BMW 3 Series E30

since 1983-1994 release

Repair and operation of the car

+ 1. Maintenance instruction
+ 2. Maintenance
- 3. Engine
   + 3.1.2. Specifications
   - 3.2. Dismantle and capital repairs of the engine
      3.2.2. Specifications
      3.2.3. Capital repairs – the general instructions
      3.2.4. Check of a compression in engine cylinders
      3.2.5. Capital repairs – general comments
      3.2.6. Diagnostics of the engine by means of the vacuum gage
      3.2.7. Capital repairs – alternatives
      3.2.8. Dismantle of the power unit
      3.2.9. Removal and installation of the engine
      3.2.10. Order of dismantling of the engine
      3.2.11. Dismantling of a head of the block of cylinders
      3.2.12. Cleaning and check of a head of cylinders and details of the valvate mechanism
      3.2.13. Repair of valves
      3.2.14. Assembly of a head of the block of cylinders
      3.2.15. Removal of pistons and rods
      3.2.16. Dismantle of the crankshaft
      3.2.17. Intermediate shaft (only M20 engine)
      3.2.18. Cleaning of the block of cylinders
      3.2.19. Check of a condition of the block of cylinders
      3.2.20. Honningovaniye of cylinders
      3.2.21. Check of a condition of pistons and rods
      3.2.22. Check of a condition of the crankshaft
      3.2.23. Check of radical and conrod bearings
      3.2.24. Engine assembly order
      3.2.25. Installation of piston rings
      3.2.26. Installation of an intermediate shaft
      3.2.27. Installation of the crankshaft and check of gaps in radical bearings
      3.2.28. Installation of a back epiploon
      3.2.29. Installation of rods and pistons, check of gaps in conrod bearings
      3.2.30. Launch of the engine after repair and a running in
   + 3.3. Engine electric equipment
+ 4. Cooling system
+ 5. Heating and ventilation
+ 6. Fuel system
+ 7. Exhaust system
+ 8. Transmissions
+ 9. Coupling
+ 10. Brake system
+ 11. Running gear
+ 12. Body
+ 13. Electric equipment
+ 14. Useful tips


3.2.19. Check of a condition of the block of cylinders


Telescopic нутрометр for measurement of internal diameter

1. Check existence on the block of cylinders of cracks and traces of corrosion. Check a condition of carvings in openings, note places with the stripped thread. If there were suspicions on leak of cooling liquid in the block of cylinders, then the block should be tested for tightness for what it is expedient to address to car service. At detection of defects repair the block (if it is possible), or replace.
2. Check existence of chips and zadir on the internal surfaces of cylinders.
3. Measure the internal diameter of the cylinder directly under area of a fillet parallel to and perpendicular to an engine axis. Repeat measurements on the middle and in the lower part of the cylinder. By results of these measurements define conicity and ovality of the cylinder and compare to standard.
4. In the absence of a nutromer the gap can be checked the special probes inserted in the place of the greatest friction of the piston about the cylinder (i.e. between the piston and the cylinder in one of 2 places on the axis making a corner of 90 °C an axis of a piston finger).
5. The gap is determined by thickness of the probe at which the piston moves in the cylinder under moderate effort. If the piston fails or slides, then the gap is higher norms and the piston it is necessary to replace, and to proshlifovat the cylinder. If the piston jams at position of the probe about NMT and slides at position of the probe about VMT, then conicity of the cylinder exceeds norm. If at turn of the piston in the cylinder with the laid probe the piston jams, then ovality of the cylinder exceeds norm.
6. Repeat measurements for other cylinders.
7. If gaps, conicity and ovality exceed norm, then cylinders should be chiseled under the repair size and to replace pistons and rings repair.
8. If the condition of cylinders accepted wear of the cylinder, conicity and ovality do not exceed the established norms, then cylinders it is required to otkhonningovat and replace piston rings only.