DETROIT DIESEL 53
13.3 Fuel, Oil and Coolant Specifications
A high chloride coolant will have a detrimental effect
on the water softening capabilities of systems using
ion-exchange resins. Accumulations of calcium and
magnesium ions removed from the coolant and held
captive by the zeolite resin can be released into the
coolant by a regenerative process caused by high
chloride content solutions.
BULK INHIBITOR ADDITIVES: Commercially pack-
aged inhibitor systems are available which can be
added directly to the engine coolant or to bulk storage
tanks containing coolant solution. Both chromate and
non-chromate systems are available and care should
be taken regarding inhibitor compatability with other
coolant constituents (Figure B).
A non-chromate inhibitor system is recommended for
use in Detroit Diesel engines. The non-chromate
systems can be used with either water or ethylene
glycol antifreeze solutions and provide corrosion
Concentrations over 67% adversely affect freeze
protection, pH control and water softening Some of
protection and heat transfer rates (Figure D).
the approved non-chromate inhibitor systems offer the
additional advantage of a simple on site test to
Inhibitor depletion will occur in ethylene glycol base
determine protection level.
antifreeze through normal service. The inhibitors must
be replenished at approximately 500 hour or 20,000
mile intervals with a non-chromate inhibitor system.
Commercially available inhibitor systems (Fig. B)
may be used to re-inhibit antifreeze solutions.
When freeze protection is required, an ethylene glycol
Several brands of permanent antifreeze are available
base permanent antifreeze should be used. An
with sealer additives. The specific type of sealers vary
inhibitor system is included in this type of antifreeze
with the manufacturer. Antifreeze with sealer
and no additional inhibitors are required on initial fill
additives is not recommended for use in Detroit Diesel
if a minimum antifreeze concentration of 30% by
engines due to plugging problems throughout various
volume is used. Solutions of less than 30% concentra-
areas of the cooling system.
tion do not provide sufficient corrosion protection.