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CONSTRUCTION WORLD
APRIL
2017
56
FUEL, OIL AND LUBRICANTS
While many consider the radiator as the
critical part of a cooling system, the use
of a high-quality coolant is essential in
optimal performance and efficiency. This is
especially critical in light of the fact that 40%
of engine failures are attributable to cooling-
system problems.
Coolant comprises water, ethylene glycol,
and a chemical portion. “The coolant is an
integral part of vehicle engine maintenance.
Its water content portion cools down the
engine, while the ethylene glycol forms
the anti-freeze portion of the mixture. The
smallest, but arguably the most important
component, is the chemical make-up, which
protects the internal surfaces of the engine,”
Tinus Naude, Cummins filtration mining
manager, explains.
A vehicle’s cooling system has various
metals, with differing sensitivity to corrosion.
Aluminium, for example, is extremely
sensitive to corrosion by chemical attack.
In order to protect aluminium components
in the engine, a silica compound forms part
of the coolant formulation to specifically
protect aluminium surfaces.
Danger of chlorine
While water is a critical ingredient, ordinary
tap water cannot be used, as this could be
detrimental to the lifespan of a vehicle’s
cooling system. “Chemicals such as chlorine
are commonly added to water to make it safe
for human consumption. These chemicals
not only disrupt the chemical makeup of the
coolant, but cause rust. This has resulted
in the specific formulation of long-life pre-
diluted coolants such as ES Complete were
formulated,” Naude elaborates.
Some industrial operations even make
use of borehole water, which is often
calcium-enriched, leading to calcium
deposits forming in an engine. These
deposits form an insulation layer that
separates the water from the engine
components it should be cooling. A 3 mm
build-up of calcium creates an equivalent
heat barrier to that of 50 mm of extra steel.
This obstructs heat transfer, leading to a
dangerous temperature spike.
ES Compleat Glycerin pre-diluted coolant
is an innovative heavy-duty engine coolant
made from Glycerin, a raw material derived
from renewable energy sources such as
biodiesel by-products. Glycerin is used in
place of ethylene glycol (EG) or propylene
glycol (PG), making for a ‘green’ product for
superior engine protection.
Regular coolant testing
Naude stresses that a good vehicle cooling
system maintenance programme should
include regular coolant testing. “It is
recommended that a cooling system test
be completed every 30 000 km to check
the quality of the vehicle’s coolant, and to
determine any level of contamination. One
of the most neglected parts of an engine
system is the cooling system, and the only
way to recover from a failure is to overhaul
the engine, which is immensely costly.”
Coolants can be tested effortlessly
and accurately with either a refractometer
or with coolant-quality test strips, both
of which are supplied by Cummins.
The Fleetguard Refractometer is a fast,
easy way to determine the freeze point
protection of both Ethylene Glycol and
Propylene Glycol coolants.
Cummins-branded Restore alkaline-
based cleaning fluid is designed to clean
a vehicle’s engine and cooling system by
removing all unwanted deposits and residue
from inside the cooling system itself. In
the event of a lack of regular maintenance,
Restore highlights any leaks or problems
detected. If the cooling system has been
maintained properly, and the correct coolant
used, Restore will ensure that the cooling
system continues to operate in good
working condition for a prolonged period.
Fleetguard range
Cummins also supplies a range of
Fleetguard coolant products, which protect
engine components against corrosion, liner
pitting, cavitation, scale and deposits and
acidification. These include ES Compleat
OAT, ES Compleat, Fleetcool EX, Fleetcool,
and Fleetcool Recycled.
For example, the environment-friendly
Fleetguard ES Compleat Organic Acid
Technology (OAT) coolant formulation is
free from harmful inorganic compounds
such as nitrite, amine, phosphate, borate
and silicate. OEMs consider these
chemicals as being particularly harmful
to human health and safety and the
environment. Other inorganic compounds
such as 2-Ethylhexanoic acid is also
particularly damaging as it degrades
silicon-based seals.
Naude points out that the Fleetguard
ES Compleat OAT coolant formulation does
not contain any harmful additives that are
declarable under the Global Automotive
Declarable Substance List. “It is the most
effective and environment-friendly solution
to the increasingly challenging maintenance
demands of today’s heavy-duty diesel
cooling systems. Using this technology,
fleet owners can extend service intervals
to 6 000 hours, or even 500 000 km,”
he concludes.
SPECIALLY-FORMULATED
coolants essential
It is essential that heavy-duty
vehicles utilise specially-
formulated coolants for optimal
performance and efficiency.
While modern diesel engines
are highly efficient, they are also
stressed and need to be looked
after. Coolant therefore plays
a vital part in proactive vehicle
maintenance.