Cranking quiz Flashcards
When the starter motor is operating at 5000rpm, and the crankshaft is turning at 250 RPM, what is the gear ratio between the pinion and the ring gear?
15:1
20:1
1:1
25:1
20:1
To prevent overheating the starter motor, maximum cranking time should be limited to:
45 seconds
15 seconds
1 minute
30 seconds
30 seconds
The stationary magnetic field in a starter motor is created by:
current flow through the starter housing.
current flow through the armature.
current flow through the commutator.
current flow through the field coil.
current flow through the field coil.
A conductor carrying a current when placed within a stationary magnetic field will try to move:
toward the weaker side of the magnetic field.
toward the north pole.
toward the stronger side of the magnetic field.
toward the center of the magnetic field.
toward the weaker side of the magnetic field.
The electrical voltage which is built up by the turning armature windings, and acts to limit the motors maximum rotational speed is called:
counter rotational force.
counter electromotive force.
counter magnetic force.
electromotive force.
counter electromotive force.
A cranking motor which draws 450 amps at 24 volts will produce ____________ kilowatts of power.
12.6
9.4
450
10.8
10.8
The type of winding shown in the diagram below is:
compound wound.
series-parallel wound.
parallel wound.
series wound.
compound wound.
The main function of the shunt in the winding shown in question 7 is to produce a voltage which will:
increase RPM.
Increase torque.
decrease torque.
limit RPM.
limit RPM.
The clutch shown below is a:
posi-torque
inertia drive.
fluid clutch
overrunning clutch.
overrunning clutch.
The function of the magnetic switch in the diagram shown is to:
control current to the pull in and hold in windings.
isolate the ground when the ignition is off.
control current to the starter motor.
supply a ground to the ignition circuit.
control current to the pull in and hold in windings.
The part of the starter drive which ensures the drive pinion and the flywheel mesh is the:
collar and shell assembly
sprag clutch
inner race
meshing spring
meshing spring
Safety switches are wired in ___________ in the starter control circuit.
series
series parallel
parallel
compound
series
The contacts in the over crank protection switch are _______________ when the starter temperature increases to an unacceptable level.
open all the time
closed
not used under the described circumstances
opened
opened
To release the starter solenoid quickly, the current draw in the ______________ winding reverses direction to cancel out the magnetic fields and allow the return spring to disengage the starter with greater speed.
hold in
pull in
field coil
armature
pull in
The diagram shown below illustrates a cranking circuit magnetic switch with an:
isolated ground.
does not require a ground.
internal ground
shorted coil.
isolated ground.
Which of the following conditions would result in a low current draw, low free speed condition of the starter motor?
open field coil.
poor brush to commutator contact.
tight bushings.
grounded field coil.
poor brush to commutator contact.
Which of the following conditions would cause a high current draw and higher than normal starter free speed?
open armature coil
high resistance in the solenoid contact terminals.
grounded field coil
shorted field coil.
shorted field coil.
A self powered test light, lights when connected to the starter case and the insulated brush. What problem is indicated?
the grounded brush holder is OK.
the insulated brush holder is OK.
the grounded brush holder is open.
the insulated brush holder is grounded.
the insulated brush holder is grounded.
An engine has a normal starter draw of 550 amps at 22.4 volts. When tested the draw was found to be 185 amps at 19.4 volts. What should be done next?
perform a battery capacity test.
perform a voltage drop test.
replace the starter because of a short.
check battery state of charge and recharge if necessary.
check battery state of charge and recharge if necessary.
When testing a starter armature with a self powered test light, the light comes on when one lead is on a commutator bar and the other lead is on the armature shaft. What does this indicate?
The armature is normal
The armature is open
The armature is grounded
The armature is shorted
The armature is grounded
If the metal strip shown in the diagram below vibrates, the armature is:
Testing a Model T Generator Armature Using a Growler – Model T Ford Fix
shorted.
normal
grounded
open
shorted.
What is the maximum allowable voltage drop in the starter insulated and ground side COMBINED, on a 24 volt system with 2 separate battery groups?
2.0v
1.0v
1.5v
0.5v
1.0v
The diagram shown below illustrates the procedure for testing the:
solenoid contact points for resistance.
hold in winding for ground faults
pull in winding for shorts.
pull in winding for ground faults.
pull in winding for shorts.
Which of the following conditions would NOT cause solenoid chattering?
high resistance in the isolated circuit
open in the hold in winding
low battery voltage (20v)
open in the pull in winding
open in the pull in winding
A seized engine would cause:
no starter current draw
normal starter current draw
lower than normal starter current draw
higher than normal starter current draw
higher than normal starter current draw
An OCV reading of 28.2 volts on a battery group would indicate:
battery cables are corroded causing high resistance
battery has a surface charge
battery requires a load test
one or more battery cells are open
battery has a surface charge
Ampere turns would indicate a coils:
voltage
resistance
electromagnetic strength
north and south polarity
electromagnetic strength
OCV is tested with:
ammeter
carbon pile
ohm meter
volt meter
volt meter
Which of the following starter motor field coil windings, provides the greatest starting torque?
four pole, four coil series wound field
six pole, six coil series wound field
compound wound field
six pole, six coil parallel wound field
six pole, six coil series wound field
Which of the following starter motors has a built in provision to prevent excessively high free running speed?
compound wound field
six pole, six coil parallel wound field
six pole, six coil series wound field
four pole, four coil series wound field
compound wound field
Most starter motors have ___________________ brushes as poles.
the same number
twice as many
none of the supplied answers is correct
one-half as many
the same number
Solenoid dis-engagement is accomplished by spring action and:
battery current
flywheel motion
magnetic field cancellation
the build-up of a magnetic field
magnetic field cancellation
The function of a brake washer is to _____________________.
reduce wear
increase voltage
increase amperage
increase resistance
reduce wear
A condition, other than low battery, that would cause an oscillating (chattering) solenoid would be:
an open pull in winding
an open hold in winding
a dirty contact disc
a shorted pull in winding
an open hold in winding
Thrown solder inside a starter frame would indicate:
a poor soldering job
a shorted armature
excessive cranking periods
a shorted field
excessive cranking periods
Burned commutator bars on an armature would indicate:
a shorted armature coil
an open field coil
low starter resistance
an open armature coil
an open armature coil
During a no load starter test, a low speed with a high current draw would indicate:
shorted armature windings
shorted field windings
open armature windings
dirty brushes and commutators
shorted armature windings
When performing the “starter draw test”, battery voltage dropped below 8.5 volts and the amperage draw was within the acceptable range. This would indicate:
starter switch problems
starter problems
battery problems
a normal condition
battery problems
To perform a voltage drop test, the voltmeter is connected to the portion of the circuit to be tested in:
parallel while cranking
series-parallel while cranking
series while cranking
parallel with the engine off
parallel while cranking
A dirty commutator should be cleaned with:
80 grit sandpaper
a rag and varsol
150 grit emery cloth
200 grit sandpaper
200 grit sandpaper
During a no-load starter test, a low speed with a high current draw would indicate:
dirty brushes and commutator
open armature windings
a bent armature shaft
shorted field windings
a bent armature shaft
A magnetic switch is another name for a relay
True False
True
A magnetic switch allows the control of a large current with the application of a small current.
True False
True
A neutral safety switch will prevent the starter from cranking unless the clutch pedal is depressed.
True False
False
Safety switches must always be connected in series with the magnetic switch control circuit.
True False
True
An engine ECM may prevent the cranking motor from cranking
True False
True
The over crank protection switch in the following figure, prevents the starter from overheating by opening the field coil winding when hot and preventing cranking until the starter cools
True
False
True
A cranking motor solenoid switch has two sequential functions. First to connect the power to the motor, and second to shift the drive assembly into mesh with the engine ring gear.
True False
False
The hold in winding and the pull in winding are connected at the motor terminal.
True False
False
Current is flowing through the pull in winding any time that the S terminal has power to it.
True False
False
Cranking motor magnetic switches may be 3 or 4 terminals
True False
True
The cranking motor magnetic switch may have a safety switch on the control circuit ground.
True False
True
