Mercedes S-Class W-140

1991-1999 of release

Repair and car operation

Check of levels of liquids, control of leaks

Below procedures of check of level the liquids made through each 400 km of run or weekly are described. The description of other checks of levels of liquid can be found further in the Sections devoted to specific procedures of service. Irrespective of check intervals according to the schedule do not allow, that liquid followed under the car, - similar leaks indicate malfunction which it is necessary to eliminate immediately.

At check of level of any working liquid the car should settle down strictly horizontally!

Liquids are the integral component of systems of greasing, cooling, brake and systems of washing of a windscreen. In view of a gradual expense and/or pollution of liquids in the course of normal operation of the car, it is necessary to replace them periodically. Before starting a liquid dolivaniye in any of the listed components study requirements of Specifications to types and volumes of applied liquids.

Impellent oil

Visual control of leaks

At the greasy engine and a big consumption of oil check places of the most probable development of leaks:

Sealing element of a cover of a jellied mouth, - check on existence on existence of cracks and other mechanical damages;

Components of system of ventilation of a case (in particular - the ventilating hose going from a cover of a head of cylinders to a hose of absorption of air);

Laying of a cover of a head of cylinders;

Laying of a head of cylinders;

Sealing ring of a drain stopper of the pallet of a case of the engine;

Laying of the oil filter, - attentively study a place of a prileganiye of the filter to a flange;

Laying of the pallet of a case.

Forward and back epiploons of a cranked shaft.

Wrap the generator in polyethylene, spray the engine a usual cold cleaner, - then, through short time, - wash out water on a car wash.

Joints of interfaced surfaces and sealing elements of the power unit powder outside with lime or talc.

Check oil level, if necessary add.

During short (about 30 km) trips (it is desirable on the high-speed route) warm up the engine, - the warmed-up oil differs the increased fluidity and easier filters through thinnesses.

Park the car and, highlighting itself a lamp, investigate the engine for the purpose of localization of sources of leakages of oil.

Eliminate the reasons of development of leaks.

Level check

The maximum admissible consumption of impellent oil makes 1L/1000 km, the real consumption level of oil depends on a manner, - frequent movement with high turns of the engine conducts to increase in a consumption of oil.

Information on a principle of functioning of a control lamp of level of impellent oil is provided in the Section the Combination of devices, measuring instruments and control lamps and light indicators of Head the Operation manual

About dangerous falling of level of impellent oil of the driver the control lamp (warns built in assembly of the lock of ignition see. Section Combination of devices, measuring instruments and control lamps and light indicators of Head Operation manual). The sensor switch of level of oil is located under the car, in the right forward corner of the pallet of a case of the engine.

Location of a jellied mouth and щупа measurements of level of impellent oil on the S280 and S320 models


1 — Shchup

Location of a jellied mouth and щупа measurements of level of impellent oil on the S300TDI models


1 — the Mouth 2 — Shchup

Location of a jellied mouth and щупа measurements of level of impellent oil on the S420 and S500 models


1 — Shchup 2 — the Mouth

Location of a jellied mouth and щупа measurements of level of impellent oil on the S600 models


1 — Shchup 2 — the Mouth

Check of level of impellent oil is made by means of measuring щупа, passed in directing tube and lowered in the engine to the bottom point of the pallet of its case. Check of level of oil should be made before the trip first in the present day, or about 5 minutes later after an engine stop. If to execute check immediately after engine switching off, its results will adequately not reflect a situation as the part of oil will appear distributed on internal galleries and engine components.

Take measuring щуп from a directing tube and dry wipe its edge pure rags or a paper towel. Fill щуп back in a tube against the stop, then again take. Having examined an edge щупа, estimate size of the site moistened with oil. Level of oil should be between the top and bottom marks in an edge щупа. In case of need add in the engine the corresponding amount of oil of a demanded grade.

Level lowering out of limits of the bottom border of an admissible range conducts to development of oil starvation of the engine fraught with serious mechanical damages of the last. Try not to pour also oil above the top mark as it can lead to a pelting of spark plugs or failure of epiploons of the power unit as a result of excessive increase of pressure.

To fill in oil in the engine it is necessary to remove the cover of a jellied mouth equipped with a carving. In order to avoid an oil razbryzgivaniye during its filling in the engine use a funnel, or a butterdish with a long nouse. Having filled in oil, screw and strongly tighten a cover of a jellied mouth, then start the engine and attentively examine on existence of signs of leaks a drain stopper and a surface of the oil filter interfaced to the block.

Muffle the engine, wait 5-10 minutes during which oil will merge in the pallet, then once again check its level.

Surplus is necessary for merging or pumping out oil, - excessive level of impellent oil can be at the bottom of failure of the catalytic converter. Track reliability of a tightening of a cover of a jellied mouth.

Check of level of engine oil is important preventive procedure of service of the engine. Continuous decrease in level testifies to existence of leakages of oil as a result of failure of epiploons, damage of sealing laying, wear of piston rings or directing plugs of valves. If oil on color or a consistence reminds milk, or at it there are water drops, it speaks about possible damage of laying of a head of cylinders, or formation of cracks to a head body (ok) or the block. Check should be made immediately. During measurement of level of oil always check also its condition. Big and index fingers remove from an edge щупа oil traces, - in case of presence at it small metal particles oil is subject to replacement (see. Section Replacement of impellent oil and oil filter).

Cooling liquid of the engine

Do not allow antifreeze hit on open sites of a body and the painted surfaces of the car.

Casual splashes immediately wash away a plentiful quantity of water.

Remember that antifreeze is extremely toxic liquid and its hit in an organism even in small amounts is fraught with the most serious consequences, up to a lethal outcome.

Never leave antifreeze being stored in leaky closed container, immediately collect cooling liquid spilled on a floor.

Remember that the sweetish smell of antifreeze can draw to itself attention of children and animals.

About ways utilization of the fulfilled cooling liquid consult with local authorities, - in many regions of the world special points on different reception of working off are equipped.

At all do not merge old cooling liquid in the sewerage and on the earth!

Recently nontoxical grades of antifreeze are developed, nevertheless, they also should to be utilized in the organized order

All cars considered in this Management, are equipped with system of cooling of the compensatory type, working at superfluous pressure. The white plastic broad tank is located in an impellent compartment and connected by a hose to a radiator.

In process of an engine warming up in the course of its work extending cooling liquid fills a tank. When cooling engine cooling liquid automatically arrives back in cooling system that provides maintenance of constant value of its level. About dangerous falling of level of cooling liquid of the driver the control lamp (warns included in structure of a combination of devices see. Section Combination of devices, measuring instruments and control lamps and light indicators of Head Operation manual). The sensor switch of level of cooling liquid is located in the lower part of a broad tank of system of cooling.

Check of level of cooling liquid in the tank should be made regularly, at strictly horizontal position of the car and the switched-off engine. In a cold condition of cooling liquid its level should reach a mark of "MIN" in a broad tank. In a hot condition of cooling liquid level should be higher approximately on 1.5 cm. In case of need make the corresponding adjustment, - add 40 %/60 %-nuyu an antifreeze mix on a basis этиленгликоля with water (see. Specifications).

Banish the car and again measure level of cooling liquid. If to the necessary level it is required to add only small amount of cooling liquid, for this purpose it is possible to use pure water. However frequent additions of water will dilute antifreeze. To provide a normal ratio of antifreeze and water, always add to the necessary level a demanded mix.

If level of cooling liquid falls regularly, in system leak existence is possible. Examine a radiator, hoses, a cover of a jellied mouth, drain jams and the water pump (address to the Section Check of functioning of system of cooling and frost resistance of cooling liquid, liquid replacement). If leaks it is not revealed, make check of tightness of a cover of a broad tank and a radiator in conditions HUNDRED.

If you need to uncover, wait, while the engine completely will cool down, then wrap up a piece of thick rags round a cover and unscrew it to the first emphasis. If thus from under a cover steam or cooling liquid starts to escape, let's to the engine cool down a little more, and only then uncover.

It is necessary to check a condition of cooling liquid also. It should be rather pure. If liquid has brown or rusty color, it it is necessary to merge, wash out system and to fill it with a new mix. Even if cooling liquid looks normally, inhibitors of corrosion entering into its structure lose over time the efficiency therefore it is necessary to replace it through certain periods.

For check of frost resistance of cooling liquid it is necessary to use the areometer.

Brake liquid

Brake liquid can harm your eyes and damage the painted surfaces of the car therefore be extremely careful at the treatment of her. Do not use brake liquid which long time stood opened or to which is more than one has some. Brake liquid has property to absorb moisture from air that can lead to dangerous loss of efficiency of brake system. Use only the recommended type of brake liquid. Mixing of various types of liquid can lead to refusal of brake system.

The main cylinder of brake system is established in a back left corner of an impellent compartment. About falling of level of brake liquid of the driver prevents operation built in a combination of devices of a control lamp (see. The section the Combination of devices, measuring instruments and control lamps and light indicators in Head the Operation manual) which poplavkovy sensor switch is built in a GTTs tank cover.

Level of brake liquid is checked visually, on labels on the plastic tank established on the main cylinder. Level of liquid should be between «MAX» and «MIN» labels. If level is lower admissible, at first wipe top of the tank and a cover pure rags to prevent dirt hit in system after cover removal. Add to the necessary level the recommended liquid, but do not pour.

While the tank cover is removed, check liquid and the tank of the main cylinder on existence of pollution. If at it there are particles of a rust, dirt or a water drop, liquid from system it is necessary to merge and fill in the new.

After tank addition to the necessary level make sure that the cover is established exactly, in order to avoid leakages of liquid and/or dirt hit.

Liquid level in the main cylinder will fall slightly as a result of wear process of frictional overlays of brake shoes. There is no need to add it until level remains near «MIN» label; it will rise after replacement of slips. Very low level can indicate wear of brake shoes. Check them on wear existence (see. Section Check of brake system).

If level of brake liquid constantly falls, immediately check all system on existence of leaks. Survey brake lines, hoses and shtutserny connections, together with supports, wheel cylinders and the main cylinder (address to Sections Check of brake system, Check of a condition and replacement of hoses of an impellent compartment, localization of leaks).

If at check of level of liquid the tank appears is empty or nearly is empty, the brake system should be checked on existence of leaks and is pumped over (address to Heads Coupling and Brake system).

Liquid of system of hydrostrengthening of a wheel (GUR)

If liquid level in the tank fell below a zone corresponding to temperature of liquid, the steering with the hydraulic amplifier of the steering mechanism is necessary for checking in a specialized workshop as liquid loss takes place. In this case it is not enough to be limited only to addition of level of liquid.

Check of level of GUR liquid on the models equipped with engines of a series 104 and 119


30 — the GUR Tank 30с — the Plastic index

Check of level of GUR liquid is made at order temperature 20°С. Level of liquid should be between marks of "MIN" and "MOVE" of the plastic index of the tank / (except the models equipped with engines of a series 120) / an edge of the tank built in in a cover measuring щупа (models with series 120 engines). The full volume of the tank makes 1.4 l.

Information on correction of level of GUR liquid for diesel models at the moment of drawing up of the real Management by producers was not presented, the principle is similar to one of described above for petrol engines.

Liquid of a washer wind glasses/lenses of headlights

The concentrate of stekloomyvayushchy means is easily combustible! At the address with a concentrate of stekloomyvayushchy means application of fire, an open flame and smoking are forbidden.

Liquid for washing of a windscreen contains in the plastic tank in the right forward corner of an impellent compartment. The jellied mouth of the tank is deduced in the panel of a front and is between the right block headlight and a radiator. Capacity of the tank is given in Specifications.

About falling of level of cooling liquid of the driver prevents operation built in a combination of devices of a control lamp (see. Section Combination of devices, measuring instruments and control lamps and light indicators of Head Operation manual). The sensor switch of a control lamp is built in in the top part of the tank of cooling liquid.

In areas with a temperate climate it is possible to fill system with usual water, but it is recommended to add in means water for washing of glasses (the summer concentrate of MV has S marking). The tank should be filled no more than on two thirds that there was a free space on a case of expansion of water when freezing. In areas with cold climatic conditions it is necessary to use a special concentrate for windscreen washing (W marking), reducing a freezing point of liquid which can be got in any shop of automobile accessories. Usually it is on sale in the concentrated or ready look. If you got the concentrated antifreeze, mix it with water according to the instruction of the producer on packing.

Do not use antifreeze of system of cooling - it will damage the painted surfaces of the car!