Remove/install belt drive components - AR13.20-P-0001MRA

Engine 274 in model 205 (except 205.047/147/247), 253 (except 253.954) 

Shown on engine 274.9 with code (494) USA version 

Fig 1: Identifying Belt Drive Remove/Install Components - Shown On Engine 274.9

Courtesy of MERCEDES-BENZ USA

Shown on engine 274.9 with code 494 (USA version) 

Fig 2: Identifying Belt Drive Remove/Install Components - Shown On Engine 274.9

Courtesy of MERCEDES-BENZ USA

	Risk of injury.  Moving parts can pinch, crush or, in extreme cases even sever extremities.	No parts of the body or limbs should be within the operating range of the mechanism when moving components.	AS00.00-Z-0009-01A
	Remove/install
1	Remove upper engine cover
2	Remove engine air intake duct upstream of air filter
3	Loosen poly-V belt (1) and remove	Routing diagram for poly-V belt After assembly of the poly-V belt (1) the clamping device (4) must be pressed onto the multiple teeth unit (3) with a torque of 55 Nm clockwise. Noises and damage on the belt drive can occur otherwise. Do not use belt wax or similar products. This leads to slipping of the poly-V belt (1). To do so, swivel tensioning device (4) at serration (3) counterclockwise, remove poly-V belt (1) and detension tensioning device (4). When laying on poly-V belt (1), the routing diagram must be observed.	AR13.22-P-3902-02MR
4	Remove screw/bolt (5) and remove clamping device (4)	Bolt, tensioning device to crankcase	*BA13.25-P-1003-01Z
5	Remove screw/bolt and remove guide pulley	Engine 274 in model 205 (except 205.047/147/247), 253 (except 253.954) with code 494 (US version)
		Bolt, guide pulley to alternator	*BA13.25-P-1004-01Z
	Check
6	Check components of belt drive for damage, wear and soiling; replace if necessary
7	Install in the reverse order
	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
8	Carry out an engine test run