Top Five Car Engine Problems Explained

30 September 2010

PROBLEM No. 1. CORROSIVE WEAR OF THE ENGINE PARTS

Question: How does corrosion in the engine appear?

Reference of MITASU OIL expert: Corrosion appears as a result of the action of organic and mineral acids in the motor oil operation mode.

Question: How do organic acids form in oil and what effect do they have on the engine parts?

Reference of MITASU OIL expert: Occurrence of the organic acid oil is caused by oxidation of oil hydrocarbons, which continuously occur when the motor operates in the process of the air oxygen effect. The corrosive effect of organic acids on metals is especially evident in the presence of oxygen and water.

Organic acids, which almost do not impact on steel and cast iron, have a destructive effect on non-ferrous metals and especially, on lead being a part of leaded bronze, from which base and crankpin bearings of the crank shaft are often made. The availability of organic acids in oil is a peculiar integrated value of oil corrosive aggressiveness and its potential tendency for lacquer film formation and carbon buildup on the parts of the diesel sleeve group.

Question: How do mineral acids form in oil and what effect do they have on the engine parts?

Reference of MITASU OIL expert: The presence of mineral acids in oil increases its corrosive activity, mainly, in relation to cast iron and steel, as a result of which a heavy wear of the cylinder bushings, first of all, occurs. The mineral acids, namely, sulphuric acid, enter the oil film on the cylinder bushing mirror at condensation of the end product of poor fuel combustion.

Question: How does poor fuel influence on the engine parts' corrosion?

Reference of MITASU OIL expert: Poor fuel is characterized mainly with the increased sulphur content. The higher the content of sulphur in fuel, the more difficult the oxidizing process is.

Question: How one can decrease corrosion on the motor parts?

Reference of MITASU OIL expert: To prevent from occurrence of corrosive wear of the engine parts the high-quality motor oil should contain an optimal balanced set of neutralizing additive agents. At this account a constant excess of oil alkalinity is achieved and this promotes neutralization of acids formed in the film and prevents the wearing surfaces of the parts from corrosive destruction. In all oils produced by MITASU OIL CORPORATION, Japan, a set of high-technology neutralizing additive agents produced by the leading world manufacturers is used, by virtue of which a stable anti-corrosive effect is achieved.



Top Five Car Engine Problems Explained

30 September 2010

PROBLEM No. 2. DEPOSITS (CONTAMINATIONS) OF THE ENGINE PARTS

Question: What are these deposits? 

Reference of MITASU OIL expert: They distinguish two main types of deposits on the motor parts: high-temperature and low-temperature. Carbon deposits and lacquers refer to the first type, slurry - to the second one. 

Question: What is carbon deposit and what hazard does it constitute for the engine? 

Reference of MITASU OIL expert: Carbon deposit is formed in high-temperature zones, on the surface of the combustion chamber, in grooves of the piston rings and on the rings themselves. It has poor thermal conductivity, which causes overheat and heat-stressed parts. Coking of drainage outlets in the ring grooves of the oil scraper rings increases oil entering to the cylinder, which accelerates the carbon deposit formation leading to complete coking (jamming) of the piston rings and acute degradation of the engine's power and economic values. 

Question: What is the cause of the carbon deposit increase? 

Reference of MITASU OIL expert: The carbon deposit formation has a particular influence on fuel quality. The increased sulphur content in fuel has an impact on the accumulation rate and carbon deposit hardness. Russian fuels contain a big percent of aromatic and polycyclic compounds. As a result of these fuels' combustion a big quantity of incomplete combustion end products are formed; they are one of the important factors of the carbon deposit formation. Their quantity in the diesel exhaust gases in other similar conditions depends on the ratio of air excess. 

Question: What is slurry? What negative impact has it on the engine parts? How one can decrease its quantity? 

Reference of MITASU OIL expert: Low-temperature deposits (or slurry) contaminate the engine with sticky buttery masses. Slurry accumulation in the oil receiver area can break seriously the oil circulation and cause the engine damage. These are the most dangerous deposits, which can cause sudden complete or partial clogging of oil channels. 

Slurry is especially intensively formed in worn engines with a large gas leakage into the carter accelerating oxidizing processes in oil because it is established that nitrogen oxides contained in exhaust gases have a significant impact on formation of low-temperature deposits. 

Condensation of water and fuel steams typical for low-temperature operating conditions especially promotes the formation and deposit of slurry. 

Slurry is deposited on the cylinder covers, valves, in different pockets and cavities of the carter and oil trough, filters and filtering elements. The slurry sludge analysis shows that this is a water emulsion in oil, because water amounts up to 35 % of these products mass. In addition, heavy fractions, soot, asphaltenes, polycarbons, carboides, nonflammable products (ash), sulphur compounds and a number of other products accumulate in this buttery mass. 

Question: How one can help the motor and decrease deposits on its parts? 

Reference of MITASU OIL expert: The detergency of oils has a paramount importance for modern engines of any type. MITASU experience lets increasing, at the account of adding special high-technology detergent agents to oil even with poor quality of fuel, the ability of oils to solute (wash out) different deposits providing a high cleanness of the engine parts during the motor oil lifetime. 



Top Five Car Engine Problems Explained

30 September 2010

PROBLEM No. 3. MOTOR OIL CONTAMINATION

Question: How does motor oil contaminate? 

Reference of MITASU OIL expert: One of the main factors deteriorating oil in the process of its operation in the motor is its contamination. The contamination process occurs in the following directions:

– complex processes of chemical transformations of oil hydrocarbons (oxidative polymerization, etc.);

– contamination with fuel combustion end products;

– contamination with end products of additive agents activation;

– contamination with ends products of the engine wear and products entered to oil from the external environment. 

Impurities accumulated in the motor oil are of organic and inorganic origin. The following refers to organic contaminants: products of, incomplete fuel combustion; sooty and coking particles; end products of oil decomposition, oxidation and polymerization; asphaltenes; tars; oxyacids; polycarbons and carboids. Impurities of inorganic origin are represented in oil by end products of wear and corrosion; external contaminations; products of metal-containing additive agents' decomposition; different salts; cinder particles, water, etc. 

Question: What danger does oil constitute for the car motor? 

Reference of MITASU OIL expert: First of all, the motor oil leads to abrasive wear of the combustion engine (CE) parts, which occurs as a result of entering solid particles into the layer of liquid grease separating the friction surfaces, by which the contact of these particles with wearing surfaces is provided. The abrasive wear rate depends on the sizes of these particles, their commensurability with the gaps between the separate parts, as well as the form, hardness and mechanical strength of the contamination particles. Any mechanical impurities, which sizes exceed the borderline oil film thickness cause the discontinuity of the oil film and provide for contact with metal surfaces causing the increased wear of the combustion engine parts. 

Question: What is the main reason of oil contamination? 

Reference of MITASU OIL expert: It is generally acknowledged that 75–90% of contaminations are of organic origin, i.e. end products of incomplete fuel combustion. The primary sooty particles entering oil from the combustion chamber are 0.3 – 0.5 μm. In oil, theses particles form a disperse phase with a large reserve of free surface energy, which provides the particles' striving to aggregation (coarsening). The formed aggregates of sooty particles, coming to the area of high temperatures, strengthen considerably becoming abrasion-dangerous. At the same time the medium size of insoluble contamination particles, the engine parts' wear accelerates and deposits on the secondary oil filters grow. 

Question: Is it possible to solve the problem of oil contamination? 

Reference of MITASU OIL expert: Addition of dispersing-stabilizing additive agent to oil lets preventing from the process of contamination insoluble products aggregation and stabilize them in the low-dispersing state preventing from the engine part wear and blocking of the oil filters' pores.

The use of high-technology set of dispersing-stabilizing additive agents is a pledge of MITASU OIL CORPORATION motor oils quality.  

PROBLEM No 4. MOTOR OIL VISCOSITY 

Question: Is viscosity really one of the most important characteristics of the motor oil? 

Reference of MITASU OIL expert: The ability to provide liquid friction, hydrodynamic friction in bearings and, hence, their normal operation depends on oil viscosity. The oil viscosity has an impact on the wear of the crank shaft necks and bearing inserts, parts of the cylinder-piston group. In case of the optimal oil viscosity the reliable gap seal in the cylinder-piston group is provided.  

Question: How do all-season motor oils operate and how do they provide the constant set viscosity at any temperature? 

Reference of MITASU OIL expert: The viscosity decrease in operation in case of thickened (all-season) oils occurs as a result of mechanical, thermal or thermal-oxidative destruction of viscous polymer additive agents.

Question: What danger does the motor oil viscosity decrease constitute? 

Reference of MITASU OIL expert: The following are the results of operation with low-viscosity oil: melting of bearings, scuffing of the parts of the cylinder-piston group, breakdowns of the crank shaft. The high quality of thickening additive agents used by MITASU OIL CORPORATION, Japan, is a guarantee of your engine protection from the oil viscosity decrease during its operating life.



Top Five Car Engine Problems Explained

30 September 2010

PROBLEM No 4. MOTOR OIL VISCOSITY

Question: Is viscosity really one of the most important characteristics of the motor oil? 

Reference of MITASU OIL expert: The ability to provide liquid friction, hydrodynamic friction in bearings and, hence, their normal operation depends on oil viscosity. The oil viscosity has an impact on the wear of the crank shaft necks and bearing inserts, parts of the cylinder-piston group. In case of the optimal oil viscosity the reliable gap seal in the cylinder-piston group is provided.  

Question: How do all-season motor oils operate and how do they provide the constant set viscosity at any temperature? 

Reference of MITASU OIL expert: The viscosity decrease in operation in case of thickened (all-season) oils occurs as a result of mechanical, thermal or thermal-oxidative destruction of viscous polymer additive agents.

Question: What danger does the motor oil viscosity decrease constitute? 

Reference of MITASU OIL expert: The following are the results of operation with low-viscosity oil: melting of bearings, scuffing of the parts of the cylinder-piston group, breakdowns of the crank shaft. The high quality of thickening additive agents used by MITASU OIL CORPORATION, Japan, is a guarantee of your engine protection from the oil viscosity decrease during its operating life.   



Top Five Car Engine Problems Explained

30 September 2010

PROBLEM No. 5. THERMAL-OXIDATIVE STABILITY OF THE MOTOR OIL

Question: What is the thermal-oxidative stability of the motor oil? 

Reference of MITASU OIL expert: The motor oil ability to resist to oxidation at the engine operation is called thermal-oxidative stability. The main reason of oxidation is high temperatures in the engine. 

Question: What temperatures are concerned? 

Reference of MITASU OIL expert: The temperature, at which the motor oil operates in specific areas achieves and exceeds 200 °С. At such a high temperature the processes of any hydrocarbon oxidation are very active. In the areas of the piston rings, valve guides, on the surface of the pistons and cylinders, in the gaps of the bearings the oil is in the form of thin films on hot metal surfaces.  All this creates exclusively favorable conditions for its oxidation and oxidative polymerization. 

Question: What impact has this oxidative film on the engine parts on the engine operation? 

Reference of MITASU OIL expert: Indeed, one of the forms of demonstration of the thermal-oxidative processes in oil is formation of thin lacquers on the parts with the high temperature. The lacquer film thickness can be from the micron fractions to 100–200 μm. The lacquer formation deteriorates the thermal conductivity of the parts and causes their overheat and as a result, scuffing of the cylinder and jamming of the piston rings and sometimes of the piston itself.  The lacquer film is held tight on the parts and does not solute in the strongest solvents. 

Question: How one can decrease the value of the oxidative lacquer film? 

Reference of MITASU OIL expert: In practice, the sole way of action on the thermal-oxidative stability is the correct choice of basic oils including the minimum quantity of easily boiling fractions and having, maybe, a narrower fractional composition. Such oils include high-quality oil used in products of MITASU OIL CORPORATION, Japan. Their evaporability and oxidizability are less severalfold than of their analogues. This creates the favorable conditions for MITASU OIL motor oil operation in high-temperature areas of the combustion engine.