Contents: Belt ↡ Tensioner ↡
Belt
Petrol models (M112/113)
Installation details of the auxiliary drive belt on gasoline models (M112/113)
1. Remove the fan assembly (1 and 2) (see Chapter Cooling, heating, ventilation and air conditioning systems).
2. Turn the pin (4) of the tension roller (5) counterclockwise, loosen the belt (3) and lock the roller using a rod with a diameter of 5 mm.
3. Remove the belt and carefully examine its condition (see Chapter Routine care and maintenance). Replace if necessary.
4. Installation is carried out in the reverse order - start seating the belt from the tension roller and proceed in the order of the numbers shown in the illustration. Do not forget to adjust the belt tension force (see Chapter Routine care and maintenance).
Laying diagram and installation procedure for the 6-rib belt for the auxiliary drive units of M112/113 engines on pulleys
Top - Models without K/V; Below - Models with K/V; 1 - Crankshaft pulley; 2 - Guide pulley 2/compressor pulley K/V; 3 - Steering pump pulley; 4 - Guide pulley; 5 - Generator pulley; 6 - Pulley of water pump and cooling system fan; 7 - Tension roller
Diesel models
M612
Installation details of the auxiliary drive belt on diesel models equipped with the M612 engine
3 - Tension roller
1. Remove the viscous coupling of the cooling system fan drive (see Chapter Cooling, heating, ventilation and air conditioning systems).
2. Turn the tensioner (2) and lock it with the pin (4), loosen and then remove the drive belt (1).
3. Examine the condition of the belt (see Chapter Routine care and maintenance), replace it if necessary.
4. Installation is carried out in the reverse order - start installing the belt from the tension roller (see illustration below). Do not forget to adjust the belt tension (see Chapter Routine care and maintenance).
M612 Engine Auxiliary Drive Belt Routing Diagram
1 - Crankshaft pulley; 2 - Tension roller; 3 - Pulley of water pump and cooling system fan; 4 - Generator pulley; 5 - Guide pulleys; 6 - Steering pump pulley; 7 - Compressor pulley K/V
M628
Installation details of the auxiliary drive belt on diesel models equipped with the M628 engine
1. Remove the cooling fan shroud (see Chapter Cooling, heating, ventilation and air conditioning systems).
[Material taken from a web resource MERCEDESMAN.ru]
2. Install the air conditioning radiator/condenser protection screen (a metal or plastic sheet measuring approximately 400x680x1 mm).
3. Remove the turbocharger intercooler (Intercooler) (See Chapter Fuel and exhaust systems).
4. Turn the tensioner (2) clockwise, loosen the belt (1) and remove it from the engine.
5. Examine the condition of the belt (see Chapter Routine care and maintenance), replace it if necessary.
6. Installation is carried out in the reverse order - start installing the belt from the tension roller (see illustration below). Do not forget to adjust the belt tension (see Chapter Routine care and maintenance).
M612 Engine Auxiliary Drive Belt Routing Diagram
1 - Crankshaft pulley; 2 - Compressor pulley K/V; 3 - Steering pump pulley; 4 - Guide pulley; 5 - Generator pulley; 6 - Water pump pulley; 7 - Intermediate roller
Tensioner
Petrol models (M112/113)
Installation details of the automatic tensioner of the auxiliary drive belt on gasoline models (M112/113)
1. Remove the drive belt (3) (see above).
2. Turn the tension roller (4a) counterclockwise and secure it with a 5 mm diameter rod.
3. After unscrewing the self-tapping mounting screws, remove the tensioner (4) from the timing belt drive cover.
4. Installation is carried out in reverse order.
Diesel models
M612
Installation details of the automatic tensioner of the auxiliary drive belt of the M612 engine
1. Remove the drive belt (see above).
2. After unscrewing the fastening bolt, remove the tension roller (4) from the tensioner assembly (5).
3. Remove the pin (2) securing the tensioner (5) and, after unscrewing the mounting bolts, remove the latter from the timing belt drive cover.
4. Installation is carried out in reverse order.
M628
Installation details of the automatic tensioner of the auxiliary drive belt of the M628 engine
1. Remove the turbocharger intercooler (Intercooler) (1) (See Chapter Fuel and exhaust systems).
2. Remove the drive belt (2) (see above).
3. Loosen the mounting screws (4) - the screw will be accessible through the recess in the pulley (5) when the engine is turned in the normal direction - and remove the tensioner (3).
4. Installation is carried out in reverse order.