BMW 3 Series E30

since 1983-1994 release

Repair and operation of the car

+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engine
+ 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
   14.2. The changed numbers
   14.3. Purchase of the old car or mysterious set of figures and letters
   14.4. Durability of the car
   14.5. About parallelism of bridges of the car and trailer
   14.6. Preparation of the car for winter
   14.7. Rule 35
   14.8. Choice of the used car
   14.9. Engine oils
   14:10. What needs to be known, changing oil
   14:11. Emergence in deposit oil
   14:12. Whether it is possible to mix import oils?
   14:13. "Eats" much, but quietly goes
   14:14. It is rather live, than is dead …
   14:15. It is not got - useful tips
   14:16. Visit to car service
   14:17. A gear belt for the gas distribution mechanism drive
   14:18. Wear of pistons
   14:19. Valves
   14:20. Bearings of engines
   14:21. Pollution of the engine
   14:22. As the conditioner works and what to do if it failed
   14:23. Conditioner: not only "pluses", but also "minuses"
   14:24. Rules of service of the conditioner
   14:25. Antifreeze you should not disturb with antifreeze …
   14:26. What should be known upon purchase of the air filter
   14:27. Engine overheat
   14:28. What should be known to the owner of the car with the injector engine
   14:29. Accumulator
   14:30. Possible malfunctions of the rechargeable battery
   14:31. What to do with the failed generator
   14:32. The belt is guilty, and we blame the generator
   14:33. Catalyst
   14:34. Rub in one - or how to save the catalyst
   14:35. Probuksovochka
   14:36. Features of operation of the brake system
   14:37. Malfunctions of the brake system
   14:38. Brake fluids
   14:39. ABS: natural choice
   14:40. Rims
   14:41. We update rims
   14:42. Scheme of marking of a car tire
   14:43. Metal corrosion
   14:44. Automake-up
   14:45. What creaks?
   14:46. Hatch
   14:47. Safety cushion: troubles or pleasures?
   14:48. We fit well?
   14:49. Anticreeping "immunodeficiency"
   14:50. Why headlights grow dull
   14:51. Galogenka
   14:52. About the correct adjustment of headlights
   14:53. Electric motor
   14:54. From change of the places "composed" nothing changes?


14:17. A gear belt for the gas distribution mechanism drive


Today gear belts found "second wind". Practically all car makers equip the cars with the elastic drive. The German designers went further away. They widely apply a double gear belt (Duplex) as reliable connection of a cam-shaft with the krivoshipno-conrod mechanism.

The gear belt has a number of advantages before a chain. It it is obvious more expensively. It is much simpler to make a belt, than a chain. By and large, it is the closed tape from maslobenzostoyky rubber reinforced by a kapron cord with teeths, pirvulkanizirovanny to it. If to compare it to a chain, then comparison will appear not in favor of the last. The belt is much lighter than a chain that, naturally, cannot but affect the mass of the engine. Besides, engine equipped with a belt, fellow much more quietly equipped with a chain. Also "elastic band" out of an engine casing is mounted that affects time of its installation or replacement. For example, at the author of these lines on replacement of a GRM belt with the subsequent its installation on tags 25–30 minutes leave. With a chain such focus will not pass.

At the correct service and control the gear belt goes long. Domestic manufacturers, we will remind, give a guarantee for a run in 60 thousand km, foreign – and that it is more. Rover managed to postpone the time of replacement of a belt to 160 thousand.

What the correct control and service of this simple adaptation consists in? At least, than each 15–30 thousand km correctness of situation and tension of a belt has to be checked. However it does not mean that it is only necessary to remove a casing and to check, whether on the place a belt. It is the best of all to examine it, having removed from the engine. Sometimes it is difficult to notice that one of teeths overstrained. If it already occurred, then be sure that he will not stretch. Therefore, having taken off a belt, make on it a mark chalk, and further tooth behind tooth "banish" it. After installation it is also necessary to check the provision of guides and a natyazhitel. All these elements have to be on one axial, otherwise the belt will work with a distortion that will not do it good.

Important factor for work of a belt – absence on its surface of oil. Whatever was maslobenzostoyky rubber of which the belt is made, nevertheless it is not that case when "oil you do not spoil porridge". Here oil just to the detriment. Therefore it is periodically necessary to pay attention to a condition of epiploons. And if you noticed an oil leak, try to eliminate somewhat quicker it. As practice shows, stay of a belt in the oil environment cuts its resource by half, and even three times.

If to ignore this control, then consequences will not keep themselves waiting long. Through 40-50 thousand km at the expense of a belt pulling the necessary tension weakens and it begins to whip. As a result of it the heavy cam-shaft rotates not synchronously, and with lag. This asinkhroniya of operation of the motor leads to a bigger weakening of a belt. As a result there are excessive loads of teeths.

The break of several teeths in a row can lead to the fact that once the cam-shaft will remain motionless while the knee will rotate. At such moments open valves meet pistons. Result – a fiasco or a bend of the valve, its broken plugs, the broken-off cam-shaft. There are, however, also exceptions when the break is painless practically. However it is possible only on those cars in which specially on this case there are pro-points in pistons. For example, our VAZs, namely cars with VAZ-2105 engines, 1300 cubic cm, and VAZ-2108, 1500 cubic concern them see.

If the car is not equipped with such engine, break of a belt costs the owner in the round sum connected with overhaul of the engine. Cost, for example, of a belt on BMW reaches of $40. repair of the engine on the same Saab will cost of $5000. For VAZ "nine" the belt can be bought for of $25. And here repair of a cursor will pull for of $400.