To keep engines operating at newness efficiency,
all forms of rust formation must be prev ented. The
formation of rust in the cooling system is a result of
The cooling system is pressurized.
the interaction of water, iron, and oxygen, and can
Personal injury may result when
only be prev ented by maintaining full strength
removing the radiator cap after the
corrosion protection at all times.
operating temperature is reached.
Use proper protection when removing
For rust protection during the winter months an
the radiator cap.
antifreeze hav ing a corrosion prev entiv e should be
installed in the fall. When spring arriv es, drain the
old antifreeze solution from the cooling system as
1. Coolant shut-off valves to heaters and other
all corrosion inhibitors are weakened and may be
accessories should be open to allow complete circulation
entirely exhausted by this time depending on how
during cleaning, flushing, and draining. Run the engine
the engine has been taken care of and how many
with radiator covered if necessary until temperature is up
operating hours hav e been put on it. To rustproof
to operating range 160 to 180 degrees F (71 to 82
the cooling system for summer driving, add a good
degrees C). Stop the engine, remove the radiator cap,
rust inhibitor with the first fill of clean water, if
and drain the system by opening the drain cocks on the
water is to be used, in the spring. This solution
radiator and engine block.
should then be drained in the fall and a fresh filling
of chemically treated anti-freeze installed. A good
2. Allow the engine to cool, close the drain cocks,
and pour the cleaning compound into the radiator
quick test to determine if the cooling system needs
according to the directions. Fill the system with water.
cleaning or flushing due to rust, scale, or grease is
to wipe the inside of the filler neck and header tank
3. Place a clean drain pan to catch the overflow, and
with the finger. If any sludge or excessiv e rust and
use it to maintain the level in the radiator. Do not spill
scale are present and ev idence by this test, the
the solution on the vehicle paint.
system needs a thorough cleaning.
4. Replace the radiator cap and run the engine at
moderate speed, covering the radiator if necessary, so
the system reaches a temperature of 180 degrees F
The cooling system of any v ehicle should be
(82 degrees C) or above, but does not reach the
drained and flushed out at least once a year.
boiling point. Allow the engine to run at least two
Unless the coolant has a corrosion prev entiv e in it,
hours, or according to recommendations of the
rust and scale will ev entually clog up the cooling
manufacturer of the cleaning compound, at 180
degrees F (82 degrees C) so the cleaning solution
system. Any effectiv e commercially available
may take effect. Do not drive the vehicle or allow the
flushing agent should be used at least once a year,
liquid level in the radiator to drop low enough to
and preferably twice a year, to ensure against a
buildup of rust and scale.
5. Stop the engine as often as necessary to prevent
6. With the engine stopped, feel the radiator core with
bare hands to check for cold spots, and then observe the
Remove the radiator cap when draining
temperature gauge reading. Where there is no change in
the system to ensure proper draining.
temperature for some time, drain the cleaning solution.
7. If clogging of the core is reliev ed but not fully
corrected, allow the engine to cool, pressure-flush