring the starter-alternator (A79) into contact with the brake fluid, hypoid gear oil and diesel fuel. The surfaces corrosion protection will be damaged otherwise.
	Check
19	Check crankshaft radial sealing ring (11) for leaktightness; replace if necessary		AR03.20-P-3063SXH
20	Check end cover (10) for leaktightness; seal if necessary		AR01.40-P-8913SXH
21	Install in the reverse order
22	Carry out commissioning of the integrated starter alternator(A79) using Star Diagnosis
			AD00.00-P-2000-04A
	Check
	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
23	Carry out an engine test run and check engine for leaktightness and proper operation

ELECTRIC MOTOR

Number	Designation			ENGINE 272.974
BA08.10-P-1003-01A	Assembly bolts on starter-alternator	Stage 1	Nm	5
		Stage 2	Nm	12

ELECTRIC MOTOR

Number	Designation		ENGINE 272.974
BA08.10-P-1001-01A	Bolt, stator to crankcase	Nm	20

ELECTRIC MOTOR

Number	Designation			ENGINE 272.974
BA08.10-P-1002-01A	Fit bolt on starter-alternator	Stage 1	Nm	5
		Stage 2	Nm	12

CYLINDER CRANKCASE, TIMING CASE COVER, END COVER

Number	Designation			ENGINE 272
BA01.40-P-1013-01G	Screw/bolt, intermediate housing to crankcase/oil pan	M6	Nm	8
		M10	Nm	38

FLYWHEEL, DRIVE PLATE, VIBRATION DAMPER, STARTER RING GEAR

Number	Designation			ENGINE 272
BA03.30-P-1004-01M	Bolt, starter ring gear/starter-alternator to crankshaft	Stage 1	Nm	20
		Stage 2	Nm	45
		Stage 3	∠°	90

Fig 3: Identifying Removal And Installation Tool (272 589 06 63 00)

Courtesy of MERCEDES-BENZ USA