TM 5-3810-300-24&P-3
Fuel, Oil and Coolant Specifications 13.3
and no additional inhibitors are required on initial fill if a
due to possible plugging problems throughout various
minimum antifreeze concentration of 30% by volume is
areas of the cooling system.
used. Solutions of less than 30% concentration do not
provide sufficient corrosion protection. Concentrations
COOLANT RECOMMENDATIONS
over 67% adversely affect freeze protection and heat
transfer rates (Fig. 4).
1. Always use a properly inhibited coolant.
Methoxy propanol base antifreeze may be used for
2. If freeze protection is required, always use a
freeze protection in Series 71 engines. Before
permanent type antifreeze.
installing methoxy propanol base antifreeze in an engine,
the entire cooling system should be drained, flushed with
3. Re-inhibit antifreeze with a non-chromate inhibitor
clean water and examined for rust, scale, contaminants,
system.
etc. If deposits are present, the cooling system must be
chemically cleaned with a commercial grade heavy-duty
4. Always follow the manufacturer's recommendations
de-scaler.
on inhibitor usage and handling.
Inhibitor depletion will occur in ethylene glycol base
5. Do not use soluble oil.
antifreeze through normal service. The inhibitors must
be replenished at approximately 500 hour or 20,000 mile
6. Chromate inhibitors should never be used with
intervals with a non-chromate inhibitor system.
permanent antifreeze.
Commercially available inhibitor systems (Fig. 2) may be
used to re-inhibit antifreeze solutions.
7. Sealer type antifreeze should not be used.
Several brands of permanent antifreeze are available
8. Maintain prescribed inhibitor strength.
with sealer additives. The specific type of sealers vary
with the manufacturer. Antifreeze with sealer. additives
9. Do not mix ethylene glycol base antifreeze with
is not recommended for use in Detroit Diesel engines
methoxy propanol base antifreeze in the cooling system.
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