E30 series BMW 3

since 1983-1994 of release

Repair and car operation



E30 BMW
+ 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. Good advice
   14.2. 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 the trailer
   14.6. Preparation of the car for winter
   14.7. Rule 35
   14.8. Choice of the second-hand car
   14.9. Engine oils
   14.10. That it is necessary to know, changing oil
   14.11. Emergence in deposit oil
   14.12 whether. It is possible to mix import oils?
   14.13. "Eats" much, but silently goes
   14.14. It is rather live, than it is dead …
   14.15. It is not got - good advice
   14.16. Visit to car-care center
   14.17. A gear belt for a drive of the mechanism of a gazoraspredeleniye
   14.18. Wear of pistons
   14.19. Valves
   14.20. Bearings of engines
   14.21. Engine pollution
   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. It is not necessary to stir antifreeze with antifreeze …
   14.26. That it is necessary to know upon purchase of the air filter
   14.27. Engine overheat
   14.28. That it is necessary to know to the owner of the car with the injector engine
   14.29. Accumulator
   14.30. Possible malfunctions of the storage 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 brake system
   14.37. Malfunctions of brake system
   14.38. Brake liquids
   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. "Galogenki"
   14.52. About the correct adjustment of headlights
   14.53. Electric motor
   14.54. From change of places "composed" changes nothing?



14.40. Rims

GENERAL INFORMATION

Theory

The era of steel stamped wheels, apparently, slowly leaves in the past. Steel is forced out by easy alloys. Than the steel disk is bad? Yes, in general, almost everything it is good. Cheap, reliable, rather strong. At very strong blow does not burst, and it is rumpled – means, there is a chance it to restore. If you perceive the car only as the hard worker if you are not confused by a type of steel punching if your purse is not too burdened by notes – anything the best to you and it is not necessary. Take. Well and the one who is anxious with own image, clearly, behind the price will not stand, and will take the light-alloy. The look at it, of course, is more modern, than at the steel. And a variety of types is wider. The production technology of disks from easy alloys allows designers to embody any imaginations in metal, to do wheels in any style – from a retro to futuristic. Easy alloys give the chance to trace sensitively trick of a technical fashion that you will not tell about steel – punching it and there is a punching, on it design especially will not play, possibilities are limited, and therefore – with it it is boring.

But not only to these the desire of producers to replace steel on easy alloys speaks. There are also other reasons, not less weighty. Purely technical. For example, weight reduction. Let's notice, the gross weight of the car – if the polutoratonny device means not and will lose couple of tens kgs, hardly it will be big achievement. Speech about weight reduction of nepodressorny parts, that is all that jumps, shivers and turns under a car body. Here fight follows each kg.

Accuracy of manufacturing of light-alloy wheels is much higher, than steel. So, and balancing can be carried out more precisely. Application of a light-alloy wheel improves cooling of brake knot, and not only thanks to high heat conductivity of metals entering into an alloy but also because in it is admissible to do very big openings (without losing durability and winning in weight) that promotes the best обдуву. The listed advantages quite sufficed in order that the leading firms counted on easy alloys – aluminum and magnesian. Despite of their high cost.

Is, however, in a camp of steel disks one which can argue with light-alloy on beauty, ease and "produvayemost". It is classical spitsevy a disk. Once it was very popular, it put on the most prestigious cars, on it won races... But eventually it did not sustain the competition even with the usual stamped. First, its production more labor-consuming and consequently, he is more expensive. To stamp a nave and a rim, of course, business simple and inexpensive, but here manual assembly... Secondly, it became clear that when using a spitsevy disk it is very difficult to provide optimum controllability and stability of the car on high speeds. And in the sixties the spitsevy wheel quitted the stage. However now "legkosplavshchik" do stylizations under it as the fashion on spokes remained.

As do disks

Not uniform technical characteristics, design and disk cost are defined by an alloy. Important and what way it is made. The light-alloy wheel, both aluminum, and magnesian, can be either is cast, or forged – forging still call volume hot punching.

Molding. This way is most widespread. Cast aluminum wheels went to mass production after 1964 when Americans began to establish them on sports models. Italy and Japan in 1967 started to equip with cast disks serial cars that caused chain reaction in other countries – since then aluminum molding began to force out steel punching slowly but surely. This way is very technological. It almost does not give a waste that promotes decrease in prime cost of the final product. Is, of course, and shortcomings. First, the cast disk demands reliable protection of a surface, without it it quickly loses a trade dress – aluminum becomes covered by a whitish oksidny film. Secondly, it is fragile – at strong blow breaks up. To provide sufficient mechanical durability, it is necessary to increase thickness of walls, and it reduces so desired prize in weight.

Pour also magnesium. But in very limited quantities. In spite of the fact that cast magnesian disks give solid economy of weight (about 2,5 kg on a wheel), producers of serial cars prefer not to contact them – requirements to protection of a surface are too high. Besides, such disks quickly растрескиваются. Magnesium is good not in cast option, and in the shod.

Forging. If not the high cost caused by complexity and power consumption of technology, shod disks, probably, would win long ago the market – on the majority of characteristics they do not have the equal. At strong blow the shod disk does not burst, as cast, and is rumpled. Cracks on it it is not formed, therefore the probability of depressurization of the tubeless tire is quite small. Air, of course, can leave in a bend place закраины rims, but to rumple закраину a shod disk it is necessary to manage still – forging provides exclusive durability and rigidity of a design.

Shod wheel very easy. Compare: the steel disk for the 7th BMW model weighs 9 kg, cast aluminum – 7,8 kg (for comparison one of the easiest cast designs is taken), and shod aluminum – 6,8 kg. Corrosion firmness of a shod product is much higher, than cast. The aluminum shod disk does not demand protection – if it and do, it is rather for an insurance, instead of necessarily. Magnesian shod, of course, it is necessary to protect, but not so seriously and carefully, as cast. Shod disks, especially magnesian, in the West – very expensive pleasure also are applied only on prestigious and by racing cars.

Sizes

So, you chose a material, design and the price. Now things are easy – to buy. Also it is desirable so that: а) on you did not palm off under the pretext of firm production any samopalny rubbish which should be thrown out through couple of thousands kilometers,

б) the bought disks would suit the car not only on design, but also in the sizes. These conditions are simply for executing. It is necessary to buy, first, disks in shops with good reputation. The prices in them, clearly, corresponding, but here to you to solve, on what to hope – at random or on a guarantee. Secondly, it is necessary to know a size range of the disks suitable your car, and to be able to read the markings beaten out on disks. Therefore do not consider below-mentioned information as a persuasive educational program. It is useful.

Rim tire sizes

This nomination includes two parameters – assembly diameter and width of a rim. The complete series of assembly diameters of automobile and off-road disks looks so: 10, 12, 13, 14, 15, 16, 17, 18 and 19 inches. The disk in diameter of 10 inches to you will interest only in those cases if you go by legendary Soviet invalid motorized carriage S-3D or have the small trailer for country needs. Besides, 10-inch castors are put on tiny city micropenalties (them often call microdwarfs), but this class of cars in Russia will not be presented still for a long time – they can be used only on ideally equal roads, and with it, as we know, at us a napryazhenka. Disks with assembly diameter of 12 inches too are used redno, but, of course, to a pro-thicket. than 10-inch (on "Oka", for example). The vast majority of modern cars runs on 13, 14, 15 and 16-inch disks. Recently there was a fashion on increase in assembly diameter – those cars for which 13-inch disks are native, for example, translate on 14-inch, 15 on 16 and so on. It speaks aspiration to use the tire of low series as their rideable qualities it is better, than at tires of a high profile. And the tire series is lower, the it is less in a wheel of rubber and, respectively, more metal – is natural, if external diameter of a wheel remains invariable. When using steel disks assembly diameter especially you will not increase is will lead to increase of weight of a wheel that is undesirable. Here as it is impossible by the way disks from easy alloys have – their application allows to increase assembly diameter, without making heavier a wheel as a whole. A fashion on rubber of ultralow profiles (the tire of series 40, 35 and even 30) сподвигла tuning firms on equipment of cars экстракласса disks of very big diameters – 17, 18 and 19 inches. At a look sideways on such car and tires it is not appreciable almost – a huge brilliant disk застит eyes, and the tire looks a thin black kayemochka. Looks beautifully and it is technically quite justified, but start up this fashionable animal on our roads – to the first pothole will reach, and further? Such tuning, alas, not for us. Under our conditions the kayemochka should be thicker – at least than the 60th series. Otherwise some "iron" will not save enough.

Further. Width of a rim. At the majority of cars this size does not fall outside the limits the following row: 3,5; 4,0; 4,5; 5,0; 5,5; 6,0; 6,5; 7 inches, however on tuning updatings, on SUVs and on sports models are applied also wider disks – to 13,5 inches. How to choose the necessary width of a rim? There is a golden rule: it should be for 25–30 % less than a width of a profile of the tire. As the width of a profile of the tire is usually specified in millimeters, and width of a rim – in inches, upon purchase of disks you should make simple mathematical calculation. Let's say you look for a disk under the tire 195/70R15. Width of its profile of 195 mm. In inches it will be 7,68 (it is necessary to divide 195 on 25,4). Now take away from the received size of 25 % or 30 % and approximate to the next value from given above a standard row. Receive 5,5 inches – the rim of such width is necessary for the tire 195/70R15. Use both too wide disks, and too narrow is undesirable: the design profile of the tire (боковины or are compressed закраинами rims, or are stretched on it) is broken and, therefore, its rideable characteristics – reaction to turn, resistance to withdrawal, lateral rigidity worsen. The tolerance of width of a rim from regular size makes 0,5–1,0–1,5 inches for disks with a diameter more than 15 inches. But it is better to take, of course, a disk precisely under the tire.

Wheel departure. This distance between the longitudinal plane of symmetry of a rim and the fixing plane of a wheel. For each model of the car the departure pays off so that optimum stability and controllability of the car, and also the smallest load of bearings of naves were provided. The majority of serial cars is issued with departures of wheels on 0 mm (GAZ-3102) to +38 mm (Opel Corsa, Toyota Corolla, Mitsubishi Colt, VAZ-2109), but the range, of course, is not settled by it – models meet a departure both-46, and +59. To put on the car disks with supernumerary for this model a departure producers do not recommend. Its reduction does a track of wheels wider – though it a little and increases stability of the car, gives it more racing look, but at the same time sharply reduces a resource of bearings of naves and creates additional load of a suspension bracket (to increase a departure that is to narrow a track of wheels, it is impossible more often – the disk will rest against a support or in a brake drum).

Wheel car sizes

With it usually problems do not arise – each car owner perfectly knows, what bolts, nuts, hairpins the wheel to its car fastens. In number of fastening openings too it is difficult to be mistaken – hardly you buy a disk with four openings if on a nave of an axis of the car 5 hairpins stick out. Happens, make the wrong choice diameter of the central opening of a disk (if a mistake in a minus, the wheel simply does not sit down on a place) and diameter of an arrangement of openings of fastening. Both that, and another is specified in catalogs which are in any decent shop – before purchase of disks ask the seller to be verified with them. At native wheels of the car the central opening of a disk is, as a rule, precisely adjusted to an axis nave: at plants it is accepted to align a wheel on it – its diameter is landing. But if you buy disks in the secondary market, be not surprised to that the central opening can appear more put. Producers of spare parts often do it obviously increased diameter (a wheel in this case align on diameter of an arrangement of openings of fastening – it is designated by PCD – Pitch Circle Diameter) and supply a disk with a set transitional Kolya that allows to use it on different models of cars. But it is better to do without rings. Though in them the big crime is not present, after all than it is less in knot of "superfluous" details, subjects it is more reliable.

Marking

Marking which should be cast or beaten out in a visible place gives full information full or nearly on a disk. That is on any surface of a disk, except that part of a rim which is turned to the tire. To put marking on a landing surface it is not meaningful, as disks often are on sale assembled with tires which close inscriptions. In our market you can face different options of marking – as a rule, with Russian, American and European. They differ from each other manner of performance a little, but it should not confuse you – simply same information reaches the buyer by means of different, depending on concrete national standards, symbols. Let's consider as an example marking of the SUV of a disk of the American firm ALCOA.

The first. It, of course, a company name, its emblem (something reminding hourglasses), a sign protecting the right of the producer to be called by itself (a letter R in a circle), and the country of manufacturing of a disk (Made in USA).

Further. A standard size – 15х10JJ. It means that this disk has assembly diameter of 15 inches and width of a rim of 10 inches. Consider that on the European and Russian disks these parameters are specified in return sequence – 10JJх15, and in a tail of this inscription also any letters (for example so are attached: 10JJх15CH). In an index, the put-down ambassador of value of width of a rim (in our case it is JJ), information on design features onboard закраин this rim – every possible tilt angles, radiuses of a curve and other is coded. Instead of JJ J can be written, to JK, by K or L – depending on what form закраин rims is chosen by designers for this disk. Well and what mean the letters which have been put down after assembly diameter? Before answering this question, it is necessary to remember, in what the main difference of a disk for the chamber tire from a disk of the tubeless consists. Remembered? Available at "tubeless" хампов – special ring ledges on the regiments of a rim holding the tire from a soskakivaniye from a disk at lateral blow and at loss of pressure. Designs хампов very much – there is an idle time хамп (H is designated – Hump), is flat хамп (FH – Flat Hump), asymmetric хамп (AH – Asymmetric Hump) and still a great number of others. Sometimes on rims do the special shelf (SL – Special Ledge) which parameters are verified so that the tire reliably keeps and without хампа. Happens, on outer side of a rim хамп one type, and on internal – another. All these combinations also make a reservation in a dimensional inscription. In the European option of marking – 10JJх15CH – letters mean that on this disk the Combi Hump system (combined хамп) is applied. To penetrate into that with what is combined, to the buyer it is not obligatory, it is information for experts. Remember values of these small letters you can as required to flash only erudition in conversation with colleagues on a wheel.

On a disk manufacturing date (year and week) is surely specified. Number 0294 means that the wheel is let out in the second week 1994.

The inscription of PART NO 150410-A is number of that party of otlivka from which preparation for a disk is taken. If in use at a disk factory defect is found, trading inspection can determine by this number, in what link of a technological chain marriage is allowed. The Russian and European producers usually designate number of casting by four-unit number.

N48 T-DOT – a supervisory authority brand (saying our way, Quality Department), confirming that the goods is checked in all respects and suitable for the use. DOT means that the disk corresponds to the American standards of safety. Some firms brand the production not dry indexes, and birdies, florets and an other art.

Cast disks for beskamery tires besides a brand of usual Quality Department it is branded also рентгеноконтроля which testifies that the disk has no internal defects – lityevy sinks.

MAX LOAD of 3000 LB – maximum static weight load on a disk. Having transferred 3000 pounds to measuring system habitual to us, we will receive 1362 kg.

FORGED in a translation from English means the shod. Existence of such inscription in marking is not obligatory, it is not provided by any standards. As a rule, it do on the superfashionable disks forged from an easy alloy. It means that the manufacturing firm simply wishes потрафить to the vain buyer and to involve monetary clientele. After all shod, and especially shod magnesian disk – madly expensive (in the West) and prestigious – a sign of a solvency of the owner. And without FORGED inscription here not to manage in any way. Say, let all see, what I abrupt...

There is in the American marking one more interesting inscription: MAX PSI of 50 COLD. It means that pressure in the tire which is put on this disk, should not exceed, in our example, 50 pounds on square inch (3,5 kgfs/cm of quarter); the word cold (cold) reminds what to measure pressure in the tire follows, when it cold, that is to a trip or not right after it.

It would seem, why to specify on disk pressure of air if it is stipulated in requirements to the tire and is defined first of all it, instead of a disk, a design? Experts explained that it is a clever insurance move. Let's say at drift at great speed the car flies sideways in a border – the tire comes off a rim, the disk bursts (if it cast, shod is rumpled). Cause of accident you. naturally, consider quality of a disk (rotten palmed off, the tire does not hold) and appeal to court with intention вчинить the claim to his producer. But the court will solve business in your advantage only in case you accurately observed ALL instructions and the restrictions concerning a subject of dispute. And if it will be found out that in the tire which has been put on a disk with an inscription of MAX PSI 50, these PSI was though for pound more (it will find out, having measured pressure in the escaped tires, – it is meant that it identical on all four wheels) – compensation not to see.

For the come-off tire will not pay. It is logical: the rim reliably holds the tire, only when that is not pumped over, and a rating limit see in disk marking (in this sense, by the way, MAX PSI inscription on a disk is quite justified technically). And that is interesting, for the burst disk too will not pay. Why? Yes all therefore. Non-compliance with the instruction. It seems, what communication? And it is unimportant. Ministry of Health warned...

As we see, the inscription – is good a catch in judicial dispute. Not to pay superfluous in claims. Americans knew inside out insurance affairs. Europe did not reach yet similar pettifogging – in any case, on disks there nobody specifies tire MAX PSI. Or nearly anybody.

You, probably, paid attention that in marking of a considered disk there are no such important things, as a departure and the connecting wheel car sizes. Generally the departure is without fail specified by all European firms and the majority American (our example in this sense is atypical). Germans designate ET departure (it is admissible, ET 30, if its size positive, or ET-30 if negative), Frenchmen – DEPORT, all the others manage English OFFSET. The wheel car sizes are specified quite seldom. If you can see an inscription on any disk, for example, PCD 100/4, know that diameter of an arrangement of openings of fastening of this disk to a nave of an axis is equal 100 mm, and openings 4. The last, however, is visible and without helps.