Doosan D20S-5 Operation & Maintenance Manual page 140

Maintenance Section Maintenance Section
Coolant Water Coolant Water
Hard water, or water with high levels of calcium and Hard water, or water with high levels of calcium and
magnesium ions, encourages the formation of magnesium ions, encourages the formation of
insoluble chemical compounds by combining with insoluble chemical compounds by combining with
cooling system additives such as silicates and cooling system additives such as silicates and
phosphates. phosphates.
The tendency of silicates and phosphates to The tendency of silicates and phosphates to
precipitate out-of-solution increases with increasing precipitate out-of-solution increases with increasing
water hardness. Hard water or water with high water hardness. Hard water or water with high
levels of calcium and magnesium ions encourages levels of calcium and magnesium ions encourages
the formation of insoluble chemicals, especially the formation of insoluble chemicals, especially
after a number of heating and cooling cycles. after a number of heating and
DOOSAN prefers the use of distilled water or DOOSAN prefers the use of distilled water or
deionized water to reduce the potential and severity deionized water to reduce the potential and severity
of chemical insolubility. of chemical i nsolubility.
Water Water Content Content
Chlorides Chlorides (Cl)
Sulfates (SO Sulfates (SO
Total hardness Total hardness
Total Total solids solids
PH PH
ppm = parts per million ppm = parts per m
Using water that meets the minimum acceptable Using water that meets the minimum acceptable
water requirement may not prevent drop-out of water requirement may not prevent drop-out of
these chemical compounds totally, but should these chemical compounds totally, but should
minimize the rate to acceptable levels. minimize the rate to acceptable levels.
cooling cycles.
Acceptable Water Acceptable Water
Limits Limits (PPM) (PPM)
(Cl) 50 maximum 50 maximum
) ) 50 50 maximum maximum
4 4
80mg/l 80mg/l
250 250 maximum maximum
6.0 to to 8.0 6.0 8.0
illion
-137- -137-
Antifreeze Antifreeze
DOOSAN recommends using automotive antifreeze DOOSAN recommends using automotive antifreeze
suitable for gasoline engines having aluminum alloy suitable for gasoline engines
parts. Antifreeze of poor quality will cause corrosion parts. Antifreeze of poo
of the cooling system, and thus always use of the cooling system, and thus always use
automotive antifreeze prepared by a reliable maker, automotive antifreeze prepared by a reliable maker,
and never use it mixed with antifreeze of different and never use it mixed with antifreeze of different
brand. brand.
DOOSAN recommends DOOSAN recomm ends that the coolant mix c
50% commercially available automotive antifreeze, 50% commercially available automotive antifreeze,
or equivalent and acceptable water to maintain and or equivalent and acceptable water to maintain and
adequate water pump cavitation temperature for adequate water pump cavitation temperature for
efficient water pump performance. efficient water pump
Premix coolant solution to provide protection to the Premix coolant solution to provide protection to the
lowest expected outside (ambient) temperature. lowest expected outside (ambient) temperature.
Pure undiluted antifreeze will freeze at -23 Pure undiluted antifreeze will freeze at -23
(-10 (-10 ). ).
° ° F F
Use a greater concentration (above 50%) of Use a greater concentration (above 50%) of
commercially available automotive antifreeze only commercially available automotive antifreeze only
as needed for anticipated outside (ambient) as needed for anticipated outside (ambient)
temperatures. Do not exceed the recommendatio temperatures. Do not exceed the
provided provided with with the the
automotive antifreezes, regarding the coolant automotive antifreezes, regarding the coolant
mixture of antifreeze to water. mixture of antifreeze to water.
Make proper antifreeze additions. Make proper antifreeze additions.
Adding pure antifreeze as a makeup solution for Adding pure antifreeze as a makeup solution for
cooling system top-up is an unacceptable practice. cooling system top-up is an unacceptable practice.
It increases the concentration of antifreeze in the It increases the concentration of antifreeze in the
cooling system which increases the concentration cooling system which increases the concentration
of dissolved solids and undissolved chemical of dissolved solids and undissolved chemical
inhibitors in the cooling system. Add antifreeze inhibitors in the cooling system. Add antifreeze
mixed with water to the same freeze protection as mixed with water to the same freeze protection as
your cooling system. your cooling system.
Use the chart below to assist in determining the Use the chart below to assist in determining the
concentration of antifreeze to use. concentration of antifreeze to use.
Antifreeze Antifreeze Concentration
P P r r ot ote e c c t t i i o o n T n Te e m m p p e e r r a a t t u u r r e e
Protect Protect ion ion to to -15 -15° ° C C (5° (5° F) F)
Prot Prot ection ection to to -23 -23° ° C C (-10° (-10°F) F)
Prot Prot ection ection to to -37 -37° ° C C (-34° (-34°F) F)
Prot ection Prot ection to to -51 -51° ° C C (-60° (-60°F) F)
NOTICE NOTICE
having aluminum alloy
r quality will cause corrosion
that the coolant mix contain ontain
performance.
recommendations,
commercially commercially available available
Concentrations s
C C o o nc nce e nt ntr r a a t t i i o o n n s s
30% 30% antifre antifre eze eze and and 70% 70% water water
40% 40% antifre antifre eze eze and and 60% 60% water water
50% 50% antifre antifre eze eze and and 50% 50% water water
60% 60% antifre antifre eze eze and and 40% 40% water water
° ° C C
ns,