Mercedes W124

since 1985-1995 of release

Repair and car operation

W124 Mercedes
+ Governing bodies and control devices
+ 2. Maintenance (diesel engines)
+ 4. Repair of 6-cylinder petrol SOHC engines
+ 5. Repair of 6-cylinder petrol DOHC engines
+ 6. Repair of the diesel engine established in the car
- 7. Major maintenance of engines
   7.2. General information
   7.3. Recommendations about engine removal
   7.4. Removal and installation of 4-cylinder petrol engines
   7.5. Removal and installation of 6-cylinder petrol engines
   7.6. Removal and installation of diesel engines
   7.7. Sequence of dismantling of the engine
   - 7.8. Analysis of a head of the block of cylinders
      7.8.2. 6-cylinder petrol SOHC engines
      7.8.3. 6-cylinder petrol DOHC engines
      7.8.4. Diesel engines
      7.8.5. Cleaning and survey of a head of the block of cylinders
      7.8.6. Valves
   + 7.9. Assembly of a head of the block of cylinders
   7.10. Removal of pistons with rods
   7.11. Removal of a cranked shaft
   7.12. Block of cylinders of the engine
   7.13. Pistons and rods
   7.14. Cranked shaft
   7.15. Survey of radical and shatunny bearings
   7.16. Engine balance of assembly at major maintenance
   7.17. Installation of piston rings
   7.18. Installation of a cranked shaft
   7.19. Check of a working gap of radical bearings
   7.20. Installation of a cranked shaft
   + 7.21. Installation of pistons with rods
   7.22. Engine start after major maintenance
+ 10. System of injection of BOSCH CIS-E fuel (KE-JETRONIC)
+ 11. System of injection of BOSCH HFM fuel
+ 12. Fuel system of diesel engines
+ 13. Fuel system of diesel engines
+ 15. System of ignition of 4-cylinder petrol engines
+ 16. System of ignition of four-cylinder petrol engines
+ 19. Mechanical transmission
+ 20. Automatic transmission

7.8.6. Valves


Measurement of diameter of a core of the valve

Grinding in of valves

1. Check a plate of each valve on local corrosion, прожоги, cracks and the general wear. Check a valve core on wear and a bend. Check wear of an end face of a core of the valve. In the presence of any defects the valve is subject to replacement.
2. By a micrometer measure diameter of a core of the valve in several places on length of a core. Any essential distinction in the received data indicates wear of a core of the valve and obligatory replacement of the valve.
3. If valve are in satisfy a telny condition, they should be inserted into the places and are ground in. If plates of valves or a saddle are strongly worn-out, before their grinding in it is necessary to process mechanically or even to replace.
4. Grinding in of valves is carried out as follows. Establish a head of the block of cylinders combustion chambers up on wooden whetstones.
5. Grease with paste for place grinding in a natarelka of the valve and a valve saddle, establish the valve on a place and on a plate of the valve establish a sucker with the holder (handle). Rotating the valve a sucker in different directions, grind in the valve, and it is periodically necessary to raise the valve for redistribution of pritirochny paste.
6. If rough pritirochny paste is used, grinding in to make before emergence of a uniform opaque surface on a saddle of the valve and the valve. Then erase used composition of paste and repeat grinding in process with melkodispersny paste. Grinding in to make before emergence of easy gray and opaque color.
7. Carefully remove traces of pritirochny paste, using the corresponding solvent.

Valve elements

1. Check klapanny springs on damage signs.
2. Establish springs to one of end faces on a bed, check a deviation of an axis of a spring from the vertical plane and length of springs. In case of damage of one of springs it is necessary to replace all springs in a set.
3. Replace maslootrazhatelny caps irrespective of their condition.