Mercedes of the S-class W202

1993-2000 of release

Repair and operation of the car



Mercedes W202
+ 1.2. General information
+ 2. Maintenance
- 3. Engines
   3.1.2. Identification number
   + 3.1.3. Engine
   3.1.4. Cars with the conditioner
   3.1.5. Lower cover of a motor compartment
   3.1.6. Covers of cast openings
   3.1.7. Natyazhitel of a chain
   + 3.1.8. Cover of a head of the block of cylinders
   + 3.1.9. Head of the block of cylinders
   + 3.1.10. Camshafts
   3.1.11. Hydraulic dish-shaped pushers
   3.1.12. Maslootrazhatelny caps
   3.1.13. Valves
   3.1.14. The directing valves
   3.1.15. Saddles of valves in a head of the block of cylinders
   3.1.16. Compression
   + 3.1.17. Maple belt
   3.1.18. Diagnostics of malfunctions (DB)
   3.1.19. General comments
   3.1.20. Repair work without dismantle of the engine
   - 3.1.21. Capital repairs of the engine
      3.1.21.2. Alternatives
      3.1.21.3. Dismantle of the engine
      3.1.21.4. Sequence of dismantling
   + 3.2. Diesel Engine (DE)
   3.2.3. Cars with the conditioner
   3.2.4. Lower cover of a motor compartment
   3.2.5. Covers of cast openings
   3.2.6. Natyazhitel of a chain
   + 3.2.7. Camshaft
   + 3.2.8. Head of the block of cylinders
   + 3.2.9. Maslootrazhatelny caps
   3.2.10. Cover of a head of the block of cylinders (2,2 / 2,5 l)
   3.2.11. Hydraulic dish-shaped pushers
   3.2.12. Valves
   3.2.13. The directing valves
   3.2.14. Saddles of valves in a head of the block of cylinders
   3.2.15. Head of the block of cylinders and motor block
   3.2.16. Compression
   3.2.17. Maple ridge belt
   3.2.18. The pulling device of a maple ridge belt
   3.2.19. Diagnostics of malfunctions (DD)
+ 4. Lubrication system
+ 5. Cooling system
+ 6. Heating, ventilation
+ 7. System of ignition
+ 8. Fuel system
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electrical circuitries






3.1.21. Capital repairs of the engine

3.1.21.1. General comments

GENERAL INFORMATION

It is not always easy to come to a conclusion about expediency of capital repairs of the engine as it is necessary to be based on a number of indicators.

The big run is not a sufficient indicator of need of carrying out capital repairs, on the other hand, the small run does not exclude capital repairs. The most important indicator most likely is timeliness of the current maintenance of the engine. At timely change of oil and the air filter, and also when performing all other necessary works on service, the engine serves reliably throughout many thousands of kilometers of a run. On the contrary, insufficient service can be the reason of sharp reduction of a resource. The raised consumption of oil indicates wear of piston rings or the directing plugs of valves. It is necessary to be convinced that leaks are not the reason of the raised oil consumption, and only after that to draw a conclusion about unfitness of piston rings and guides of plugs. To determine the volume of the forthcoming works, take measurement of a compression in cylinders, or check tightness of the combustion chamber for what it is recommended to address the skilled expert.

If during the operation of the engine the increased noise, or knocks is listened, then wear of connecting or radical rods can be of them a probable cause.

Turn out the regular sensor and measure oil pressure by the manometer, compare the received value with specified in the management. If pressure low, then can be the cause wear of basic bearings or the oil pump.

Loss of power, "failures" in operation of the engine, the increased noise from the gas-distributing mechanism, the increased fuel consumption indicate the need carrying out capital repairs, especially, if all these factors are shown at the same time. If performance of all adjustments does not lead to improvement, then the most expedient means of elimination is repair.

Capital repairs consist in restoration of details of the engine to the state specified in specifications for the new engine. When carrying out capital repairs piston rings are replaced, and walls of cylinders are chiseled to the repair size (or honningutsya).

After repair of cylinders installation of new pistons will be required. Connecting and radical rods are also subject to replacement, if necessary the bent shaft should be proshlifovat before restoration of gaps with connecting and radical rods. As a rule, the valvate mechanism does not change as a state it at the time of repair quite usually satisfactory. During capital repairs of the engine repair of such units as the carburetor, the ignition distributor, a starter and the generator is also carried out. As a result the engine has to have qualities of almost new unit and smoothly serve long time.

Before capital repairs of the engine study the description of the corresponding procedures that there was an impression of the forthcoming amount of works and requirements to them. Capital repairs are simple, however demand big expenses of time. Approximately not less than two weeks, especially are required if for repair and restoration of details (grinding, boring) it is necessary to address in a specialized workshop. Check existence of spare parts and in advance think of acquisition of necessary special tools and the equipment.

Almost all works can be performed by means of standard tool kit though precision measuring instruments will be necessary for check and definition of suitability of these or those details. Often check of a condition of details is carried out in specialized workshops in which receive recommendations about replacement or restoration of details.


Prevention

It is necessary to address in workshops of car service only after full dismantling of the engine and check of all details, especially the block of cylinders to solve what operations on service and repair will be carried out in workshops.


As the condition of the block of cylinders is the defining factor of making decision on its further repair or about purchase of the new repair block of cylinders, it is necessary to buy spare parts or to perform operations on machining of details only after careful check of its technical condition. Make it a rule that the true price of repair is time, then it is not necessary to pay for installation of worn-out or repair details.

In conclusion we will note that assembly of any units should be carried out with all care in the pure room to avoid further failures of the repaired engine.