Operation and maintenance manual

Cooling System QSB4.5 and QSB6.7
Page 5-2 Section 5 - Maintenance Procedures at 500 Hours or 6 Months
Fill the cooling system with coolant to the bottom of the fill
neck in the radiator fill or recovery/expansion tank.
NOTE: Some radiators have two fill necks, both of which
must be filled when the cooling system is drained.
Maintenance Check
CAUTION
Over-concentration of antifreeze or use of high
silicate antifreeze can cause damage to the engine.
Check the antifreeze concentration. Use a mixture of 50-
percent water and 50-percent ethylene glycol or propylene
glycol-base antifreeze to protect the engine to -32°C
[-25°F] year-around.
The Fleetguard™ refractometer, Part Number C2800,
provides a reliable, easy to read, and accurate
measurement of freezing point protection and glycol
(antifreeze) concentration.
Antifreeze is essential in every climate as it broadens the
operating temperature by lowering the coolant's freezing
point and by raising its boiling point.
The corrosion inhibitors also protect the cooling system
components from corrosion and provide longer
component life.