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


3.2.15. Removal of pistons and rods



For removal of pistons and rods it is necessary to remove a head of cylinders and the pallet. On M10 and M20 engines it is also necessary to remove the oil pump (see subsection 3.1.15).


1. If in the top part of cylinders the fillet (it is checked наощупь) was formed, then it should be removed development, otherwise at removal of the piston it is possible to break rings.
2. Turn the engine the crankshaft up.
3. Check an axial side play of rods, inserting probes between a cheek of the crankshaft and a rod. The axial side play will be equal to the total thickness of probes at which the side play disappears. If the axial side play of a rod exceeds standard value, then rods should be replaced. If new rods are established (or the crankshaft), then the axial side play can be less norm (in this case it is necessary to proshlifovat rods, if necessary consult in a workshop of car service). Repeat the procedure for other rods.
4. In the absence of tags on rods and covers of rods to a nakernita on them number of the corresponding cylinder.
5. Weaken an inhaling of nuts of conrod covers, turning off them on 1/2 turns at one time until nuts do not begin to turn away by hand. Uncover a rod of the first cylinder together with an insert, do not take an insert from a cover.

6. Push out the piston with a rod and an insert through the top part of the cylinder, previously having dressed hose pieces on hairpins (if are available). If resistance to movement of the piston is felt, then 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. Do not remove the piston from a rod yet.