Opel Omega

since 1993-1999 release

Repair and operation of the car

Opel Omega
+ 1. Maintenance instruction
+ 2. Maintenance
- 3. Repair of engines
   + 3.1. SOHC engines of 2,0 liters
   + 3.2. DOHC engines of 2,0 liters
   + 3.3. 2,5 and 3,0 liters engines
   - 3.4. Partition of all petrol engines
      3.4.1. Technical characteristics
      3.4.2. Check of a compression
      + 3.4.3. Engine partition
      3.4.4. Auxiliary elements of the engine
      + 3.4.5. Engine
      3.4.6. Engine partition
      3.4.7. Head of cylinders and valves
      3.4.8. Pistons and rods
      3.4.9. Bent shaft
      3.4.10. Block of cylinders
      3.4.11. Radical bearings and bearings of rods
      3.4.12. Piston rings
      3.4.13. The first start of the engine after a partition
   + 3.5. 2,0 liters diesel engine
   + 3.6. 2,5 liters diesel six-cylinder engine
+ 4. Heating system and ventilation
+ 5. Fuel, exhaust systems
+ 6. System of start of the engine
+ 7. System of ignition
+ 8. Coupling
+ 9. Transmissions
+ 10. Main transfer, half shafts
+ 11. Brake system
+ 12. Suspension bracket and steering
+ 13. Body
+ 14. Body electric equipment

3.4.2. Check of a compression

GENERAL INFORMATION

If the engine works badly or with interruptions, check system of ignition and fuel system. If the reasons of bad operation of the engine did not manage to be found, carry out an inspection of a compression. Regular conducting this check will allow you to prevent emergence of malfunctions also in advance.

For conducting check the engine has to be warmed, the accumulator has to be charged, and spark plugs have to be unscrewed.

PERFORMANCE ORDER

1. Disconnect system of ignition, having disconnected a wire of high voltage of the coil of ignition from an ignition distributor cover. Ground a wire on the block of cylinders.

2. Connect the device for measurement of a compression to a N1 cylinder spark plug opening.

3. Completely open a butterfly valve and scroll a bent shaft of the engine a starter. After one or two turns pressure of compression has to increase to the maximum mark, and then be stabilized. Write down the received result.

4. Carry out a similar inspection with other cylinders and write down the received indications.

5. Pressure in all cylinders has to be identical. The difference more than in 2 bars between any two cylinders means malfunction. In the serviceable engine pressure has to increase quickly. The small pressure of the first step which is gradually increasing at the subsequent steps indicates that piston rings are worn-out. Small pressure of the first step which does not increase at the subsequent steps indicates leak in valves or on the punched laying of a head. Deposits on the lower parts of valves can become the reason of a low compression also.

6. If when conducting check you have doubts, address experts.

7. If pressure, in any cylinder too low, carry out the following inspection to establish the reason.

8. Pour in a teaspoon of pure engine oil in the cylinder through an opening of a spark plug and repeat check of pressure.

9. If after oil addition pressure of compression increased, then it means that the piston or the cylinder is worn-out. If pressure did not increase, so the reason in the worn-out or burned valves or in the punched laying of a head of cylinders.

10. Low pressure in two next cylinders practically always means that between them laying of a head is punched.

11. If in one of cylinders pressure is about 20% lower, than in the others, and the engine badly idles, it means that the reason, perhaps, the worn-out cam of the camshaft is. If pressure very high probably combustion chambers are covered with carbon deposits.

12. After completion of check screw in spark plugs on places and connect system of ignition.