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


3.2.11. 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.
Engines M10 and Μ20
3. Rotating clowns of a yoke, establish in valves limiting gaps.
4. Check axial λώτς 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 (Μ10), or near rollers of yokes in a head, in its forward part (Μ20 and Μ40).
6. Remove a back cover of a head of cylinders.
7. Get from yokes lock rings (the 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 by the indicator total λώτς which compare with specified in subsection 3.2.2. If the gap exceeds norm, worn-out details replace.
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, it is necessary to remove them in car-care center.

10. Turn a cam-shaft until then yet will not weaken pressure of springs on the most part of yokes.
11. On those yokes on which the effort of a spring did not weaken, a special fork, or screw-drivers, wring out yoke yokes from cams of a cam-shaft and hold in such situation at cam-shaft removal. Screw-drivers insert 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 any more do not rest against cam-shaft cams carefully 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, it can be got from a forward part of a head a shock stripper. On engines without carving openings in rollers beat out rollers in blows from a back part of a head on a wooden pro-rate in 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 a directing level should be turned inside, big openings should be turned down, towards directing plugs of valves.
M40 engine


On this engine it is forbidden to overturn a head.

16. Check existence of numbering and oriyentatsionny labels on covers of basic necks of a cam-shaft.
17. Gradually and evenly unscrew bolts of basic covers and a cam-shaft. Remove covers.
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. Store details of equipment of each valve together in one bag that at assembly to establish on former places.

24. Compress a spring of the first valve by means of the adaptation and remove crackers. Carefully release a valve spring, remove a plate of a spring, a 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, the head should be cleared on termination of dismantling).