VII.
SERVICE AND MAINTENANCE
B. FLUIDS
85
SERVICE AND MAINTENANCE
COOLING SYSTEM
COOLANT TYPE–
Your cooling system should always be suf-
ficiently charged with an adequate mixture of antifreeze and water,
regardless of the climate, in order to maintain a broad operating tem-
perature range. Your cooling system has been factory charged with
an ethylene-glycol based antifreeze.
CHECKING CONCENTRATION–
The radiator cap is located
toward the rear of the engine compartment (fig. 7.85-1). Never re-
move the cap from a hot engine. Always allow the engine to cool be-
fore servicing the cooling system.
A 50/50 antifreeze/water mixture is a conservative mixture which
allows good protection against both overheating and freezing. If a stronger antifreeze mixture is required, be
sure not to exceed the engine manufacturer’s guidelines for anti-
freeze mixing. The table in figure 7.85-2 gives a few examples of eth-
ylene-glycol antifreeze/water mixture protection values. Consult the
engine manufacturer’s handbook for further information.
Concentration should be checked every 500 hours or at the be-
ginning of each winter, whichever comes first. A refractometer should
be used to check concentration, “floating ball” type density testers
are not accurate enough for use with heavy duty diesel cooling sys-
tems.
CHANGING COOLANT–
Your coolant should periodically be
changed to eliminate the buildup of harmful chemicals. Drain and replace the coolant every other spraying
season or 1,000 hours of service, whichever comes first. Refill only with soft water because hard water con-
tains minerals which break down the anti-corrosion properties of antifreeze.
FIG 7.85-2
40%
-23ºC -10ºF
50%
-37ºC -34ºF
60%
-54ºC -65ºF
Ethylene Glycol
FIG 7.85-1
