Mercedes S-Class W-140

1991-1999 of release

Repair and car operation

Mercedes S-Class
+ Mercedes-Benz Cars of a class S (W-140)
+ Operation manual
+ Routine maintenance
- Engine
   Compression check in engine cylinders
   Engine check by means of the vacuum gage
   Belt of a streaming drive of auxiliary units
   + 6-cylinder petrol engines (M104.944 and M104.990/994)
   - 8-cylinder petrol engines (M119.970/981 and M119.971/981)
      Covers of heads of the block of cylinders - installation details
      Removal and installation of the inlet pipeline
      Removal and installation of a final collector
      Removal and installation of heads of the block of cylinders
      Removal and installation of covers of a chain of a drive of GRM
      Replacement of a chain of a drive of GRM
      Check of phases of a gazoraspredeleniye
      GRM drive - the general information, service of components
      Removal and installation of a regulator of phases of a gazoraspredeleniye
      Removal and installation of camshafts
      Check and adjustment of control provision of camshafts
      Removal and installation of valves
      Replacement of directing plugs of valves
      Replacement of rings of saddles of valves
      Removal and installation of pistons
      Designation and sizes of pistons
      Check of a condition of rods
      Check of a condition of a cranked shaft
   + 12-cylinder petrol engines (M120.980/982)
   + 6-cylinder diesel engines (OM603.971)
   + 6-cylinder diesel engines (OM606.961)
+ Systems of cooling, heating
+ Power supply system and release
+ engine Electric equipment
+ gear shifting Box
+ Avtomaticheckaya transmission
+ Coupling
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment


Removal and installation of pistons



1. Unscrew shatunny covers and remove pistons together with rods.
2. Check bolts of fastening of shatunny covers.
3. By means of a screw-driver remove a lock ring and выпрессуйте a piston finger.



1. If the piston is damaged, check a gap and axial palpation of piston rings.
2. Oil a piston finger and plugs of rods.
3. Establish the piston so that the arrow was directed in the direction of movement and blocking grooves (shooters) of a rod settled down outside.
4. Press a piston finger in the piston by hand.
5. Insert a lock ring into a flute.
6. Establish a tape for a staving of piston rings, and insert the piston into the cylinder shooters in the movement direction.
7. Establish shatunny covers on rods on designations on them.
8. Turn a cranked shaft and check ease of rotation.

Technical parameters

Piston gap
0.004-0.026 mm
Difference between mass of the piston of each cylinder
8 g
Length of a piston finger
24.000 mm
Gap of landing of a piston finger in the piston
0.004-0.008 mm