Golden Dragon XML6125CLE, Руководство по ремонту

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General Instructions GI-6126J12-01
GI-20
b) Alcohol ether brake fluids may be adopted where there is a dry climate. The temperature
properties of the brake fluid shall be determined according to atmospheric temperature and
brake intensity;
c) Grease brake fluids shall be adopted where it is wet and rainy. The temperature properties of
the brake fluid shall be determined according to atmospheric temperature and brake
intensity.
 Automobile antifreeze fluid
Clean water can be used as cooling fluid for water-cooled engines. However, it will freeze at a
temperature below 0°C and thus cause damages to certain mechanical parts. It is necessary to add some
chemical fluid called antifreeze fluid into the refrigeration system in order to prevent failure of the
refrigeration system at a low temperature.
1) Main types and properties of automobile antifreeze fluids
a) Alcohol type:
Alcohols and water may be mixed together in different ratios to make antifreeze fluids with
different freezing points. This type of antifreeze fluid features good fluidity and it has diversified
sources at a low cost. However, the volatility of alcohols may easily cause the freezing point of
the antifreeze fluid to rise. Meanwhile, it has poor safety considering the inflammability of
alcohols.
b)
Glycerol type:
Glycerol is characterized by a high boiling point, difficulty in vaporization, flame
retardance and limited corrosiveness to metals. However, it is not efficient in reducing freezing
point and the operating cost is high.
c)
Glycol type:
Glycol has a boiling point of nearly 200˙C (197.4˙C) and is not easily volatile when mixed
with water. Mixtures of glycol and water have an apparently reduced freezing point, -68˙C at the
lowest. Glycol has a high thermal capacity, good fluidity and high chemical stability and can
substantially improve the effects of antifreeze fluids. However, glycol is poisonous and slightly
corrosive to metals and rubbers. It is still extensively used today due to its outstanding
advantages. Preservatives and colorants are also added to improve on its deficiencies.
2) Designations and key points of selection of glycol-type antifreeze fluids
a) Main designations of glycol-type antifreeze fluids include: six designations based on
freezing point of antifreeze fluid: -25, -30, -35, -40, -45 and -50; there is also one
concentrated product which has a freezing point of -37
℃
after it is mixed with 50%
distilled water;
b)
Key points for selection of glycol-type antifreeze fluids
 Select the designation of antifreeze fluid according to the lowest working temperature of
the automobile; distilled water must be added into the preparations for concentrated
products;
 Glycols are poisonous and therefore shall not be taken in;
 Glycol-type antifreeze fluids not only have a low freezing point, but also have a high
boiling point. Therefore, they can be used perennially;
In case of normal consumption of Glycol-type antifreeze fluids in the refrigeration system of an
automobile (due to water evaporation instead of leakage), it is only necessary to replenish with distilled
water. The antifreeze property won’t be changed in this case.
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