• Corrosion
• Formation of mineral deposits
• Rust
• Scale
• Foaming of the coolant
Many additives are depleted during engine operation.
These additives must be replaced periodically.
Additives must be added at the correct concentration.
Over concentration of additives can cause the
inhibitors to drop out-of-solution. The deposits can
enable the following problems to occur:
• Formation of gel compounds
• Reduction of heat transfer
• Leakage of the water pump seal
• Plugging of radiators, coolers, and small passages
Glycol
Glycol in the coolant helps to provide protection
against the following conditions:
• Boiling
• Freezing
• Cavitation of the water pump
For optimum performance, Perkins recommends a
1:1 mixture of a water/glycol solution.
Note:
Use a mixture that will provide protection
against the lowest ambient temperature.
Note:
100 percent pure glycol will freeze at a
temperature of −23 °C (−9 °F).
Most conventional antifreezes use ethylene glycol.
Propylene glycol may also be used. In a 1:1 mixture
with water, ethylene and propylene glycol provide
similar protection against freezing and boiling. Refer
to Table 12 and refer to table 13 .
Table 12
Ethylene Glycol
Concentration
Freeze Protection
50 Percent
−36 °C (−33 °F)
60 Percent
−51 °C (−60 °F)
NOTICE
Do not use propylene glycol in concentrations that ex-
ceed 50 percent glycol because of the reduced heat
transfer capability of propylene glycol. Use ethylene
glycol in conditions that require additional protection
against boiling or freezing.
Table 13
Propylene Glycol
Concentration
Freeze Protection
50 Percent
−29 °C (−20 °F)
To check the concentration of glycol in the coolant,
measure the specific gravity of the coolant.
Coolant Recommendations
• ELC
Extended Life Coolant
• SCA
Supplement Coolant Additive
• ASTM
American Society for Testing and
Materials
The following two coolants are used in Perkins
diesel engines:
Preferred
– Perkins ELC
Acceptable
– A commercial heavy-duty antifreeze
that meets ASTM D6210 specifications
NOTICE
The 400F
industrial engines must be operated
with a 1:1 mixture of water and glycol. This con-
centration allows the NOx reduction system to op-
erate correctly at high ambient temperatures.
NOTICE
Do not use a commercial coolant/antifreeze that only
meets the ASTM D3306 specification. This type of
coolant/antifreeze is made for light automotive
applications.
Perkins recommends a 1:1 mixture of water and
glycol. This mixture of water and glycol will provide
optimum heavy-duty performance as an antifreeze.
This ratio may be increased to 1:2 water to glycol if
extra freezing protection is required.
A mixture of SCA inhibitor and water is acceptable
but will not give the same level of corrosion, boiling
and, freezing protection as ELC. Perkins
recommends a 6 percent to 8 percent concentration
of SCA in those cooling systems. Distilled water or
deionized water is preferred. Water which has the
recommended properties may be used
SEBU8609
59
Refill Capacities
Fluid Recommendations