Fuel, Oil and Coolant Specifications
operation and additional inhibitor must be added to
the coolant at prescribed intervals to maintain original
strength levels. Always follow the supplier s recom-
mendations on inhibitor usage and handling.
NOTE: Methoxy propanol base permanent
antifreeze (such as Dowtherm 209, or equiva-
lent) must be re-inhibited only with compatible
corrosion inhibitor systems.
When freeze protection is required, a permanent
antifreeze must be used. An inhibitor system is
included in this type of antifreeze and no additional
inhibitors are required on initial fill if a minimum
antifreeze concentration of 30% by volume is used.
Solutions of less than 30% concentration do not
provide sufficient corrosion protection. Concentrations
over 67% adversely affect freeze protection and heat
Ethylene glycol base antifreeze is recommended for
u s e in Detroit Diesel engines. Methyl alcohol
antifreeze is not recommended because of its effect on
the non-metallic components of the cooling system and
because of its low boiling point. Methoxy propanol
base antifreeze may be used for freeze protection in
Detroit Diesel Series 53 engines. Before installing
methoxy propanol base antifreeze in a unit, the entire
cooling system should be drained, flushed with clean
If deposits are present, the cooling system must be
chemically cleaned with a commercial grade heavy-
The inhibitors in permanent antifreeze should be
replenished at approximately 500 hour or 20,000 mile
intervals with a non-chromate inhibitor sytem.
Commercially available inhibitor systems may be used
to re-inhibit antifreeze solutions.
Fig. 4 - Coolant Freezing and Boiling
Temperatures vs. Antifreeze Concentration (Sea
Several brands of permanent antifreeze are available
essential that these systems be kept clean and leak-
with sealer additives. The specific type of sealer varies
free, that filler caps and pressure relief mechanisms be
w i t h the manufacturer. Antifreeze with sealer
correctly installed at all times and that coolant levels
additives is not recommended for use in Detroit Diesel
be properly maintained.
engines due to possible plugging throughout various
areas of the cooling system.
WARNING: Use extreme care when removing a
radiator pressure control cap from an engine.
The sudden release of pressure from a heated
cooling system can result in a loss of coolant
and possible personal injury (scalding) from the
All Detroit Diesel engines incorporate pressurized
cooling systems which normally operate at tempera-
1. Always use a properly inhibited coolant.
tures higher than non-pressurized systems. It is