5-10.
Which of the following corrective actions
is recommended for pistons that are
excessively worn?
1.
Plating the piston
2.
Replacing the piston
1.
3.
Resizing the piston
4.
Metal spraying the piston
5-11.
Which of the following conditions may
cause low compression pressures that
might affect several or all cylinders of
an auxiliary diesel engine?
1.
A leaking cylinder valve
2.
A clogged air filter
3.
A clogged intake port
4.
A leaking after-chamber
5-12.
Which of the following factors may cause
excessive oil consumption during engine
operation?
1.
Worn oil rings
2.
Use of improper oil
3.
High lube oil temperatures
4.
Each of the above
5-13.
Which of the following symptoms may be
indicative of excessively worn piston
rings?
1.
High compression
2.
Hard starting
3.
Clear exhaust
4.
All of the above
5-14.
Carbon deposits that limit the flexing
movements of piston rings are usually
formed when an engine is operated under
which of the following conditions?
1.
Excessive operating temperatures
2.
High cooling temperatures
3.
Improper balance
4.
Improper load
5-15.
Which of the following factors may cause
a piston ring to extend into a port of a
ported cylinder?
1.
Excessive engine speeds
2.
Insufficient gap clearance
5-22.
3.
Insufficient ring pressure
4.
Excessive operating temperatures
5-16.
When a piston ring breaks because of
insufficient end gap, it will have (a)
bright spot(s) on what part(s) of the
ring?
1.
Upper side
2.
Lower side
3.
Ends
4.
Face
5-17.
When fitted to a liner, if a piston ring
lacks sufficient pressure to return to
its original shape, what is the ring
likely to do?
2.
3.
4.
Wear in place
Seize and buckle
Bind in the groove
Break under pressure
5-18.
Which of the following conditions
probably causes the greatest amount of
wear on piston rings?
1.
2.
3.
4.
Worn cylinder liners
Abnormal carbon deposits
Insufficient gap clearance
Excessive operating temperatures
5-19.
Which of the following positions is
recommended for piston ring gaps in order
to allow for cylinder wear?
1.
All gaps in line with the piston
bosses only
2.
All gaps 90° out of line with the
piston bosses
3.
All gaps staggered alternately 90°
with the piston bosses
4.
All gaps in line with the piston
bosses and alternate rings staggered
180°
5-20.
A ridge in a cylinder liner must be
removed when piston rings are replaced in
order to prevent the
1.
2.
bottom ring from cracking
top ring from slipping down
3.
top ring and the land from breaking
4.
rings from slipping too close
together
5-21.
If you want to determine the amount of
wear on a piston assembly, you should
measure only those areas that
1.
make contact
2.
are scored
3.
appear to be worn
4.
are pitted
Which of the following means are used
to lubricate piston pin bushings?
1.
Splash oil
2.
Pressure oil
3.
Mechanical oilers
4.
Oil rings
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