OPERATOR'S MANUAL

Cooling System Preventive Maintenance
– 148 –
PB1318 3/01 Model 330
Adding Coolant
A mixture of water and low silicate antifreeze should be used
for coolant. Water must be clean and free of corrosive and
scale-forming chemicals. Drinking water may not be good for
your vehicle. New vehicles come premixed with antifreeze
and corrosion inhibitor. Be sure different types of coolant are
not mixed. Stay with the same coolant until a complete
replacement is performed.
NOTE: Excess coolant may result in overflow, loss of
antifreeze, and reduced corrosion protection. For a
cold engine, the proper coolant level is 1 in. below
the radiator cap seal. For normal operating tempera-
tures, coolant should be even with the radiator cap
seal.
Coolant Conditioner
A variety of test methods are available for measuring coolant
conditioner levels. Test strips provide convenient and consis-
tent results with minimal training. Other test methods can be
used when appropriate training is provided. The actual test
(i.e. test strips, etc.) and coolant conditioner maintenance
schedule should be done in accordance with the actual cool-
ant conditioner manufacturer recommendations.
The coolant conditioner should be recharged according to
Table 2, “Recommended Maintenance Intervals,” Page 121,
unless otherwise specified in the Engine Manufacturer’s
Maintenance Manual. See the Medium Duty Maintenance
Manual for more information.
Antifreeze Mixture
The maximum efficient Low Silicate Ethylene Glycol anti-
freeze concentration for extended low temperature operation
is 68% glycol by volume. Exceeding this 68% limit reduces
freeze protection. Table 8, (”Antifreeze Protection — Ethyl-
ene Glycol”) shows the temperature protection provided by
low silicate ethylene glycol antifreeze in relation to the pro-
portion mixed with water. Note that 100% antifreeze is no
more effective than a 30% mixture.
Refer to Table 8, (”Antifreeze Protection — Ethylene Glycol”)
for specific antifreeze freeze point protection. To avoid possi-
ble overheating in hot weather, do not use Low Silicate Anti-
freeze concentrations greater than 50% glycol by volume
unless freeze protection below –34°F (–36°C) is also
required.