Question 4-18 is to be judged True or
False.
4-18.
The two basic types of heat exchangers
used on engines are radiator and tubular.
4-19.
In the Harrison-type heat exchanger, how
do the liquid coolants pass through the
unit?
4-20.
1.
Freshwater passes through the tubes,
and seawater passes around the tubes
2.
Freshwater passes through the tubes,
and freshwater passes through the
tubes
3.
Seawater passes through the tubes,
and freshwater passes around the
tubes
4.
Seawater passes through the tubes,
and the seawater passes around tubes
How is excessive scale on the cooler of a
heat exchanger usually indicated?
1.
By a slow increase in freshwater
temperature
2.
By a similiarity between inlet and
outlet pressures
3.
By the decrease in freshwater
temperature
4.
By a rise in the freshwater tank
level
4-21.
The temperature in the saltwater cooling
system of an engine should never be
allowed to exceed what maximum
temperature?
1.
130°F
2.
140°F
3.
170°F
4.
180°F
4-22.
Which of the following conditions can
cause a cooler element to become clogged
with foreign matter?
1.
Leak in oil cooler
2.
Dirty freshwater
3.
Faulty seawater strainers
4.
All of the above
Questions 4-23 is to be judged True or
False.
4-24.
Erosion holes in the cooler element of a
heat exchanger are usually caused by
which of the following conditions?
1.
A clogged cooler element
2.
A low-pressure water flow
3.
Air entrapped in the cooler casing
4.
Fast movement of grit particles
4-25.
By which of the following actions will
you cause internal leaks of a heat
exchanger element installed in the
engine cooling system?
1.
By increasing the oil temperature of
the cooler
2.
By reducing the water pressure to the
cooler
3.
By allowing continued cooler
operation at excessive pressure
4.
By allowing continued cooler
operation at reduced pressure
4-26.
The heat exchanger outlet side is used to
admit the proper amount of steam required
to blow through a clogged cooler element
containing which of the following
deposits?
1.
Oil
2.
Sand
3.
Grease
4.
Roth 2 and 3 above
4-27.
YOU are performing an air test on a heat
exchanger to check for leaks.
What
should you do after attaching a pressure
gage to the inlet line of the element?
1.
Immerse the element in a tank of
water
2.
Block off the discharge side of the
element
3.
Admit low-pressure air to the inlet
side of the element
4.
Remove the element from the casing
4-28.
Which of the following methods should you
use to make an emergency repair to a
strut-type heat exchanger?
1.
Plug the tube
2.
Replace the element
3.
Soft solder the element
4.
Silver solder the element
4-23.
Overlubrication of the circulating water
pump bearings will NOT affect the cooling
capacity to the heat exchanger element.
24