Mercedes W124

since 1985-1995 of release

Repair and car operation


W124 Mercedes
+ Governing bodies and control devices
+ MAINTENANCE
+ 2. Maintenance (diesel engines)
+ ENGINE
+ 4. Repair of 6-cylinder petrol SOHC engines
- 5. Repair of 6-cylinder petrol DOHC engines
   5.2. General information
   5.3. Repair operations on the engine established in the car
   5.4. Check of pressure of compression
   5.5. Top dead point (VMT) of the piston of the first cylinder
   5.6. Cover of a head of the block of cylinders
   5.7. Pulley cranked shaft / quencher of krutilny fluctuations and nave
   + 5.8. Covers of a driving chain
   5.9. Check and replacement of a driving chain
   + 5.10. Mechanism of a tension of a driving chain, asterisk and uspokoitel of a chain
   5.11. Boot of the mechanism of a tension
   5.12. Mechanism of adjustment of a camshaft
   5.13. Camshafts and pushers
   5.14. Check and adjustment of provision of camshafts
   5.15. Head of the block of cylinders
   5.16. Oil pallet
   5.17. Oil pump chain and drive
   5.18. Drive flywheel / plate
   5.19. Replacement of sealing rings
   5.20. Bearing replacement in an end face of a cranked shaft
   5.21. Check and replacement of a support of the power unit
   5.22. Oil radiator
+ 6. Repair of the diesel engine established in the car
+ 7. Major maintenance of engines
+ COOLING SYSTEM
+ FUEL SYSTEM
+ 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
+ SYSTEMS OF START, IGNITION
+ 15. System of ignition of 4-cylinder petrol engines
+ 16. System of ignition of four-cylinder petrol engines
+ PRESTARTING HEATING
+ TRANSMISSION
+ 19. Mechanical transmission
+ 20. Automatic transmission
+ POWER SHAFTS
+ BRAKE SYSTEM
+ SUSPENSION BRACKET
+ BODY
+ ELECTRIC EQUIPMENT
+ CHECK OF MALFUNCTIONS





5.15. Head of the block of cylinders
GENERAL INFORMATION
Prevention

For removal of a head of the block of cylinders it is necessary to use the load-lifting mechanism. At installation of a head of the block of cylinders it is necessary to use new laying of a head and a new bolt of fastening of the bearing of the camshaft operating inlet valves.

Unscrewing of bolts of fastening of a head of the block of cylinders

Removal

Vvinchivaniye of an additional bolt in the top adjusting pin of an uspokoitel of a chain

Use of an inertial hammer for extraction of the top pin of an uspokoitel of a chain

Removal of an intermediate asterisk of a driving chain

Removal of the bearing from the forward party of a camshaft

Removal of a driving chain from asterisks of camshafts

Detachment of the electric socket from a fuel nozzle

Detachment of the electric socket from the sensor of temperature of cooling liquid on the engine of 3,0 l

Removal of the tire of grounding from an inlet collector of the engine of 3,0 l

Arrangement of an arm of a plait of wires on an inlet collector of the engine of 3,0 l

Detachment of vacuum hoses from an inlet collector

Arrangement of an air pipe on a head of the block of cylinders

Arrangement of an arm of fastening of the air valve

Unscrewing топливопровода from a pressure regulator on the engine of 3,0 l

Unscrewing of an arm of fastening of a pipe for щупа measurements of level of oil

Unscrewing of a bolt of fastening of a pipe for щупа measurements of level of oil in an automatic transmission

Arrangement of bolts of fastening of an arm of support of an inlet collector

And – bolts of fastening of an arm;

B–bolts of fastening of a pipe

Arrangement of a hose of ventilation of a case of the engine

Removal of a head of the block of cylinders from the engine

PERFORMANCE ORDER
1. Removal of a head of the block of cylinders make on the cold engine. The head of the block of cylinders acts in film together with inlet and final collectors.
2. Remove a weight wire from the accumulator.
3. Open a cowl and establish it in vertical situation.
4. Merge cooling liquid and remove a radiator.
5. Disconnect a hose of supply of cooling liquid from the back left side of a head of the block of cylinders.
6. Establish the piston of the first cylinder in VMT and check that all adjusting labels are combined with indexes.
7. Remove the top cover of a driving chain.
8. Put combination labels on links of a driving chain and an asterisk.
9. Screw in an additional bolt in the top adjusting pin of an uspokoitel of a chain (see Vvinchivaniye's fig. of an additional bolt in the top adjusting pin of an uspokoitel of a chain).
10. Using an inertial hammer and an adapter, for an additional bolt take the top adjusting pin of an uspokoitel of a chain (see fig. Use of an inertial hammer for extraction of the top pin of an uspokoitel of a chain).
11. On engines of 3,0 l unscrew a bolt with the left carving and remove an intermediate asterisk of a driving chain (see fig. Removal of an intermediate asterisk of a driving chain).
12. From the forward party of the camshaft operating inlet valves, holding the bearing from a provorachivaniye, unscrew a bolt and remove the bearing (see fig. Removal of the bearing from the forward party of a camshaft).
13. Remove a driving chain from asterisks of camshafts and, using a soft wire, fix it from falling in a cover (see fig. Removal of a driving chain from asterisks of camshafts).
14. Disconnect from a head of the block of cylinders all electric sockets. Unscrew a bolt of fastening of an arm of a plait of wires to a collector and move a plait of wires aside (see fig. A detachment of the electric socket from a fuel nozzle, the Detachment of the electric socket from the sensor of temperature of cooling liquid on the engine of 3,0 l, Removal of the tire of grounding from an inlet collector of the engine of 3,0 l, the Arrangement of an arm of a plait of wires on an inlet collector of the engine of 3,0 l).
15. Disconnect draft of a control system in the speed of movement.
16. Note an arrangement and disconnect all vacuum hoses from an inlet collector (see fig. A detachment of vacuum hoses from an inlet collector).
17. Disconnect a reception exhaust pipe from a final collector.
18. Disconnect an air pipe from a head of the block of cylinders (see fig. An arrangement of an air pipe on a head of the block of cylinders).
19. Unscrew an arm of fastening of the air valve and remove it together with a pipe from the engine (see fig. Arrangement of an arm of fastening of the air valve).
20. Remove pressure in fuel system and unscrew submitting and returnable топливопроводы (see fig. Unscrewing топливопровода from a pressure regulator on the engine of 3,0 l).
21. Unscrew a bolt, pipes fixing an arm for щупа measurements of level of oil. Take щуп and remove a pipe from the block of cylinders (see fig. Unscrewing of an arm of fastening of a pipe for щупа measurements of level of oil).
22. Disconnect an accelerator cable from the butterfly valve lever.
23. On models with an automatic transmission disconnect a cable of management of pressure from draft of a butterfly valve.
24. On models with an automatic transmission, unscrew bolts of fastening of a pipe щупа measurements of level of oil in a transmission from a back part of a head of the block of cylinders (see fig. Unscrewing of a bolt of fastening of a pipe for щупа measurements of level of oil in an automatic transmission).
25. Unscrew and remove two arms of support of an inlet collector (see fig. Arrangement of bolts of fastening of an arm of support of an inlet collector).
26. From a reverse side of an inlet collector remove a clip of fastening of a vacuum hose and a plait of wires.
27. Weaken a collar and remove a hose of ventilation of a case from a casing сапуна under an inlet collector (see fig. Arrangement of a hose of ventilation of a case of the engine).
28. Weaken a collar and remove a hose of supply of cooling liquid from a cranked branch pipe on the forward party of the engine.
29. Check that all hoses and электричес cues sockets are disconnected from a head of the block of cylinders.
30. Evenly and gradually weaken and unscrew bolts of fastening of a head of the block of cylinders in sequence, return, shown in drawing the Arrangement of a hose of ventilation of a case of the engine.
31. Screw a forward eye for engine lifting on a head of the block of cylinders.
32. Using the load-lifting mechanism, remove a head of the block of cylinders (see fig. Removal of a head of the block of cylinders from the engine).
33. Remove laying of a head of the block of cylinders.

Preparation for installation

PERFORMANCE ORDER
1. Interfaced surfaces of a head and the block of cylinders of the engine are necessary for clearing carefully of the laying and deposit remains, using a plastic or wooden scraper. It is also necessary to clear the top parts of pistons. When cleaning exclude possibility of hit of products of cleaning to oil canals of system of cooling. Carefully clear internal surfaces of cylinders.
2. Check surfaces of interface of a head and the block of cylinders of the engine on existence of defects. Insignificant damages are eliminated with machining. Also, using металличес I forge a ruler and щуп, check planeness of interfaced surfaces.
3. Clear openings under bolts in the block. Bolt screwing up in the opening filled with oil can break off the block because of hydraulic pressure.
4. Measure length of bolts of fastening of a head of the block of cylinders (see fig. Preparation for installation). If the length of a bolt exceeds admissible limits, replace bolts in a set.

Installation

Sequence of a tightening of bolts of fastening of a head of the block of cylinders of the 6-cylinder DOHC engine

PERFORMANCE ORDER
1. Check that adjusting labels of cranked and distributive shaft are combined with indexes.
2. Establish laying of a head of the block of cylinders on directing pins of the block of cylinders.
3. Establish two bolts of back fastening of a head of the block of cylinders.
4. Using the load-lifting mechanism, establish a head of the block of cylinders on the engine.
5. Unscrew bolts and remove a forward eye for engine lifting from a head of the block of cylinders.
6. Grease bolts of fastening of a head of the block of cylinders with engine oil and, being careful, insert them into nests. Screw up bolts of fastening of a head by hand.
7. In the sequence shown in drawing Sequence of a tightening of bolts of fastening of a head of the block of cylinders of the 6-cylinder DOHC engine, tighten bolts of fastening of a head of the block of cylinders in some stages.
8. Further installation is made in sequence, return to removal. Fill in cooling liquid in cooling system.