5. Refill the system with the solution re-
Fill Cooling System
quired for the coming season.
Before starting the engine, close all of
the drain cocks and fill the cooling sys-
C o o l i n g System Cleaners
tem with water. The use of clean, soft
water will eliminate the need for descal-
If the engine overheats and the fan belt
ing solutions to clean the cooling system.
tension and water level are satisfactory,
A hard, mineral laden water should be
it will be necessary to clean and flush
made soft by using water softener chemi-
the entire cooling system. Scale forma-
cals before it is poured into the cooling
tion should be removed by using a quali-
system. These water softeners modify
ty descaling solvent. Immediately after
the minerals in the water and greatly re-
using the solvent, neutralize a system
d u c e or eliminate the formation of scale.
with a neutralizer. It is important that
the directions printed on the container of
Start the engine and, after normal oper-
the descaling solvent be thoroughly read
ating temperature has been reached, al-
and followed.
lowing the coolant to expand to its
maximum, check the coolant level. The
After the solvent and neutralizer have
coolant level should be within 2" of the
top of the filler neck.
been used, completely drain the engine
and radiator and flush it with clean wa-
ter. Then fill the system with the prop-
Should a daily loss of coolant be ob-
er cooling solution.
served, and there are no apparent leaks,
there is a possibility of gases leaking
NOTE
past the cylinder head water seal rings
into the cooling system. The presence of
Whenever water is added to a hot
air or gases in the cooling system may be
engine, it must be done slowly to
detected by connecting a rubber tube
avoid rapid cooling which may
from the overflow pipe to a water con-
cause distortion and possible
tainer. Bubbles in the water in the
container during engine operation will
cracking of engine castings.
indicate this leakage. Another method
for observing trapped air in the cooling
system is by inserting a transparent
tube in the water outlet line.
Reverse-Flushing
After the engine and radiator have been
thoroughly cleaned, they should be re-
Flush Cooling System
verse-flushed. The water pump should
be removed and the radiator and engine
The cooling system should be flushed
each spring and fall. The flushing oper-
reverse-flushed separately to prevent
ation cleans the system of antifreeze sol-
dirt and scale deposits clog ing the radi-
ator tubes or being force through the
ution in the spring and removes the
pump. Reverse-flushing is accomplished
summer rust inhibitor in the fall, prepar-
with hot water, under air pressure, be-
ing
the
cooling
system
for
a
new
solution. The flushing operation should
ing forced through the cooling system in
a direction opposite to the normal flow of
be performed as follows:
coolant, thus loosening and forcing the
scale deposits out.
1. Drain the previous season's solution
from the unit.
Reverse-Flush the radiator as follows:
2. Refill the cooling system with soft,
1. Remove the radiator inlet and outlet
clean water. If the engine is hot, fill
hoses and replace the radiator cap.
slowly to prevent rapid cooling and dis-
tortion of the engine castings.
2. Attach a hose to the top of the radi-
ator to direct the water away from the
3. Start the engine and operate it for 15
engine.
minutes to thoroughly circulate the
water.
3. Attach a hose to the bottom of the ra-
diator and insert a flushing gun in the
4. Drain the cooling system completely.
hose.
