Remove/install spark plugs (Engine 156) - AR15.12-P-1010GZS

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ENGINE 156 in MODEL 164, 251

Shown on the right cylinder bank

Fig 1: Identifying Spark Plugs (Shown On Right Cylinder Bank)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

	Remove/install
	Risk of death caused by contact with parts conducting high voltages.	Do not touch parts which conduct high voltages. Persons who wear electronic implants (e.g. heart pacemakers) should never perform any work on the ignition system	AS15.10-Z-0001-01A
	Risk of injury to skin and eyes caused by handling hot or glowing objects.	Wear safety gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
	Notes on avoiding damage to electronic components due to electrostatic discharge	All models	AH54.00-P-0001-01A
	Notes on avoiding damage to ignition system		AH15.10-P-0002-01D
	Risk of injury caused by fingers being pinched or crushed when removing, installing or aligning hoods, doors, trunk lids, tailgates or sliding roof.	Keep body parts and limbs well clear of moving parts.	AS00.00-Z-0011-01A
1	Open engine hood and raise to vertical position	Model 164	AR88.40-P-1000GZ
		Model 251	AR88.40-P-1000RT
2	Remove the partition wall between the wheelhouses	Only model 251.	AR62.30-P-2400RT
3	Remove air filter housing		AR09.10-P-1150GZS
4	Remove ignition coils		AR15.12-P-2003GZS
			*BA15.10-P-1001-04B
5	Remove spark plugs (R4) from cylinder heads		*BA15.10-P-1001-01H
		Spark plug wrench	*WH58.30-Z-1073-06A
6	Install in the reverse order
	Checking
	Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running	Secure vehicle to prevent it from moving by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
7	Carry out engine test run

IGNITION COIL

Number	Designation		Engine 156
BA15.10-P-1001-04B	Bolt, ignition coil to cylinder head cover	Nm	8

SPARK PLUGS

Number	Designation		Engine 156
BA15.10-P-1001-01H	Spark plug to cylinder head	Nm	20

COMMERCIALLY AVAILABLE TOOLS

Number	Designation
WH58.30-Z-1073-06A	Spark plug wrench