operators_manual

How to Add Coolant to the Cooling
System
Use a solution of half ethylene glycol
antifreeze and half water for best heater
performance. Do not use more than 60
percent concentration of antifreeze, as a
shortened heater life will result.
WARNING
DO NOT remove the coolant fill cap
while
the engine is hot. Scalding
steam and fluid under pressure may
escape and cause serious burns. Fail-
ure to comply may result in personal
injury or death.
NOTE
If frequent topping off is necessary and
there
are no visible signs of coolant
leaks when the engine is cold, check
for leaks with the engine operating at
normal temperature.
NOTE
DO NOT use the pressure cap to fill
the surge tank with fluid.
NOTE
DO NOT overfill a cooling system. Ex-
cess
coolant may result in overflow,
loss of antifreeze, and reduced corro-
sion protection.
1. Bulkhead Mounted Coolant Surge T
ank
1
2
3
1. Turn off the engine and let it cool
for a minimum of 10 minutes.
2. If your cooling system is built with
an air bleed valve in the upper
engine coolant pipe, open the air
bleed valve before filling the surge
tank.
3. Close any open coolant drain
valves in the lower engine coolant
pipe.
4.
Remove the surge tank fill cap (1).
DO NOT remove the surge tank
pressure cap (2).
5. Fill the system with premixed
coolant through the surge tank fill
port. Pour coolant at a steady rate
until it reaches the lower of the two
lines indicated by either "COLD
MIN" or "MIN" on the surge tank.
Wait for one minute after adding
coolant. If the coolant level drops,
add coolant until it returns to the
lower line.
6. Close the air bleed valve if opened
earlier in this procedure.
7. Start the engine and maintain an
idle at low rpm.
8. While the engine is idling air will
purge from the cooling system via
the surge tank's coolant fill port,
which will lower the coolant level in
the surge tank. Continue to fill the
surge tank until the coolant level
remains approximately 1/2 in. (13
mm) above the "MIN" line. This
may take up to 2 minutes,
MAINTENANCE - Cooling System Maintenance
Y53-6110-1A1 (01/21) 255
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