Monaco SIGNATURE 2001 series, Руководство пользователя

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er has been consulted and provided positive evidence or data establishing sat-
isfactory performance in the engine.
Oil Function of Engine Oil:
If a lubricating oil is to work in an engine it must be capable to perform
various functions. Lubrication of the moving parts is the primary function.
The lubricating oil should be able to form a film between metal surfaces pre-
venting metal to metal contact and reducing friction. When you have a metal
to metal contact, friction heat is generated. Welding of the part can occur and
metal transfer will result in scuffing or seizing. The film of oil contacting the
surfaces will provide cushioning and shock dampening as well.
Cleaning is another function. The oil should perform as a cleaner in the
engine by flushing contaminates from critical components. These contami-
nates should be removed in the filtration system or during the course of an
oil change. Oil will provide a protective barrier to prevent corrosion of non-
like metals.
Internal components of the engine require cooling. The primary coolant
system cannot provide this cooling. Oil will transfer heat by contacting the
various components then transferring to the primary cooling system at the oil
cooler. The uneven surfaces are filled to react as a combustion seal within the
cylinder liner and other internal components.
Synthetic Engine Oil:
Extreme environments where ambient temperatures can be as low as
-45º C (50º F) a petroleum based oil will not perform satisfactorily in diesel
engines. Synthetic oils were developed for these type applications. These
synthetic oils are a blend from either ester and/or hydrocarbon based oils.
These base oils are produced by chemically reacting lower molecular weight
materials to manufacture lubricants of desired properties. All synthetic based
oils must meet the API category III classifications and SAE viscosity grades.
Synthetic oils and petroleum based oils should never be mixed.
Viscosity:
Viscosity is simply a measure of resistance of molecule layers moving
relative to an adjacent layer. All fluid viscosity are affected by temperature. A
multigrade lubricating oil tends to be less sensitive to temperature changes
due to formulation. Lubricating oils are generally selected for use with vis-
cosities appropriate for the expected operating temperature. The correct
selection of a lubricating oil of correct viscosity is critical for optimum per-
formance. Some effects of incorrect viscosity when the oil is too thick range
from difficulty in starting to increasing fuel consumption and reducing power
output. When the oil is too thin, oil consumption is increased as well as wear
from the metal to metal contact. This will also increase engine noise.
Low temperature viscosity specifications are identified by a “W” (winter).
Chassis Information
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