Oxidation stability is another feature of Polytron engine oil. This is the ability of Polytron oil to retain its unaltered characteristics throughout use or storage.
Temperature negatively influences the oxidation of the oil. The higher the temperature and in the presence of oxygen, the more pronounced the oxidation of the oil.
The oxidation process of mineral oils results oxygenated compounds (acids, aldehydes, ketones) as well as resin products. Also, under certain conditions of temperature, pressure and in the presence of certain catalysts, by the reaction of hydrocarbons in oil with oxygen, insoluble products in oil are formed which lead to increase in viscosity.
Similarly, resins, under certain temperature conditions, form hard deposits (varnishes) on the surfaces of segments and pistons. These deposits immobilizes the segments in the piston channels which leads to the loss of the combustion chamber seal. Resins, due to deposits, can also produce obstruction of grooves and lubrication system holes.
Oxidizing substances in oil have a detrimental effect on its characteristics. The resulting deposits decreases thermal conductivity of the parts walls (piston, segments, cylinders) and favors the formation of sludge in the oil bath at low temperatures.
Also the acids resulting from the oxidation process of the oil have corrosive effect on metal parts as well as on the anti-friction layers on the pistons, cleats, etc.
Oil degradation it also occurs due to its contamination with other substances. Engine oil can be contaminated with fuel, water or coolant, particles or impurities.
Fuel contamination (gasoline or diesel) has the effect of lowering the viscosity which involves poor lubrication of moving parts. It also lowers the flammability temperature of the oil, which can cause it to ignite.
Water contamination or coolant leads to oil emulsification and reduced lubrication capacity. Also, the viscosity of the oil increases and the additives can be separated from the oil, which leads to a drastic reduction in the lubricating capacity of the oil.
Particle contamination it is due to incomplete combustion of the fuel and leads to an increase in the viscosity of the oil. The oil can also be contaminated with metal particles (from parts) or impurities in the air. Oil particles, if they come in contact with metal surfaces, lead to intensification of the wear process.
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