Provincial Prep

On an air brake system, the maximum allowable build up time for a single unit (tractor only) between 50 and 90 PSI is:

30 seconds

1 minute

3 minutes

5 minutes

Correct! Wrong!

The main function of a highway valve is to allow:

A truck application only

An emergency brake application only

A faster trailer application

A trailer brake application using either the hand valve or the foot valve

Correct! Wrong!

An air leak from the exhaust port of a relay valve in the release position could be caused by a faulty:

Inlet valve seat

Exhaust valve seat

Piston O-ring

Holding valve

Correct! Wrong!

If the trailer emergency line is severed, the trailer brakes will dynamite through the actions of the:

Highway valve

Trailer relay emergency valve

Dash mounted emergency valve

Tractor protection relay valve

Correct! Wrong!

What is not included in the FMVSS 121 regulations?

Toothed wheel rings at each wheel

A toothed wheel ring on the drive shaft

The system to power up when the key switch is turned on

A fail safe mode

Correct! Wrong!

When air pressure in the tractor drops to 50 PSI, air flow through the tractor protection valve:

Stops

Is not affected

Increases

Decreases

Correct! Wrong!

The push rod should not extend past a point of _________ degrees between the push rod and slack adjuster.

50

60

90

110

Correct! Wrong!

A loose mounting between the air governor and air compressor might cause:

An air leak above 60 PSI

System pressure to increase to safety valve pressure

Excessive compressor noise

The wig wag to activate

Correct! Wrong!

On a vehicle equipped with a relay type tractor protection valve, should the trailer service line become disconnected and the brakes are severely applied, what would happen if the tractor pressure dropped to 50 PSI?

The trailer dash valve would pop

The tractor spring brake dash valve would pop

The pressure would continue to drop

The tractor service brakes would cease to function

Correct! Wrong!

If the dash warning light on ABS air brakes fail to go out after the vehicle has been started, indicates a failure in the ABS system and the vehicle should not be driven.

true

false

Correct! Wrong!

ABS air brakes used wheel sensor to monitor wheel speed:

True

False

Correct! Wrong!

If an automatic slack adjuster fails to set up the brake to the required stroke:

It must be replaced

I cannot be set manually

It may not have been installed correctly

replace with a manual slack adjuster

Correct! Wrong!

When a standard air brake system is equipped with a dash mounted control valve labelled "dry road, slippery road," in conjunction with a front wheel "limiting valve," this will allow:

A 50% reduction of application air pressure to the front wheels when the control valve is in the "slippery road" position

A 50% increase of application air pressure to the front wheels when the control valve is in the "dry road" position

A 50% reduction of application air pressure to the front wheels when the control valve is in the "dry road" position

A 50% reduction of application air pressure in a panic stop situation

Correct! Wrong!

Which air source is used to release spring brakes on a dual air system?

Supply

Primary

Secondary

Blended

Correct! Wrong!

On a dual air system, a tractor protection valve uses which of the following?

Supply air

Blended air

Primary air

Secondary air

Correct! Wrong!

Why do you need a highway valve?

To enable you to apply both the trailer and tractor service brakes simultaneously

To enable you to apply tractor service brakes only

To increase the speed of the application of the trailer service brakes

To enable you to apply the trailer service brakes only

Correct! Wrong!

If air pressure builds too high in an air system, what may be wrong?

The governor is causing the unloader to unload

The governor is sending too much pressure to the unloader

The governor is not sending enough air pressure to the unloader

The unloader is stuck open

Correct! Wrong!

If air pressure is lost from the emergency line to a trailer with a relay-emergency valve the trailer would?

Do nothing until a service application is made

Reduce the effective braking by 50%

Apply the service brakes

Send air pressure to the spring brake chambers

Correct! Wrong!

What may cause the parking brakes to release slowly on a trailer?

A faulty relay valve

Trailer reservoirs that are too small

A restricted filter/screen at the spring-brake valve

A faulty highway valve

Correct! Wrong!

What is the purpose of the trailer dash valve?

To apply the tractor and trailer brakes

To apply the trailer brakes

To apply the tractor brakes

To activate the tractor protection valve

Correct! Wrong!

What would happen if the service line ruptured on a trailer?

It would leak when the service brakes were applied

The trailer brakes would dynamite

The tractor spring brakes would apply

The trailer service brakes would apply

Correct! Wrong!

What is the correct angle of push rod to slack adjuster when the brakes are applied?

40 degrees

60 degrees

90 degrees

110 degrees

Correct! Wrong!

When charging an air conditioning system with the vehicle running, adding liquid refrigerant may damage the:

compressor

condenser

receiver/drier

evaporator

Correct! Wrong!

A high pressure condition can result from insufficient air flow across the condenser:

True

False

Correct! Wrong!

When the air conditioning is shut off, the refrigerant will reach a balanced pressure in the complete system:

True

False

Correct! Wrong!

When connecting gauges to a refrigeration system you would connect the low side gauge between the:

Compressor and condenser

Condenser and receiver/drier

Receiver/drier and expansion valve

Evaporator and compressor

Correct! Wrong!

The receiver drier is designed to absorb:

Refrigerant oil

Moisture

Heat

Nitrogen

Correct! Wrong!

What controls the pressure in an A/C evaporator?

compressor

receiver dryer

expansion valve

accumulator

Correct! Wrong!

An automatic transmission will not drive in forward or reverse at an idle. the oil pressure is normal, what may be the problem?

Splines torn off at pump

Low oil level

High oil level

Shift linkage broke off

Correct! Wrong!

In a torque converter when the turbine is turning at almost the same speed as the impeller.

Vortex flow is high and rotary flow is low

Rotary flow is high and vortex flow is low

Rotary and vortex flow are even

The stat-or should be in the stopped position

Correct! Wrong!

When performing a stall test on an automatic transmission and torque converter, the engine RPM exceeds the manufacturer''s specifications by 200 RPM, what may be the problem?

Plugged fuel filters

Damaged impeller blades

Stuck stat-or

Freewheeling stat-or

Correct! Wrong!

When performing a stall test on an automatic transmission and torque converter, the engine RPM is 200 RPM below manufacturer''s specifications, what may be the problem?

Plugged fuel filters

Slipping clutches in the transmission

Damaged impeller blades

Stuck stat-or

Correct! Wrong!

When the face of a pot type pressure plate is resurfaced, what else need resurfacing

The pilot bearing bore

The pilot bearing face

The clutch cover mounting flange

There is no need to resurface anything else

Correct! Wrong!

As a clutch plate wears:

The release bearing moves toward the fork

The release bearing moves away from the fork

The clutch brake will not perform as well

Free pedal will increase

Correct! Wrong!

A transmission is misaligned to the engine, which gear would be most likely to pop out?

high

low

second

reverse

Correct! Wrong!

When shifting a ten speed transmission from low to high range, how do you shift it?

Hydraulically

Manually

Air

Vacuum

Correct! Wrong!

If a clutch master cylinder push rod is too long:

The compensating port would be partially covered

There would be grinding of gears

There would be excessive free pedal

Clutch would engage too soon

Correct! Wrong!

On a fuel injection pump system, what is the purpose of the restricted fitting in the return fuel line at the outlet of the fuel pump?

Counter-shaft bearings

Input shaft bearings

Reverse idler shaft bearings

Worn counter-shaft drive gears

Correct! Wrong!

If a transmission is noisy in all gears except direct, what might be the problem?

Input shaft bearing

Output shaft bearing

Counter-shaft bearing

Pilot bearing

Correct! Wrong!

On a hydraulic clutch system if the clutch linkage to the master cylinder is adjusted too long, what may be the result?

Clutch slipping

Clutch not fully releasing

Too much free-play

Excessive pedal effort

Correct! Wrong!

Clutch brake adjustment, at the pedal, should be approximately

1/4 inch

1/2 inch

1 inch

1 1/2 inches

Correct! Wrong!

If a clutch were adjusted so that the clearance between the release bearing and the clutch brake were to be reduced to 3/8 of an inch the clutch would:

Slip

Not fully release

Vibrate

Destroy the release bearing

Correct! Wrong!

If a clutch brake is set properly and is in good working condition but the input shaft fails to stop properly when the clutch is released (pedal to the floor), what may be the problem?

Too little free play

Worn splines on the input shaft

faulty release bearing

Faulty input shaft bearing

Correct! Wrong!

In the adjacent illustration, what most likely caused this failure?

coasting with the clutch disengaged

excessive slipping

too much clutch brake

misalignment between the engine and transmission

Correct! Wrong!

In the adjacent illustration, what most likely caused this failure?

Coasting with the clutch disengaged

Excessive slipping

Too much clutch brake

Misalignment between the engine and transmission

Correct! Wrong!

In a full time four wheel drive vehicle, or a tandem drive axle truck what is required in the transfer case/power divider?

Differential

High and low range

Planetary gear set

Slip clutch

Correct! Wrong!

The property phase a drive line as illustrated you would:

Turn one end 90 degrees

Turn both ends 90 degrees

Turn both ends 180 degrees

Turn one end 180 degrees

Correct! Wrong!

A vehicle with a lot of drive-line vibration would have:

Uneven working angles

No working angles

Parallel working angles

Even working angles

Correct! Wrong!

A high pitched whine in a differential while under acceleration could be caused by:

Incorrect tooth contact

Too much pinion bearing preload

Faulty spigot bearing

Too much crown/pinion backlash

Correct! Wrong!

In a planetary gear set with the sun held and the carrier driven, what do you have?

Overdrive

Reduction

Neutral

Reverse

Correct! Wrong!

If the sun is held and the carrier is the drive, you have:

Neutral

Reverse

Overdrive

Direct

Correct! Wrong!

In a planetary gear set if the ring gear is held, the carrier is the drive and the sun is driven the result is:

Forward reduction

Forward overdrive

Reverse reduction

Reverse overdrive

Correct! Wrong!

In the following illustration, if the clutch is engaged at A and released at B what gear is the gear set in?

Forward reduction

Forward overdrive

Direct

Reverse

Correct! Wrong!

In the adjacent illustration, increasing this amount will move the pattern:

Toward the root of the tooth

Toward the crown of the tooth

Toward the heel

Toward the toe

Correct! Wrong!

If a differential assembly is noisy on turns only, one of the causes might be:

A loose pinion in the housing

Worn differential

Wrong axle splines

Worn crown and pinion

Correct! Wrong!

To determine the pinion bearing preload:

Take the spring scale reading while the housing is rotating

Take the spring scale reading when the housing first starts to rotate

Multiply the scale reading times the diameter of the bearing cage

Divide the scale reading by the diameter of the cage

Correct! Wrong!

Pinion depth is increased or decreased by:

Different bearing spacer thickness

Adding or subtracting shims

Moving the threaded adjusters

Varying the torque on the yoke nut

Correct! Wrong!

An inter-axle differential in the normal running position will:

Drive only the front axle

Divide torque equally between the axles

Drive only the rear axle

Have differential action

Correct! Wrong!

Phasing of a drive shaft refers to:

Yoke alignment

Working angles

Grease fitting alignment

Knuckling action

Correct! Wrong!

The two methods of drive line alignment are the parallel method and:

Interesting line method

Vertical line method

Constant velocity method

Horizontal method

Show hint

Correct! Wrong!

For good cancellation, working angles should be no more than ___________ degrees difference on a drive shaft.

1

3

5

7

Correct! Wrong!

When checking an electronic speedometer pick-up, what should your meter be set to?

Ohms

Amps

Volts

Continuity

Correct! Wrong!

Ohmmeter ratings on a good diode should read:

Continuity in both directions

Infinity in both directions

Infinity in one direction and continuity in the other

500 Ohms in both directions

Correct! Wrong!

How will the following illustrated system operate if the resistor at A breaks: (becomes open)?

The motor will only operate on high speed

The motor will not operate at all

The motor will run normally in all positions except low

The motor will burn out if rm in the low position

Correct! Wrong!

Which of the following symbols indicate an item that will protect an electrical circuit?

A

B

C

D

Correct! Wrong!

What is the advantage of putting a relay in a headlight circuit?

It protects the circuit

It reduces headlight failure

There is less current flow at the switch

There is more current flow at the switch

Correct! Wrong!

If resistance is doubled while the voltage remains the same:

Current will remain the same

Electromotive force will be cut in half

Current flow will double

Current flow will be cut in half

Correct! Wrong!

When checking the signal lights on a truck a technician finds that the left turn signal works fine but the right side does not flash, only the indicator light comes on and stays on. The most likely problem with the system might be:

Faulty flasher

Poor ground on one of the signal light bulbs

Short in the wiring to one of the right signal lights

Grounded flasher

Correct! Wrong!

In the following illustration what is being tested?

Reluctor

Magnetic pick-up

Cam angle

Dwell

Correct! Wrong!

In the adjacent illustration, what is being tested?

Primary circuit

Secondary circuit

Dwell

Coil output

Correct! Wrong!

Reverse polarity of the coil primary winding will cause:

Higher secondary voltage requirement

Lower secondary voltage requirement d.

Burnt contact points

Detonation

Correct! Wrong!

If the spark plug nose insulator is greyish in color or is blistered:

Install hotter running plugs

Install cooler running plugs

Reduce the dwell angle

Advance the ignition timing

Correct! Wrong!

To adjust dwell in a distributor which uses electronic ignition, the breaker plate would be moved opposite to distribute rotation.

True

False

Correct! Wrong!

After changing a turbocharger, a technician should:

Run the engine at an idle

Run the engine at half throttle

Check for pieces in the exhaust pipe

Check for pieces in the intake

Correct! Wrong!

At which location do you measure cam ground pistons?

Across the crown at 90 degrees to the pin bosses

Across the crown in line with the pin bosses

Across the skirt at 90 degrees to the pin bosses

Across the skirt in line with the pin bosses

Correct! Wrong!

Where should ring gap be measured on a deg-lazed liner?

Near the top of the ring travel area

Near the center of the ring travel area

Near the bottom of the ring travel area

Ring gap can be measured in all areas of ring travel

Correct! Wrong!

If a dry sleeve goes in too tight the result will be:

Excessive piston to liner clearance

Distortion of the sleeve

Increased ring end gap

Poor heat transfer between the sleeve and block

Show hint

Correct! Wrong!

What is the characteristic of a Roots type blower?

Volume increases with RPM

Volume increases with boost pressure

Volume increases with fuel increase

Volume is constant through all speed and torque ranges

Correct! Wrong!

The purpose of removing air box covers on a Detroit Diesel engine is to:

Inspect for blowby

Inspect for wrist pin end play

Inspect the condition of the piston rings

Inspect the engine for excessive oil consumption

Show hint

Correct! Wrong!

If a valve seat is not installed low enough in the head what will result:

Clearance volume will be decreased

The piston will contact the valve

The valve will not cool properly

Valve spring tension will be reduced

Correct! Wrong!

Why are lifters offset on a camshaft?

Quieter operation

To reduce flutter at higher RPM

To reduce wear

To rotate the lifters

Show hint

Correct! Wrong!

What does a limiting speed governor control?

Fuel control through the complete RPM range

Idle and high idle RPM

High idle RPM only

Peak torque

Correct! Wrong!

What happens if a full flow oil filter becomes plugged?

The oil pressure will drop by approximately 5-10 PSI

The filter will blow up

The engine will seize

The oil pressure will go to a dangerous level

Correct! Wrong!

If an engine coolant water pump impeller is installed too far away from the housing it will:

Tear out the bearing

Contact the housing

Cause the engine to overheat

Put excessive pressure on the seal

Correct! Wrong!

What would cause oil to appear in the turbo crossover to the intake manifold?

Worn piston rings

Excessive oil pressure

Restricted exhaust pipe

Faulty turbo seals

Correct! Wrong!

Where is the emergency shut down on a Detroit Diesel?

Before the turbo

After the blower

Before the blower

At the governor

Correct! Wrong!

When grinding valves and seats, if a valve lap mark is too close to the margins of the valve:

Lower the seat by using a 15 degree stone

Raise the seat by using a 45 degree stone

Replace the valve

Replace the seat

Correct! Wrong!

When grinding valves and seats and restoring or replacing valve guides, the correct order of service is:

Valve then seat then guide

Seat then valve then guide

Guide then valve then seat

The order is not important

Correct! Wrong!

Valve springs should be checked for:

Tension and free length

Squareness

Stretch

Both A and B

Correct! Wrong!

A cam ground piston is narrower across the:

Sides that are 90 degrees from the wrist pin bosses

Wrist pin bosses

Skirt then the crown

Both A and C

Correct! Wrong!

The main difference between a gasoline engine and a diesel is in the:

Weight of the engine

Firing order

Combustion process and engine speed control

Number of strokes per cycle

Correct! Wrong!

What might be the problem with a diesel engine that has an increase in power and excessive smoke?

Plugged air cleaner

Plugged fuel filters

Faulty turbo charger

Restricted fuel return line

Show hint

Correct! Wrong!

On a 6 cylinder in-line engine, (firing order 153624) if #1 is firing, what is #3 doing?

Intake

Compression

Power

Exhaust

Correct! Wrong!

The likely cause of a broken crankshaft near the front of an engine could be:

Incorrect engine and transmission alignment

Damage or inoperative harmonic balancer

Worn main bearings

Front connecting rod bearing wear

Correct! Wrong!

Valve overlap is the total degrees of duration:

Of the intake

Including clearance ramps

While both exhaust and intake valves are open

While both exhaust and intake valve are closed

Correct! Wrong!

Bearing crush is best defined as:

Adjustment of the bearing clearance

Adjustment of the fit of the bearing to the crankshaft

Protrusion of the bearing shell above the parting face of the cap or the rod

The damage caused by over-torquing the bearing cap bolts

Correct! Wrong!

Excessive crankshaft end clearance could cause:

The pistons to scuff

The timing gears to whine

Main bearing knock

Wrist pin rattle

Correct! Wrong!

A surge tank in a cooling system is used to:

Eliminate the need for cooling system pressure

Eliminate the need for a thermostat

Add to the cooling capacity of the radiator

Reduce cooling system aeration

Correct! Wrong!

A cooling system that operates with a 10 lb. radiator cap will have

A coolant boiling temperature of 242 degrees F

A coolant boiling temperature of 222 degrees F

A lower operating temperature than a 6 lb. cap

A coolant boiling temperature of 202 degrees F

Correct! Wrong!

Glycol based anti freeze in the oil will:

Evaporate from the oil at operating temperature

Be filtered out by the oil filter

Act as a lubricant

Form varnish under heat and damage the engine

Correct! Wrong!

High air box pressure in a Detroit Diesel, two stroke cycle engine could be caused by:

A plugged air cleaner

A faulty fuel setting

Restricted exhaust

Blower overspeed

Correct! Wrong!

The instrument used to measured exhaust temperature is the:

Manometer

Pyrometer

Refractometer

Hydrometer

Correct! Wrong!

Excessive black smoke under load could be caused by:

Excessive boost pressure

Leaking head gasket

Restricted fuel supply

Engine overfueling

Correct! Wrong!

Burned or damaged pistons in a diesel engine could be caused by:

Restricted air inlet

Worn injector orifices

Low injection pressures

Pre-ignition

Correct! Wrong!

When checking turbocharger boost pressure the engine should:

Be operated with the transmission in neutral

Have the air filter removed

Have the inlet chilled with dry ice

Be under maximum load

Correct! Wrong!

To improve combustion, all diesel engines use:

Air turbulence

Turbulence chambers

Pre-combustion chambers

Fuel turbulence

Correct! Wrong!

Loose Cummins injector adjustment will cause:

Fast engine acceleration

Black smoke and car-boning of injector tips

High fuel pump pressure

Tappet noise

Correct! Wrong!

To adjust the valves and injectors on a Cummins engine, position on:

Valve overlap for that cylinder

TDC for that cylinder

The intake stroke

The VS marks

Correct! Wrong!

Caterpillar capsule type injectors are adjusted:

On the VS mark

At TDC

At the factory

When the exhaust valves are open

Correct! Wrong!

A seized CAT injection pumping unit will cause:

The engine to stop

Two cylinders to misfire

The rack to immediately go to full fuel

Faulty fuel control and misfiring on one cylinder

Correct! Wrong!

Detroit Diesel injectors should be timed when:

The injector plunger is down

On the VS mark

The piston is at BDC

The valves are fully open

Correct! Wrong!

A leaking injector fuel return tube on a Detroit Diesel engine would cause:

That cylinder to misfire

Too much fuel to recirculate to the tank

Fuel dilution of the engine oil

Black smoke

Correct! Wrong!

A mechanical governor operates on the principle of:

Spring tension and flyweight speed

Intake manifold pressure and spring tension

Intake manifold pressure and flyweight speed

turbo speed and spring tension

Correct! Wrong!

A fifth wheel should be adjusted:

Tight to the pin

King pin dimension with the jaws open

King pin dimension with the jaws closed

While hooked to a trailer

Correct! Wrong!

Which of the following is the correct frame repair procedure?

Weld the crack and fish-plate

Drill a hole at the end of the crack, weld the crack and reinforce

Fish plate the crack

Weld up the crack

Correct! Wrong!

When repairing a cracked frame rail:

Drill a hole at the end of the crack and weld a reinforcement plate over the crack

Drill a hole at the end of the crack and bolt a reinforcement plate over the crack

Drill a hole at the end of the crack, V and weld up the crack then reinforce

V and weld the crack

Correct! Wrong!

When unlike metals are fastened together:

They must be welded only

They must first be painted or coated

Round head carriage bolts must be used

They must be the same weight

Correct! Wrong!

The first step when inspecting a frame for defects is to:

Block it up

Check air pressure in tires

Clean the frame thoroughly

Drive the vehicle over rough ground

Correct! Wrong!

An example of a monocoque frame would be:

Truck

Bus

High-boy

Low-boy

Correct! Wrong!

Progressive rate springs:

Are always used in front suspension systems

Serve their best purpose in rear suspension systems

Are only used on loader type suspension systems

Are only used on grader type suspension systems

Correct! Wrong!

What is the name of the gas used in hydro-air suspension?

Air

Hydrogen

Oxygen

Nitrogen

Correct! Wrong!

Leaf spring center bolts are:

An indication of the dead center of the spring

Used to fasten the spring to the axle

Used to align and center spring leaves to themselves and the axle

A "back-up" fastener in case spring rear shackle bolt brakes

Correct! Wrong!

The parallel string method of checking frame alignment does not check for:

Frame twists

Non-parallel rails

Diamonding

All of the above

Correct! Wrong!

On rubber block suspension, to check condition of the offset/drive pin brackets and bushings you would:

Jack up the beam

Measure height of rubber block

Turn a sharp corner

Take weight off the frame

Correct! Wrong!

All spring packs use a centre bolt to locate the spring to the axle or trunion

True

False

Correct! Wrong!

Equalizer beams

Support the load on the axle

Support the load on two axles

Maintain correct drive line angles

Transfer the load to the inside wheels on corners

Correct! Wrong!

Torque rods

Flex with engine torque

Increase the load to the inside wheels on corners

Support the load on the wheels

Maintain correct drive the alignment

Correct! Wrong!

What might be damaged by lifting the frame on an air ride suspension?

Trailing arm

U-bolts

Air bellows

Leveling valve

Correct! Wrong!

On an air ride system what does the leveling valve do?

Keeps the vehicle level at all times

Maintains equal pressure in all the bag

Prevents sway

Maintains a predetermined ride height

Correct! Wrong!

A broken main spring leaf with the crack extending across the center bolt hole would be an indication that the:

Shock absorbers are faulty

Vehicle has been overloaded

Spring leaf was made from inferior material

U-bolts were loose

Correct! Wrong!

The device that prevents semi-elliptical spring leaves from excessive separation when a wheel drops in a hole is called a(n):

Center bolt

Rebound clip

Torque arm

Torsion bar

Correct! Wrong!

What is the purpose of a venturi in a carburetor?

Increases air velocity

Creates a partial vacuum

Reduces flow restriction

Aids in the starting of a vehicle

Correct! Wrong!

A Caterpillar transfer pump:

Pumps more fuel than is required by the engine

Pumps just as much fuel as required by the engine

Is centrifugal

Is only required in order to prime the filters

Correct! Wrong!

What does cetane stand for?

The ability of the fuel to resist knock

The ability to the fuel to resist ignition

The ability to the fuel to burn cleanly

The ability of the fuel to ignite

Correct! Wrong!

A gasoline with a high octane rating

Will detonate easier

Will cause pre-ignition

Will cause the engine to ping

Will reduce knock

Correct! Wrong!

What is the correct thing to do when disconnecting a gasoline fuel injection line?

Wear safety glasses

Bleed the pressure down

Cool the engine

Remove the fuel tank cap

Correct! Wrong!

In a carburetor, a low float level would result in:

A lean mixture

Better fuel economy at the expense of power

A rich mixture

Engine overheating

Correct! Wrong!

The lower the octane rating of gasoline:

The harder it is to ignite

The lower its heat content

The easier it is to ignite

The less it resists combustion knock

Correct! Wrong!

In an Cummins engine using a mechanical injector, how would you check for an engine miss?

Hold the injector plunger down on each cylinder (one at a time) while the engine is running

Crack each fuel line to the nozzles (one at a time) while the engine is running

Perform a compression test on each cylinder to see which is the low one

Disconnect the glow plug wire from each cylinder (one at a time) to see which one is missing

Correct! Wrong!

To check which cylinder is missing on an engine equipped with an inline injection pump and nozzles in the cylinder head, you would:

Hold the injector plunger down on each cylinder (one at a time) while the engine is running

Crack each fuel line to the nozzles (one at a time) while the engine is running

Perform a compression test on each cylinder to see which is the low one

Disconnect the glow plug wire from each cylinder (one at a time) to see which one is missing

Correct! Wrong!

On gasoline engine equipped with an EGR valve the valve opens and

Re-circulates exhaust gases back through the carburetor

Recirculates exhaust gases through the charcoal canister

Recirculates exhaust gases through the intake manifold

Allows exhaust gases to escape to the atmosphesre

Correct! Wrong!

Which type of fuel system uses a cam ring and plungers to pressurize the fuel

Cummins type

Detroit type

Cat type

Distributor type

Correct! Wrong!

Pintle type nozzles are used with:

Direct injection

Pre-combustion chambers

Electronic fuel injection

Two stroke cycle engines

Correct! Wrong!

A distributor type pump uses a ___________________ to control the delivery rate.

Rack and rotating plungers

Fuel pressure regulator

Port and helix

Metering valve

Correct! Wrong!

The purpose of the residual check valve in a hydraulic brake system is to:

Reduce lag time of drum brakes

Prevent air from entering the system

Reduce lag time of disc brakes

Both A and B

Correct! Wrong!

If all the brakes drag on a vehicle the most likely cause would be

Incorrectly adjusted push rod to master cylinder

Water in brake fluid

Failure to install a residual check valve

Plugged replenishing port

Correct! Wrong!

What is responsible for causing the pads to move away from the rotors on a disc brake system

Return springs

Returning fluid velocity

Rotor parallelism

Caliper piston seal

Correct! Wrong!

Which item would be faulty if brake fluid were to leak out of the firewall side of the master cylinder?

Primary cup on the secondary piston

Primary cup on the primary piston

Secondary cup on the secondary piston

Secondary cup on the primary piston

Correct! Wrong!

If a rotor had faulty parallelism what drive-ability problem may be incurred?

Pedal pulsation

Dragging brakes

Squealing brakes

Wheel lock up

Correct! Wrong!

On a hydraulic brake system, what are the forms of power assist failure backup?

Hydro-boost and accumulator

Hydro-boost and electric motor driven pump

Electric motor driven pump and accumulator

Hydrovac and electric motor driven pump

Correct! Wrong!

What should be used to clean internal hydraulic brake parts?

Solvent

Carburetor cleaner

Brake fluid and denatured alcohol

Gasoline

Correct! Wrong!

Performing a check of a vacuum booster on a hydraulic brake system should result in the pedal:

Moving down slightly during application when the engine is started

Moving up slightly during application when the engine is started

Not moving during application when the engine is started

Moving down then up during application when the engine is started

Correct! Wrong!

What is the purpose of a metering valve in a hydraulic brake system?

To reduce braking effort to the rear wheels

To increase braking effort to the front wheels

To match braking effort of front disc and rear drum brakes

To match braking effort of vehicles with four wheel disc brakes

Correct! Wrong!

The difference between an unbalanced vane pump and a balanced vane pump is the:

Direction of rotation

Type of oil used

Inlet and outlet vanes

Number of inlet and outlet ports

Correct! Wrong!

Cavitation could occur when:

Engine speed is too low

System pressure is adjusted too high

Return line filters are plugged

Oil viscosity is too high

Correct! Wrong!

A pneumatic accumulator is filled with:

Argon

Air

Nitrogen

Oxygen

Correct! Wrong!

An open center system can bet be described as on in which:

Pump oil flow is not circulated

Pump delivery recirculates freely to the pump inlet in the neutral position

Pump delivery is not unloaded to the reservoir in the neutral position

Pump delivery recirculates freely to the reservoir in the neutral position

Correct! Wrong!

A four connection (four way) spool valve is used in conjunction with a:

Double acting cylinder

Single acting cylinder

Telescopic ram

Ram type cylinder

Correct! Wrong!

Viscocity can best be described by:

A small fluctuation of fluid pressures

A small amount of fluid flow

The velocity of fluid flow

The resistance to fluid flow

Correct! Wrong!

The pump inlet size should:

Match the driven end of the pump

Be larger that the outlet

Be smaller than the outlet

Be the same size as the cylinder lines

Correct! Wrong!

The most likely cause of decreased hydraulic actuator speed would be:

Low oil level

Lack of pump pressure

Decreased oil flow

Excessive pump pressure

Correct! Wrong!

The force developed by a cylinder is calculated by:

Pressure times the piston area

Pressure times the cylinder length

Flow times pressure

Flow times the piston area

Correct! Wrong!

The dash number used for sizing hydraulic hose refers to its inner diameter in:

8th''s of an inch

16th''s of an inch

32nd''s of an inch

64th''s of an inch

Correct! Wrong!

When making up a hose that requires the end to be skived to install the replaceable fitting, the amount skived is:

Two times the diameter of the fitting

1/2 diameter of the hose

The length up to the notch on the fitting socket

The length of the fitting

Correct! Wrong!

Flow rate is best defined as:

A measure of the volume of fluid that passes a given point in a given time

A measure of the speed of fluid that passes a given point in a given time.

The average speed of a fluid past a given point.

Viscosity of liquid in motion

Correct! Wrong!

In a system with a variable displacement pump, the volume of the fluid moved by the pump will:

Decreased when the system pressure drops

Stay the same when the system pressure drops

Increase when the system pressure drops

Move to zero

Correct! Wrong!

A cylinder tends to creep when stopped in mid-stroke, the control valve checked out as operational and there is no external leakage, the next thing to check for would be:

High viscosity oil

Internal leakage

Pump output

System pressure

Correct! Wrong!

A fire referred to as a Class B would occur in:

Flammable liquids

Electrical equipment

Ordinary flammables

Flammable metals

Correct! Wrong!

Worker's Compensation regulations state that the tool-rest on a bench grinder should be no further away from the grinding wheel than:

1/16 of an inch

1/8 of an inch

1/4 of an inch

3/8 of an inch

Correct! Wrong!

A telescoping gauge is used for measuring the:

Circumference of a circular part

Diameter of a hole

Thickness of a square part

Depth of a bore

Correct! Wrong!

In the adjacent figure, the reading on the 0 to 1 inch outside micrometer:

0.376

0.221

0.246

2.416

Correct! Wrong!

An engine having a original bore size of 4 3/8 inches is rebored .030 oversize. The resulting bore size is:

4.405

4.530

4.430

4.675

Correct! Wrong!

Acetylene hose fittings are:

Pipe thread

Left hand thread

Right hand thread

Interchangeable with oxygen fittings

Correct! Wrong!

The tap generally used to first cut threads in a drilled hole is the:

Taper tap

Plug tap

Bottoming tap

Spiral tap

Correct! Wrong!

A JIC connection is flared at an angle of:

27 degrees

37 degrees

45 degrees

47 degrees

Correct! Wrong!

Pipe size is generally measured by the:

Inside diameter

Outside diameter

Wall thickness

Pitch of the thread

Correct! Wrong!

If you use a hammer and a punch to install a bearing on a tight shaft and inside a tight bore damage to the bearing roller or ball raceways may result in the form of:

Flaking

Spalling

Etching

Brinnelling

Correct! Wrong!

Only when full fielding the alternator does the output meet the alternator rating, what may be the problem?

Faulty regulator

Slipping belts

Low battery

Bad diodes in rectifier

Correct! Wrong!

To polarized a B type generator

Ground the armature lead

Ground the field lead

Disconnect the generator field lead at the regulator and momentarily connect it to the battery terminal

Momentarily connect the regulator battery terminal to the armature terminal

Correct! Wrong!

A sulphated battery can be caused by:

High charging voltage

High charging amperage

Deep cycling

Leaving a battery in a discharged state for a long period of time

Correct! Wrong!

The cells in a battery are normally connected in:

Parallel

Series

Series parallel

Pairs

Correct! Wrong!

With little or no current draw and no starter rotation the most likely cause would be:

Defective starter drive

Grounded armature

Worn armature bushings

An open circuit

Correct! Wrong!

To prevent overheating of the starter motor, cranking time should not exceed:

30 seconds

45 seconds

60 seconds

120 seconds

Correct! Wrong!

On a vehicle equipped with a good series parallel switch, leaving the lights on with the engine stopped will:

Discharged the A battery

Discharged the B battery

Discharged both the A and B batteries

Discharge either the A or B battery depending on the position of the starter

Correct! Wrong!

When testing an alternator rotor your ohmeter reads "0" is this acceptable?

Yes

No

Correct! Wrong!

What is the cause of wheel tramp?

Static balance

Dynamic balance

Faulty shocks

Faulty springs

Correct! Wrong!

A cause of steering pulling in one direction would be

Incorrect toe

Too much toe out on turns

Uneven tire pressures

Tight king pins

Correct! Wrong!

A cause for steering to wander would be incorrect:

Toe setting

Caster setting

Camber

King pin inclination

Correct! Wrong!

Feather edging of tires is caused by excessive:

Camber

Caster

Toe

KPI

Correct! Wrong!

Misaligned drive axles, will cause steering axle tires to wear:

True

False

Correct! Wrong!

The use of tapered wheel bearing provides for:

Axial loading

Radial loading

Both A and B

Correct! Wrong!

Leakage of the sector shaft seal (near the pitman arm) on a power steering box might be caused by:

Excessive pump pressure

Steering box not centered

Lost motion in the steering linkage

High return pressure

Correct! Wrong!

The assembly that supports a track machine is called:

A flotation unit

A final drive unit

An undercarriage

A body

Correct! Wrong!

Mechanic A says that track frames may be made of box or channel steel. Mechanic B says that track frames are kept in alignment with a diagonal brace. Who is right?

A is right

B is right

Both are right

Neither is right

Correct! Wrong!

The purpose of a recoil mechanism is to:

Assist in the alignment of the rollers

Take up the shock of the first gear engagement

Provide a place for mounting working attachments

Act as a shock absorber for the undercarriage

Correct! Wrong!

Mechanic A says that the hydraulic track adjuster uses hydraulic fluid from the transmission for operation. Mechanic B says that front idlers are attached directly to the final drive unit. Who is right?

A is right

B is right

Both are right

Neither is right

Correct! Wrong!

Bolt on segments are preferred over spoke sprockets because

Last longer

Are easier to replace

Have smaller teeth

Ar stronger

Correct! Wrong!

If a track chain uses two conical washers installed back-to-back in the link counter bore they are called sealed chain.

True

False

Correct! Wrong!

The best shoe for use in areas where traction is important would be

Flat shoes

Standard grouser

Open shoes

Triple grouser

Correct! Wrong!

The high drive system described in the text has

Four major bogies

Two major bogies

Only minor bogies

Torsion bar springs

Correct! Wrong!

To control the movement of the major bogies, the suspension system uses

Inner and outer collars

rubber pads

Lubricated pins

A equalizer bar

Correct! Wrong!