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


3.2.15. Removal of pistons and rods



For removal of pistons and rods it is necessary to remove a head of cylinders and the pallet. On engines M10 and М20 it is necessary to remove also the oil pump (see subsection 3.1.15).


1. If in the top part of cylinders the fillet (it is checked наощупь) was formed, it should be removed development, otherwise at removal of the piston it is possible to break rings.
2. Overturn the engine the crankshaft up.
3. Check axial люфт rods, inserting щупы between a cheek of the crankshaft and a rod. Axial люфт it will be equal to total thickness щупов at which люфт disappears. If axial люфт a rod exceeds standard value, it is necessary to replace rods. If new rods (or the crankshaft) are established, люфт less norm (in this case it is necessary прошлифовать rods, if necessary consult in a car-care center workshop) can be axial. Repeat procedure for other rods.
4. In the absence of labels on rods and covers of rods накерните on them number of the corresponding cylinder.
5. Weaken an inhaling of nuts of shatunny covers, turning on them on 1/2 turns at one time, until then while nuts will not begin to turn away by hand. Uncover a rod of the first cylinder together with the loose leaf, the loose leaf from a cover do not take.

6. To Vytolknita the piston with a rod and the loose leaf through the top part of the cylinder, previously having dressed on hairpins (if are available) hose pieces. If resistance to piston moving is felt, check purity of removal of a fillet.
7. Turning the crankshaft, get rods with pistons from other cylinders.
8. Collect rods with covers and bearings, tighten nuts of covers by hand. The piston from a rod yet do not remove.