BMW 5 Series E39

since 1996-2001 release

Repair and operation of the car

+ Introduction
+ Maintenance instruction
+ Current leaving and service
- Engine
   - Procedures of repair of the engine
      Check of a compression
      Removal and installation of the lower guard of a motive compartment
      Removal and installation of the engine
      Removal and installation of the inlet pipeline
      Removal and installation of a head of cylinders
      Removal and installation of the camshaft
      Removal and installation of valves
      Check of the directing valves
      Processing of saddles of valves in a head cylinders / grinding in of valves
      Removal, installation and tension of a maple belt
   + Engine lubrication system
+ Cooling systems, 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
+ Schemes of electric equipment
+ System of onboard diagnostics

Check of a compression

The compression gives an idea of a condition of the engine, namely of degree of wear of valves and pistons (piston rings). Besides, on the basis of the data obtained as a result of check of a compression it is possible to judge need of replacement of the engine or its repair.

For conducting check it is required компрессометр.

For the diesel engine it is necessary компрессометр with a big range of measurement.

The main indicator of a compression is the difference in pressure in separate cylinders. The difference of pressure in separate cylinders has to be no more than 1.5 bars. If this value exceeds 1.5 bars, then it indicates damages of valves, wear of piston rings or the surface of the cylinder. At achievement of a limit of wear the engine is subject to repair or replacement.

At petrol engines it is necessary to turn out spark plugs. It is recommended to combine it with planned replacement of candles. At diesel engines for check of a compression glow plugs are turned out.

Value of pressure of compression is of secondary importance since it depends among other things on the applied kompressometr. For petrol engines pressure has to make not less than 10 bars, at diesel engines not less than 20 bars.

Condition of check is the charged rechargeable battery.

For check of a compression the petrol engine needs to be warmed up, the diesel engine can be cold.

Petrol engine


1. Start and warm up the engine. The index of temperature of cooling liquid has to show the corresponding temperature. Stop the engine, switch off ignition.
2. Remove a box of the filter of clean air on the right in a motive compartment, looking in the direction of the movement that it was possible to reach electronics box.

3. Unscrew screws of fastening and uncover a box of electronics (1). Address an accompanying illustration.
4. Remove the main relay (1) DME (Digital electronics of the engine) that during check there was no fuel injection. (2 - engine safety locks for DME). Address an accompanying illustration.

5. Remove all spark plugs.

Establish RKPP in neutral situation and tighten the parking brake. Several times turn a starter the engine to remove waste of products of combustion and soot from the engine.

6. Press or screw компрессометр in an opening for a spark plug according to the instruction for its operation.
7. Ask the assistant to press the accelerator pedal and to hold it during check.
8. Turn the engine approximately on eight turns so that the device did not show increase in pressure any more.
9. One after another check all cylinders and compare the received values to set.
10. After completion of check screw to the place of a spark plug, address the Section Check and replacement of spark plugs.
11. Install the main relay, close the block of safety locks.
12. Install a box of the air filter.

Diesel engine


1. Remove a box of the filter of clean air on the right in a motive compartment, looking in the direction of the movement that it was possible to reach electronics box.

2. Unscrew screws of fastening and uncover a box of electronics (1).

3. Disconnect the relay of preliminary heat, its working situation address the Section Check, removal and installation of candles of an incandescence
4. Disconnect an electric cable at candles of an incandescence and turn out candles the corresponding head.
5. Screw instead of incandescence candles компрессометр.
6. Press a starter and hold it until pressure on a kompressometra does not cease to grow. Write down value of pressure. Take off compression pressure one after another of all cylinders.
7. After check screw glow plugs again, having tightened their moment 25 Nanometers. Previously grease a carving with high-temperature CRC paste.
8. Fix by the moment 5 Nanometers cables on glow plugs.
9. Install the relay of preliminary heat.
10. Close electronics box. Install a box of the filter of clean air.