424.
Downward motion of the pistons is
4-29.
The bottom ring on the piston of
converted to rotary motion through
textbook figure 1215 serves which
the action of which of the
of the following purposes?
following components?
1.
1.
The valves
2.
The gear train
2.
3.
The flywheel and the vibration
dampener
3.
4.
The connecting rod and the
crankshaft
4.
425.
Which of the following parts is NOT
a structural component of a piston?
4-30.
The
It scrapes combustion products
from piston surfaces
It transmits oil to the
combustion rings
It wipes excess oil from the
cylinder walls
It removes impurities from the
oil
end of the connecting rod that
1.
The ring grooves
2.
The lands
3.
The bearings
4.
The skirt
426.
Aluminum pistons will expand more
than castiron pistons under the
same operating conditions.
For
this reason, they are designed with
which of the following types of
piston skirts?
1.
Split skirts
2.
Full trunk skirts only
3.
Slipper skirts only
4.
Full trunk and slipper skirts
427.
Which of the following parts
secure(s) the piston to the
connecting rod?
1.
The wrist pin
2.
The split skirts
3.
The piston rings
4.
The ring grooves.
4-28.
How do piston rings help an engine
perform its work?
1.
By sealing the cylinder
2.
By distributing and controlling
lubricating oil on the cylinder
wall
3.
By transferring heat from the
piston to the cylinder wall
4.
All of the above
attaches to the piston must be
fitted with a bearing of bronze! or
similar material when the piston
pin is a
1.
full floating pin
2.
fixed pin
3.
full floating or a fixed pin
4.
semifloating pin
431.
Which of the following parts may be
considered the backbone of the
engine?
1.
The pistons
2.
The crankshaft
3.
The connecting rods
4.
The bearings
432.
The vibration damper serves what
purpose?
1.
It balances camshaft speed with
crankshaft speed
2.
It reduces twisting strain on
the crankshaft
3.
It brakes the flywheel during
engine speed reduction
4.
It reduces flywheel vibration
36