Top Five Car Engine Problems Explained

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.