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


3.2.11. Dismantling of a head of the block of cylinders

1. Remove a head of cylinders (see subsection 3.1.13).
2. Remove an oil pipeline. Consolidations under heads of bolts of fastening of an oil pipeline are subject to replacement.
M10 and M20 engines
3. Rotating clowns of a yoke, install limit gaps in valves.
4. Check an axial side play of a cam-shaft on the indicator, having displaced a cam-shaft in both parties against the stop and having defined a difference of indications.
5. Remove from a cam-shaft a persistent plate which is or in a forward part of a head of cylinders behind a flange of a gear wheel (M10), or near rollers of yokes in a head, in its forward part (M20 and M40).
6. Remove a back cover of a head of cylinders.
7. Get lock rings from yokes (ring of wire type is shown).
8. Check a gap between rollers and yokes. For this purpose shake a yoke here and there, without allowing sliding along the roller, and determine a total side play which compare with specified in subsection 3.2.2 by the indicator. If the gap exceeds norm, then replace worn-out details.
9. On a part of engines get rubber caps (or turn out, if caps carving) from a forward part of a head of cylinders. Caps are available in a forward part of each roller of yokes.


If in rollers there are vvarenny caps, then they should be removed in car service.

10. Turn a cam-shaft until pressure of springs on the most part of yokes weakens.
11. On those yokes on which the effort of a spring did not weaken, special fork, or screw-drivers wring out yoke yokes from cams of a cam-shaft and hold in such situation at removal of a cam-shaft. Insert screw-drivers on each yoke into gaps over clowns from valves. As a rule, it is necessary to hold 3–4 yokes therefore the assistant is required.
12. After yokes do not rest against cam-shaft cams carefully any more get a cam-shaft through a forward part of a head of cylinders. If necessary turn a cam-shaft in process of its removal. Do not damage a surface of beds under basic necks of a cam-shaft.
13. Carefully get rollers of yokes. If in the roller there is a carving, then it can be got from a forward part of a head a shock stripper. On engines without carving openings in rollers beat out rollers blows from a back part of a head at the wooden pro-rate diameter a little smaller openings in a yoke.
14. Get yokes.
15. Designate each yoke and the roller that at assembly to establish on former places. At removal of rollers remember their orientation. Small lubricant openings and dredging of the directing level have to be turned inside, big openings have to be turned down, towards the directing plugs of valves.
M40 engine


On this engine the head is forbidden to be overturned.

16. Check existence of numbering and orientation tags on covers of basic necks of a cam-shaft.
17. Gradually and evenly turn off bolts of basic covers and a cam-shaft. Uncover.
18. Get a cam-shaft and a back epiploon.
19. Prepare cash desks for hydropushers and levers of pushers.
20. Get levers of hydropushers.
21. Get persistent disks.
22. Get hydropushers.
All engines
23. Prepare bags. You store details of the equipment of each valve together in one bag that at assembly to establish on former places.

24. Squeeze a spring of the first valve by means of adaptation and remove crackers. Carefully release a valve spring, remove a plate springs, spring and a basic washer.
25. Get the valve from a head of cylinders.
26. Repeat the same actions for other valves.
27. Clear a head of cylinders (if the engine understands completely, then the head should be cleared upon completion of dismantling).