The modern high-forced engines impose special requirements to engine oils. Oil should not evaporate, and the oil film — to break at high temperatures of working surfaces of cylinders. Oil has to burn down without the remains, connect soot and dirt that they were not postponed in the engine. For effective fight against deposits in oil system of the engine of oil have to have high flushing properties and the increased wear resistance.

Mercedes for the diesel engines recommends oils of the following brands:

1. CCMC-D4, CCMC-D5 and CCMC-PD2. Brands of API CE oil or CF-4 on qualification of API are used only if on hand there is no oil of the SSMS brands. It is not important whether you filled in oil at the station or bought it, on packing there has to be one of the recommended oil brands.

TECHNICAL DICTIONARY Viscosity. Measure of the expiration of lubricant properties of oil. In the winter engine oil has to be so liquid that right after cold start to grease all necessary knots. In the summer, on the contrary, dense oil that at high temperatures integrity of a film of lubricant was not broken is required.

SAE class (Society of Automotive Engineers). Means a viscosity class, for example SAE 15W-40. The less first, the is less viscous oil on cold ("W" – winter). Oil 0W has lubricant properties at –30 °C, 5W — at –25 °C, and 15W — at –15 °C. The second is higher, the better oil resists to influence of high temperatures.

ACEA (Associacion des Constructeurs Europeen d’Automobiles). The European norm of oil entered in 1996. Replaces norm of SSMS. For petrol engines there are A1 brands (oil with the small content of the purified alcohol), A2 (oil with small amount of additives), A3 (highly effective oil). For diesel engines there are B1, B2 and B3 brands.

SSMS (Comittee des Constructeurs d’Automoboles du Marche Commun). The specification includes the letters "G" (petrol engines) and "PD" (diesel engines), and also number. The this number is higher, the quality of oil is better.

API (American Petroleum Institute). The specification consists of the letters "S" (petrol engines), "With" (diesel engines) and others. The letter is spaced far apart from the beginning of the alphabet, the quality of oil is higher.

2. Oils with marking of CCMC-G4/G5 or API SG are developed for petrol engines therefore they cannot be used for diesel Mercedes engines. But if on packing there is a double marking, for example CCMC-G4/PD2, this oil is suitable for engines of both types.

Fig. 4.32. Scale of working ranges of oils

In the European region, with a big range of winter and summer temperatures, during the whole year it is possible to use oil of a class of viscosity 15W-40 (fig. 4.32) or 10W-40. Only at very low or high temperatures remaining a long time it is necessary to use oil of other viscosity.

Serviceable engines banish through piston rings in an engine case from 50 to 70 l of the fulfilled gases a minute. These gases have to be removed from the engine not to create strong loads of consolidations. It is carried out by ventilation of a case.

Part of oil burns down at lubricant of pistons. Well adjusted engine spends about 0,2 l for 1000 km, Mercedes has the most admissible consumption of oil – 1,5 l on 1000 km.

PRACTICAL ADVICE Big consumption of oil Pay attention to the following circumstances: 1. Before controlling an oil consumption, it is necessary to be convinced that it does not leak from the engine (visual survey of the motor). 2. If the level of oil is higher than the maximum mark in the probe, then the consumption of oil will be always more as its surplus is removed through system of ventilation. 3. Universal oil demands constant check. 4. The sharp manner of driving of the car raises an expense not only fuels, but also oils, especially at the movement on big turns. 5. The oil consumption is always more at a running in of the new car (it is minimum – 5000 km). 6. The engine can be faulty.