Repair and service Audi A8 in body D2 with 1994 for 1999 of release.
1. Car operation
2. Maintenance service
3. Petrol engines of 2,8 l
3.1. The general data
3.2. Removal and engine installation
3.3. A poliklinovoj belt
3.4. Гаситель fluctuations
3.5. Replacement of a gear belt
3.6. A two-mass flywheel
3.7. A frictional overlay
3.8. The gauge of frequency of rotation of the engine
3.9. A cranked shaft
3.10. Pistons and rods
3.11. An inlet collector
3.12. The left cover of a head of the block of cylinders
3.13. The right cover of a head of the block of cylinders
3.14. A head of the block of cylinders
3.15. A camshaft
3.16. Check of hydraulic pushers of valves
4. Petrol engines of 3,7 and 4,2 l
5. Diesel engines of 2,5 l
6. Diesel engines of 3,3 l
7. Systems of ignition and injection of fuel of petrol engines
8. System of release of the fulfilled gases of cars with petrol engines
9. The power supply system of diesel engines
10. System of prestarting heating of diesel engines
11. System of release of the fulfilled gases of cars with diesel engines
12. Greasing system
13. Cooling system
14. Coupling
15. A transmission
16. Shaft of a drive of forward wheels
17. Features of a design of transmission of all-wheel drive cars
18. A suspension bracket
19. Wheels and tyres
20. A steering
21. Brake system
22. A body
23. Heating and air-conditioning system
24. An electric equipment
25. Electric schemes
 










3-14-golovka-bloka-cilindrov.html

3.14. A head of the block of cylinders

Removal of a head of the block of cylinders spend on the cold engine.
The burnt through or defective lining of a head of the block of cylinders is defined to following signs:
– Decrease in capacity of the engine;
– Decrease in level of a cooling liquid – leaves an exhaust pipe white steam;
– Decrease in level of engine oil;
– Presence in engine oil of a cooling liquid: oil gets grey colour and foams. Thus oil level raises;
– Engine oil presence in a cooling liquid;
– Intensive allocation of vials from a cooling liquid;
– Compression reduction in two next cylinders of the engine.

Preventions
At installation of a head of the block it is necessary to use new bolts of fastening.
All clips and collars which at removal will be damaged or cut, at installation of a head of the block it is necessary to replace with the new.
At installation of a new head with the established camshafts of a surface of contact between cams of a camshaft and pushers of valves it is necessary to grease with engine oil.
Plastic caps for protection of open valves cannot be removed before installation of a head of the block.
At replacement of a head of the block in cooling system it is necessary to fill in a fresh cooling liquid.
Before removal of a head of the block of cylinders be convinced that all hoses, pipelines and electric sockets are disconnected from it.

The left head of the block of cylinders
Removal
Establish the piston of the first cylinder in ВМТ.
Be convinced that the engine cold. Otherwise allow to it to cool down.
Switch off ignition and disconnect a wire of "weight" from the storage battery.
Merge cooling liquid.
Remove the left reception exhaust pipe.
Remove a gear belt from pulleys.
Remove a back casing of a gear belt.
Turn away a bolt of fastening of an arm of a pipe of the amplifier of a steering.
Mark high-voltage wires in figures, remove them from spark plugs of 4-6 cylinders and take aside.
Loosen the a collar, remove a hose from a pipe of system of cooling and turn out a bolt of fastening of a pipe.
Turn out bolts of fastening of a flange of a pipe of system of cooling to a back part of a head of the block of cylinders, supporting a pipe.
Disconnect from a head of the block of cylinders all electric sockets and take them aside.

Fig. 3.1–82. An arrangement of bolts of fastening of the left cover of a head of the block of cylinders



Turn out bolts and uncover heads of the block of cylinders (fig. 3.1–82 see).
Remove маслоотражатель.

Fig. 3.1–84. Sequence of a tightening of bolts of fastening of the left and right heads of the block of cylinders



In sequence, return to a tightening, gradually loosen the, and then turn out completely bolts of fastening of a head of the block of cylinders (fig. 3.1–84).
Remove a head of the block of cylinders and establish it on the soft basis.

Preparation of the left head for installation
Privalochnye surfaces of a head and the block of cylinders should be absolutely pure. For their clearing use a firm plastic or wooden scraper. At clearing be careful, as the aluminium alloy is very easy for damaging. Be convinced that the deposit has not got to channels of system of greasing and cooling. It is especially important for greasing system as the deposit can block oil giving to engine details. If necessary clean channels.
Check up привалочные surfaces of a head and the block of cylinders: on them there should not be notches, deep scratches and other damages. Small defects can be eliminated machining. At detail major defects are subject to replacement.
Using a metal ruler and probe, check up planeness при