E30 series BMW 3

since 1983-1994 of release

Repair and car operation

+ 1. Maintenance instruction
+ 2. Maintenance
- 3. Engine
   + 3.1.2. Specifications
   - 3.2. Dismantle and major maintenance of the engine
      3.2.2. Specifications
      3.2.3. Major maintenance – the general instructions
      3.2.4. Compression check in engine cylinders
      3.2.5. Major maintenance – general comments
      3.2.6. Engine diagnostics by means of the vacuum gage
      3.2.7. Major maintenance – alternatives
      3.2.8. Dismantle of the power unit
      3.2.9. Removal and engine installation
      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 klapanny 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. Crankshaft dismantle
      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 shatunny 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 shatunny bearings
      3.2.30. Engine start-up 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. Good advice


3.2.13. Repair of valves


Places of wear of the valve

1. End face

2. A pro-point under crackers

3. A core (a part with the smallest wear)

4. A core (a part with the greatest wear)

5. Facet

6. Corbel

1. Check a valve condition (see subsection 3.2.12). Strongly worn-out valves replace.
2. If as a result of this check it will become clear that a valve condition satisfactory, measure diameter of the valve in several places. Appreciable distinction of diameters indicates wear of a core of the valve. At detection of appreciable distinction of diameters at least in two places the valve replace.
3. If satisfactory, them it is necessary to grind in a condition of valves to saddles. If on saddles there are only insignificant damages, or the saddle was exposed to repolishing, grinding in can be executed on melkodispersny structure. It is necessary to apply Krupnodispersny pritirochny structure only in case of detection of traces of deep development or a strong burn-out of saddles. In this case it is necessary to hand over a head of cylinders and valves on check to the skilled expert, whether it is necessary to define перезенковать saddles, or to replace loose leaves of saddles.
4. Before grinding in a head of cylinders put on an equal surface, combustion chambers up.
5. Put on a saddle facet a thin layer of pritirochny paste. Grinding in carry out, turning the adaptation on 180 ° in both parties and periodically raising the valve for uniform redistribution of an abrasive material.
6. If the rough structure is applied, grinding in comes to an end after formation of a monotonous opaque corbel on valve and saddle facets. Wipe the valve and a saddle from the remains of paste and continue grinding in on melkodispersny structure. Grinding in is considered finished at education on facets of the valve and a saddle of a uniform continuous corbel of grayish color. Further grinding in is not allowed, as because of excessive development of a saddle the subsequent its repair can become impossible.
7. After the completion of grinding in of all valves carefully wash out all details solvent.