Worksheetssmall engines 51/75
Total questions: 24
Worksheet time: 12mins
Name
Class
Date
1.
In an overhead valve configuration, where are the rocker arms installed?
a)
in the block
b)
to the crankshaft
c)
in the cylinder head
d)
in the crankcase
2.
. The rocker arms operate like:
a)
gears
b)
springs
c)
lifters
d)
levers
3.
When one end of the rocker arm is pushed up, the other end pushes down on the ____________.
a)
camshaft
b)
crankshaft
c)
valve stem
d)
valve head
4.
In an overhead cam design, the camshaft may be positioned directly over the valves or they may be offset. If the camshaft is offset, ____________ are added to the design to transfer motion from the camshaft to the
a)
pushrods
b)
lifters
c)
rocker arms
d)
springs
5.
The camshaft in an overhead cam design is usually driven by either a ________ or ________.
a)
chain or gear
b)
chain or belt
c)
belt or gear
d)
gear or shaft
6.
The overhead valve design as comapared to the L-head design can increase fuel efficiency by as much as ________.
a)
5%
b)
10%
c)
25%
d)
50%
7.
Which part of the engine must be removed before the push rods can be removed?
a)
rocker arms
b)
valves
c)
valve springs
d)
piston
8.
If the push rods are bent they must be:
a)
sanded
b)
measured with a micrometer
c)
straightened
d)
replaced
9.
Which of the following types of engines have valves and springs that are capable of being removed with your hands without the use of tools?
a)
straight valve engines
b)
2-cycle engines
c)
L-head engines
d)
OHV engines
10.
Which of the following statements is true?
a)
Most valve face angles are 60 degrees
b)
To adjust the tappet clearance on OHV engines, the valve stem must be ground.
c)
Valve guides can be replaced
d)
If valves are warped they can still be used
11.
The basic purpose of a carburetor is to:
a)
eqaulize atmospheric pressure
b)
clean the air entering the engine
c)
regulate the amount of fuel entering the engine
d)
regulate the mixture of air and fuel
12.
The ideal air to fuel ratio by weight for a small engine is:
a)
10:1
b)
15:1
c)
20:1
d)
25:1
13.
A flexible piece in the carburetor that pulsates when a vacuum is created in the engine and draws fuel into a chamber of the carburetor is called a:
a)
venturi
b)
diaphragm
c)
spring
d)
float
14.
Gum deposits which clog the carburetor and other fuel system parts are caused by:
a)
overheating
b)
stale gasoline
c)
inadequate operating speeds
d)
stalling
15.
If black smoke is coming from the exhaust when the engine is operating at 3000 rpm’s, the most probable cause is:
a)
a lean air-fuel mixture
b)
an improperly installed breather
c)
improper set ignition points
d)
a rich high speed air-fuel mixture
16.
The air-fuel mixture entering a two-stroke cycle engine initially enters the engine through the:
a)
intake valve
b)
carburetor
c)
reed valve
d)
intake port
17.
The term which does not represent a type of carburetor found on small gasoline engines is the:
a)
nozzle feed
b)
float feed
c)
suction feed
d)
diaphragm
18.
The purpose of the venturi on a carburetor is to:
a)
mix the correct amount of fuel and air
b)
increase air speed/increase pressure
c)
. decrease air speed/increase pressure
d)
increase air speed/decrease pressure
19.
According to Bernoulli’s scientific principle, as air speed __________, it’s pressure __________.
a)
increases, decreases
b)
increases, increases
c)
decreases, is reduced
d)
decreases, decreases
20.
The air-fuel mixture is forced into the intake manifold by ____________.
a)
increased pressure
b)
throttle acceleration
c)
atmospheric pressure
d)
emulsion tubes
21.
Which of the following is not a basic type of carburetor?
a)
natural draft or side draft
b)
updraft
c)
downdraft
d)
angled draft
22.
The purpose of the carburetor float is to:
a)
increase pressure
b)
keep a tight seal in the carburetor
c)
maintain a constant level of fuel in the float bowl.
d)
decrease pressure in the venturi
23.
The needle valve in the carburetor float bowl has a needle point that can be of which two types?
a)
neoprene or stainless steel
b)
neoprene or brass
c)
plastic or brass
d)
plastic or stainless steel
24.
The carburetor float can be made of which two types?
a)
neoprene or stainless steel
b)
neoprene or brass
c)
plastic or brass
d)
plastic or stainless steel
100 %
