BMW 3 series E30

Since 1983-1994 of release

Repair and car operation

14.12. Whether it is possible to mix import oils?

THE GENERAL DATA

This and questions similar to it interest many motorists. The answer to the first – unfortunately, no even if it is oils of firms "with a world name" (Shell, Mobil, British Petroleum). Each firm makes commodity oils, adding to an oil basis the whole complex of the additives which chemical compound keeps in the big secret. Therefore, many the qualitative oils of identical appointment made under requirements concerning ekpluatatsionno-technical properties of international classification API and European specification SSMS-ASEA, but on technologies of various firms, at mixing are capable to create mixes of poor quality owing to interaction and взаимоуничтожения additives, that is "incompatibility" of additives. Oils of different firms are interchangeable, about possibility of use of such oils often specify моторостроители. But it does not mean that they can be mixed. Classification API and specification АСЕА assume obligatory identical test methods (laboratory, bench – motor etc.) oils of different firms. At desire (or necessities) моторостроители can enter additional tests (or more severe constraints) to these classifications.

The same concerns mixing of mineral or synthetic oils (sometimes – even one firm). Oils synthetic can have structure of hydrocarbonic character (in such cases of oil of one firm it is possible to mix, on what the firm the manufacturer of oil and makes recommendations for what it bears responsibility), other chemical compound. Unfortunately, cases when at mixing of oils their quality worsens are frequent. As a result of it can "begin to knock" the engine as the mix of incompatible oils turns to "jelly".

Even more negative answer to a question on possibility of mixing of import and domestic oils, especially what are made with the additive of "domestic" additives. Neither the seller, nor the consumer do not know structure of additives which are in oils. Some oils of "a domestic origin" are made by the "firms" which do not have even elementary knowledge on mineral oil. Sometimes such "experts" use the fulfilled oils (even without appropriate regeneration) to manufacture of "commodity". Thus and corresponding quality. Therefore concerning possibility of mixing of oils it is necessary to give councils very cautiously!

No "cleaners" ("Tokron", etc.) are capable to raise октановое gasoline number. For this purpose use special additives – antidetonators which add in the course of gasoline manufacturing at petrofactories, or additives. The detonation reason (metal knock in an engine operating time is audible) and калильного ignitions (the engine continues to work at the switched off ignition) can be deposits in the combustion chamber.

Compression increase in system "at introduction of some additives" occurs not for the account вязкостных additives as they do not incorporate them, and for other reasons. But it already a theme of separate conversation.

To reduce oil charcoal fumes in the old engine and to raise a compression in cylinders at the expense of use высоковязкостных oils it is inexpedient, поскольу it will lead at first to really increase of a compression in cylinders, but for a short while. Further engine repair will cost dearer.

The reason of "acoustic noise" in the old engine is its deterioration. Therefore, repair with the subsequent use of high-quality oil will more cheaply manage. It is possible to "reduce" backlashes additives, but it is necessary to understand expediency of it not to do much harm to the engine.

Now apropos "ship oils" and possibility of their use in "road diesel engines". There are different oils. Special ship oils for diesel engines concern group E, for example, М-16Е30, М-16Е60, М-20Е60, intended for малооборотных the diesel engines working on высокосерном высоковязкостном fuel – black oil. These oils have tehniko-operational properties (quality indicators), qualities of oils of "road" diesel engines different from indicators, therefore their use in automobile diesel engines it is impossible. There are ship oils of group D, for example, М-10ДЦЛ20, М-14ДЦЛ20, М-14ДЦЛ30 which are used in the diesel engines working on высокосерном fuel. Oils waterproof, but have the raised alkaline number and high зольность. For "road", that is automobile diesel engines it is the raised deterioration of the engine which can not pay off in due course free oil. Oil М-16ДР for ship diesel engines which work on дистиллятном fuel – diesel fuel with the raised viscosity compared with viscosity "automobile" and the maintenance of sulphur to 0,5 %, can be used in "road" diesel engines in the summer (for "heavy" cargo, instead of cars).

It is necessary to take for a rule: to use high-quality oil of one mark corresponding to the engine (on classification) and not to risk to mix it with same synthetic (or semisynthetic) oil. The engine will thank for it reliable work. Do not buy oil privately as packing is easy for forging.