Navistar ProStar+ Operation And Maintenance Manual page 237

1. Deaeration Tank
2. Vented Fill Cap
3. COLD MIN and COLD MAX Lines
NOTE: Vented fill cap may differ slightly in location on tank
between engine sizes.
To function properly, the coolant system must be completely filled
with coolant and all air must be expelled. To accomplish this, the
following procedures should be carefully completed:
1. Turn on ignition without starting the vehicle. This opens
the electrically actuated coolant flow valve.
2. Fully open cab heater coolant shutoff valves and coolant
system vent valve.
3. Remove fill cap and pour a 50/50 mixture (75/25
if it has been flushed with water) of the proper
coolant concentrate (refer to Lubricant and Sealer
Specifications in section Maintenance Intervals and
Specifications) and demineralized or distilled water
into the deaeration tank. A 50/50 coolant mixture will
achieve a -34°F (-37°C) freeze point. A 53/47 coolant
mixture will achieve a -40°F (-40°C) freeze point. The
first pour should reach to the top of the reservoir fill
neck.
4. Because the radiator fills slowly, it is important to
continue to top off the system for 2 minutes following
the initial fill.
5. Close coolant system vent valve, start the engine, and
continue to add enough coolant to keep the coolant level
between the COLD MIN and COLD MAX levels marked
on the deaeration tank. Replace the deaeration tank cap
tightly after adding make-up coolant for 2 minutes.
6. Run engine at governed speed until engine fan has fully
engaged for 5 minutes. Do not exceed 220°F (104°C).
7. Let engine completely cool. Recheck coolant level and
concentration / freeze point with a refractometer and top
Maintenance Instructions
225