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 recommendations on inhibitor usage and handling.
NOTE: Methoxy propanol base permanent antifreeze (such as Dowtherm 209, or equivalent) 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 use 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
water and examined for rust, scale, contaminants, etc. If deposits
are present, the cooling system must be chemically cleaned with a
commercial grade heavy-duty de-scaler.
The inhibitors in permanent antifreeze should be replenished at
approximately 500 hour or 20,000 mile intervals with a non-chromate
inhibitor system. Commercially available inhibitor systems may be
used to re-inhibit antifreeze solutions.
Several brands of permanent antifreeze are available with sealer
additives. The specific type of sealer varies with the manufacturer.
Antifreeze with sealer additives is not recommended for use in
Detroit Diesel engines due to possible plugging throughout various
areas of the cooling system.
All Detroit Diesel engines incorporate pressurized cooling systems which normally operate' at temperatures higher than
non-pressurized systems. It is Fig. 4 - Coolant Freezing and Boiling Temperatures vs. Antifreeze Concentration (Sea
Level) essential that these systems be kept clean and leakfree, that filler caps and pressure relief mechanisms be
correctly installed at all times and that coolant levels be properly maintained. 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 hot liquid.
1. Always use a properly inhibited coolant.