Opel Astra, Zafira

since 1998 of release

Repair and car operation



Opel Astra
+ Opel Astra and Zafira Cars
+ Operation manual
+ Routine maintenance
- Engine
   Specifications
   Check of kompressionny pressure in cylinders
   Diagnostics of a condition of the engine with use of the vacuum gage
   - Procedures of repair of petrol SOHC engines without their extraction from the car
      Reduction of the piston of the first cylinder in the provision of the top dead point of a step of compression (VMT)
      Removal and installation of a cover of the gas-distributing mechanism
      Removal and installation of a pulley of a cranked shaft
      Removal and installation of a cover of a drive of GRM
      Removal and installation of a belt of a drive of GRM
      Removal and installation of a natyazhitel of a gas-distributing belt and cogwheels of a drive of GRM
      Replacement of an epiploon of a camshaft
      Removal, check of a condition and camshaft installation with the case of the gas-distributing mechanism
      Removal, check of a condition and installation of components of a drive of valves
      Removal and installation of a head of cylinders
      Removal and installation of the pallet of a case
      Removal, service and installation of the oil pump
      Removal, check of a condition and flywheel installation / driving disk
      Replacement of epiploons of a cranked shaft
      Check of a condition and replacement of support of a suspension bracket of the power unit
   + Procedures of repair of petrol DOHC engines without their extraction from the car
   + Procedures of repair of diesel engines of 1.7 l and 2.0 l without their extraction from the car
   + General and major maintenance of the engine
+ Systems of cooling, heating
+ Power supply system and release
+ engine Electric equipment
+ Manual transmission
+ Automatic transmission
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment




Procedures of repair of petrol SOHC engines without their extraction from the car

Reduction of the piston of the first cylinder in the provision of the top dead point of a step of compression (VMT)

General information

The highest point of a piston stroke in the cylinder is called as the top dead point (VMT). Strictly speaking, in 4-тактных engines in the course of rotation of a cranked shaft this situation is reached by each of pistons twice: once at the end of a step of compression and the second — at the end of a final step. At performance of settings of phases of a gazoraspredeleniye and installation of a corner of an advancing of ignition in overwhelming majority of cases the provision VMT of the end of a step of compression of the piston (usually the first cylinder) is used.

Need for piston reduction (it) in situation VMT arises at carrying out many procedures, in particular such, as removal / installation of camshafts, components of a drive of GRM and the ignition distributor.

Some engines are designed in such a manner that at a provorachivaniye cranked or distributive (ых) shaft at removed gas-distributing belts/chains there can be an input of valves in contact with the bottoms of pistons that is fraught with risk of damage of the corresponding internal components, up to destruction of molding of a head of cylinders.

Do not allow change of provision of shaft after belt removal!

Order of performance of procedure


The scheme of an arrangement of adjusting labels of cogwheels distributive (1) and cranked (2) shaft in the provision VMT of the end of a step of compression of the piston of the first cylinder

Reduction of any of pistons in situation VMT is made by a provorachivaniye of a cranked shaft of the engine. If to take a detached view of the engine of a drive of GRM, the direction clockwise will be the normal direction of rotation of a cranked shaft. Remember that attempt of a provorachivaniye of a shaft counter-clockwise can lead to violation of adjustments of phases of a gazoraspredeleniye. The first is the cylinder, extreme GRM from a drive.

 PERFORMANCE ORDER

  1. Disconnect a negative wire of the accumulator. For the purpose of simplification of a provorachivaniye of the engine turn out all spark plugs.
  2. For the purpose of ensuring access to VMT label on a camshaft cogwheel, uncover GRM drive (see. Removal and installation of a cover of a drive of GRM).
  3. By means of the key which has been put on a bolt of fastening of a pulley of a cranked shaft, turn the last in the direction of normal rotation before combination of an adjusting label of a cogwheel of a camshaft with reciprocal risky from above on a back cover of a gas-distributing belt. The label on a rim of a cogwheel of a cranked shaft thus should be combined with a label on the case of the oil pump (see an illustration the Scheme of an arrangement of adjusting labels of cogwheels distributive (1) and cranked (2) shaft in the provision VMT of the end of a step of compression of the piston of the first cylinder).

At performance of the listed conditions the engine will be given in the provision VMT of the end of a step of compression of the piston of the first cylinder.