Powerplant-Engine Lubrication Systems

What is the primary purpose of the fuel/ oil heat exchanger?

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Cool the fuel.

Cool the oil.

De-aerate the oil.

Cool the oil.

Possible failure related ferrous-metal particles in turbine engine oil cause an (electrical indicating-type magnetic chip detector to indicate their presence by

disturbing the magnetic lines of flux around the detector tip.

bridging the gap between the detector center (positive) electrode and the ground electrode.

generating a small electric current that is caused by the particles being in contact with the dissimilar metal of the detector tip.

bridging the gap between the detector center (positive) electrode and the ground electrode.

In a reciprocating engine oil system, the temperature bulb senses oil temperature

ANSWERS

at a point after the oil has passed through the oil cooler.

while the oil is in the hottest area of the engine.

immediately before the oil enters the oil cooler.

at a point after the oil has passed through the oil cooler.

The purpose of directing bleed air to the outer turbine case on some engines is to

ANSWERS

provide optimum turbine blade tip clearance by controlling thermal expansion.

provide up to 100 percent kinetic energy extraction from the flowing gases.

allow operation in a thermal environment 600 to 800°F above the temperature limi of turbine blade and vane alloys.

provide optimum turbine blade tip clearance by controlling thermal expansion.

Some larger reciprocating engines use a compensating oil pressure relief valve to 8

ANSWERS

provide a high engine oil pressure when the oil is cold and automatically lower the oil warms up

compensate for changes in atmospheric pressure that accompany altitude changes.

automatically keep oil pressure nearly the same whether the oil is warm or cold.

provide a high engine oil pressure when the oil is cold and automatically lower the oil warms up

The engine oil temperature regulator is usually located between which of the following a dry sump reciprocating engine?

ANSWERS

The engine oil supply pump and the internal lubrication system.

The scavenger pump outlet and the oil storage tank.

The oil storage tank and the engine oil supply pump.

The scavenger pump outlet and the oil storage tank.

The purpose of a dwell chamber in a turbine engine oil tank is to provide

ANSWERS

a collection point for sediments.

for a pressurized oil supply to the oil pump inlet.

separation of entrained air from scavenged oil.

separation of entrained air from scavenged oil.

Where are sludge chambers, when used in aircraft engine lubrication systems, usually located?

ANSWERS

In the crankshaft throws.

Adjacent to the scavenger pumps.

In the oil storage

In the crankshaft throws.

What type of oil do most engine manufacturers recommend for new reciprocating engine break-in?

ANSWERS

Ashless dispersant oil.

Straight mineral oil.

Semi-synthetic oil.

Straight mineral oil.

The main oil filters strain the oil at which point in the system?

ANSWERS

Immediately after it leaves the scavenger pump.

Immediately before it enters the pressure pump.

Just as it leaves the pressure pump.

Just as it leaves the pressure pump.

What prevents pressure within the lubricating oil tank from rising above or falling below ambient pressure (reciprocating engine)?

ANSWERS

Oil tank check valve.

Oil pressure relief valve.

oil tank vent.

oil tank vent.

Why is an aircraft reciprocating engine oil tank on a dry sump lubrication system equipped with a vent line?

ANSWERS

To prevent pressure buildup in the reciprocating engine crankcase.

To eliminate foaming in the oil tank.

To prevent pressure buildup in the oil tank.

To prevent pressure buildup in the oil tank.

The purpose of a relief valve installed in the tank venting system of a turbine engine oil tank is to

ANSWERS

prevent oil pump cavitation by maintaining a constant pressure on the oil pump inlet.

maintain internal tank air pressure at the ambient atmospheric level regardless of altitude or rate of change in altitude.

maintain a positive internal pressure in the oil tank after shutdown to prevent oil pump cavitation on engine start.

prevent oil pump cavitation by maintaining a constant pressure on the oil pump inlet.

The vent line connecting the oil supply tank and the engine in some dry sump engine installations permits

ANSWERS

pressurization of the oil supply to prevent cavitation of the oil supply pump.

oil vapors from the engine to be condensed and drained into the oil supply tank.

the oil tank to be vented through the normal engine vent.

the oil tank to be vented through the normal engine vent.

The vent line connecting the oil supply tank and the engine in some dry sump engine

installations permits

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pressurization of the oil supply to prevent cavitation of the oil supply pump.

oil vapors from the engine to be condensed and drained into the oil supply tank.

the oil tank to be vented through the normal engine vent.

the oil tank to be vented through the normal engine vent.

An oil separator is generally associated with which of the following?

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Engine-driven oil pressure pump.

Engine-driven vacuum pump.

Cuno oil filter.

Engine-driven vacuum pump.

What would be the probable result if the oil system pressure relief valve should stick in the open position on a turbine engine?

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Increased oil pressure.

Decreased oil temperature.

Insufficient lubrication.

Insufficient lubrication.

What prevents pressure within the lubricating oil tank from rising above or falling below ambient pressure (reciprocating engine)?

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0il tank check valve.

Oil pressure relief valve.

Oil tank vent.

Oil tank vent.

Why is an aircraft reciprocating engine oil tank on a dry sump lubrication system equipped with a vent line?

Answer Choices

to prevent pressure buildup in the reciprocating engine crankcase.

To eliminate foaming in the oil tank.

To prevent pressure buildup in the oil tank.

To prevent pressure buildup in the oil tank.

An engine lubrication system pressure relief valve is usually located between the

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oil cooler and the scavenger pump.

scavenger pump and the external oil system.

pump and the internal oil system.

pump and the internal oil system.

What is the source of most of the heat that is absorbed by the lubricating oil in a reciprocating engine?

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Crankshaft main bearings.

Exhaust valves.

Pistons and cylinder walls.

Pistons and cylinder walls.

The pumping capacity of the scavenger pump in a dry sump aircraft engine's lubrication system

is greater than the capacity of the oil supply pump.

is less than the capacity of the oil supply pump.

is usually equal to the capacity of the oil supply pump in order to maintain constant oiling conditions.

is greater than the capacity of the oil supply pump.

If the oil in the oil cooler core and annular jacket becomes congealed, what unit prevents damage to the cooler?

Oil pressure relief valve.

Airflow control valve.

Surge protection valve.

Surge protection valve.

Which of the following helps determine the proper grade of oil to use in a particular

Adequate lubrication in various attitudes of flight.

Positive introduction of oil to the bearings.

Operating speeds of bearings.

Operating speeds of bearings.

At cruise RPM, some oil will flow through the relief valve of a gear-type engine oil pump. This is normal as the relief valve is set at a pressure which is

lower than the pump inlet pressure.

lower than the pressure pump capabilities.

higher than pressure pump capabilities.

lower than the pressure pump capabilities.

An engine lubrication system pressure relief valve is usually located between the

oil cooler and the scavenger pump

scavenger pump and the external oil system.

pump and the internal oil system.

pump and the internal oil system.

What would be the probable result if the oil system pressure relief valve should stick in the open position on a turbine engine?

Increased oil pressure.

Decreased oil temperature.

Insufficient lubrication.

Insufficient lubrication.

The engine oil temperature regulator is usually located between which of the following on a dry sump reciprocating engine?

The engine oil supply pump and the internal lubrication system.

The scavenger pump outlet and the oil storage tank.

The oil storage tank and the engine oil supply pump.

The scavenger pump outlet and the oil storage tank.

What type of oil do most engine manufacturers recommend after new reciprocating engine break-in?

Metallic-ash detergent oil.

Ashless dispersant oil.

Straight mineral oil.

Ashless dispersant oil.

What type of oil do most engine manufacturers recommend for new reciprocating engine break-in?

Ashless dispersant oil.

Straight mineral oil.

Semi-synthetic oil.

Straight mineral oil.

Oil accumulation in the cylinders of an inverted in-line engine and in the lower cylinders of radial engine is normally reduced or prevented by

reversed oil control rings.

routing the valve-operating mechanism lubricating oil to a separate scavenger pump.

extended cylinder skirts.

extended cylinder skirts.

Why is an aircraft reciprocating engine oil tank on a dry sump lubrication system equipped with a vent line?

To prevent pressure buildup in the reciprocating engine crankcase.

To eliminate foaming in the oil tank.

To prevent pressure buildup in the oil tank.

To prevent pressure buildup in the oil tank.

Which of the following factors has the least effect on the oil consumption of a specific engine?

Answer Choices

Mechanical efficiency.

Engine RPM.

Lubricant characteristics.

Mechanical efficiency.

Which of the following bearing types must be continuously lubricated by pressure oil?

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Ball.

Roller.

Plain.

Plain

High tooth pressures and high rubbing velocities, such as occur with spur-type gears, require the use of

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an EP lubricant.

straight mineral oil.

metallic ash detergent oil.

an EP lubricant.

In an axial-flow turbine engine, compressor bleed air is sometimes used to aid in cooling the

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fuel.

inlet guide vanes.

turbine, vanes, blades, and bearings.

turbine, vanes, blades, and bearings.

In a reciprocating engine oil system, the temperature bulb senses oil temperature

Answer Choices

at a point after the oil has passed through the oil cooler.

while the oil is in the hottest area of the engine.

immediately before the oil enters the 0il cooler.

at a point after the oil has passed through the oil cooler.

An oil separator is generally associated with which of the following?

Answer Choices

Engine-driven oil pressure pump.

Engine-driven vacuum pump.

Cuno oil filter.

Engine-driven vacuum pump.

Why is an aircraft reciprocating engine 0il tank on a dry sump lubrication system equipped with a vent line?

Answer Choices

To prevent pressure buildup in the reciprocating engine crankcase.

To eliminate foaming in the oil tank.

To prevent pressure buildup in the oil tank.

To prevent pressure buildup in the oil tank.

What is the purpose of the check valve generally used in a dry sump lubrication system?

Answer Choices

To prevent the scavenger pump from losing its prime.

To prevent the oil from the supply tank from seeping into the crankcase during inoperative periods.

To prevent the oil from the pressure pump from entering the scavenger system.

To prevent the oil from the supply tank from seeping into the crankcase during inoperative periods.

What is the purpose of the check valve generally used in a dry sump lubrication system?

Answer Choices

To prevent the scavenger pump from losing its prime.

To prevent the oil from the supply tank from seeping into the crankcase during inoperative periods.

To prevent the oil from the pressure pump from entering the scavenger system.

To prevent the oil from the supply tank from seeping into the crankcase during inoperative periods.

What is the primary purpose of changing aircraft engine lubricating oils at predetermined periods?

Answer Choices

The oil becomes diluted with gasoline washing past the pistons into the crankcase.

The oil becomes contaminated with moisture, acids, and finely divided suspended solid particles.

Exposure to heat and oxygen causes a decreased ability to maintain a film under load.

The oil becomes contaminated with moisture, acids, and finely divided suspended solid particles.

After making a welded repair to a pressurized-type turbine engine oil tank, the tank should be pressure checked to

Answer Choices

not less than 5 psi plus the maximum operating pressure of the tank.

not less than 5 psi plus the average operating pressure of the tank.

5 psi.

not less than 5 psi plus the maximum operating pressure of the tank.

Oil tank fillers on reciprocating engines are marked with the word

Answer Choices

"oil" and tank capacity, in accordance with 14 CFR Part 45.

"oil, " type, and grade, in accordance with 14 CFR Part 33.

"oil," in accordance with 14 CFR part 25.

“oil," in accordance with 14 CFR part 25.

What is the source of most of the heat that is absorbed by the lubricating oil in a

reciprocating engine?

Answer Choices

Crankshaft main bearings.

Exhaust valves.

Pistons and cylinder walls.

Pistons and cylinder walls.

Which of the following prevents oil from entering the main accessory case when the engine

is not running?

Answer Choices

Pressure valve.

Hydraulic fuse.

Check valve.

Check valve.

The purpose of the flow control valve in a reciprocating engine oil system is to

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direct oil through or around the oil cooler.

deliver cold oil to the hopper tank.

compensate for volumetric increases due to foaming of the oil.

direct oil through or around the oil cooler.

The pumping capacity of the scavenger pump in a dry sump aircraft engine's lubrication system

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is greater than the capacity of the oil supply pump.

is less than the capacity of the oil supply pump.

is usually equal to the capacity of the oil supply pump in order to maintain constant oiling conditions.

is greater than the capacity of the oil supply pump.

In which of the following situations will the oil cooler automatic bypass valve be open

the greatest amount?

Answer Choices

Engine oil above normal operating temperature.

Engine oil below normal operating temperature.

Engine stopped with no oil flowing after runup

Engine oil below normal operating temperature.

An engine lubrication system pressure relief valve is usually located between the

Answer Choices

oil cooler and the scavenger pump.

scavenger pump and the external oil system.

pump and the internal oil system.

pump and the internal oil system.

Low oil pressure can be detrimental to the internal engine components. However, high oil pressure

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should be limited to the engine manufacturer's recommendations.

has a negligible effect.

will not occur because of pressure losses around the bearings.

should be limited to the engine manufacturer's recommendations.

The valve assemblies of opposed reciprocating engines are lubricated by means of a

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gravity feed system.

splash and spray system.

pressure system.

pressure system.

What determines the minimum particle size which will be excluded or filtered by a CUNO (stacked disc, edge filtration) filter?

Answer Choices

The disc thickness.

The spacer thickness.

Both the number and thickness of the discs in the assembly.

The spacer thickness.

The engine oil temperature regulator is usually located between which of the following on a dry sump reciprocating engine?

Answer Choices

The engine oil supply pump and the internal lubrication system

The scavenger pump outlet and the oil storage tank.

The oil storage tank and the engine oil supply pump.

The scavenger pump outlet and the oil storage tank

Where are sludge chambers, when used in aircraft engine lubrication systems, usually located?

Answer Choices

In the crankshaft throws.

Adjacent to the scavenger pumps.

In the oil storage tank.

In the crankshaft throws.

The type of oil pumps most commonly used on turbine engines are classified

positive displacement.

variable displacement.

constant speed.

positive displacement.

The purpose of a dwell chamber in a turbine engine oil tank is to provide

a collection point for sediments.

for a pressurized oil supply to the oil pump inlet.

separation of entrained air from scavenged oil.

separation of entrained air from scavenged oil.

An oil tank having a capacity of 5 gallons must have an expansion space of

Answer Choices

2 quarts.

4 quarts.

5 quarts.

2 quarts.

Excessive oil is prevented from accumulating on the cylinder walls of a reciprocating engine by

the design shape of the piston skirt.

internal engine pressure bleeding past the ring grooves.

oil control rings on the pistons.

oil control rings on the pistons.

Compared to reciprocating engine oils, the types of oils used in turbine engines

are required to carry and disperse a higher level of combustion byproducts.

may permit a somewhat higher level of carbon formation in the engine.

have less tendency to produce lacquer or coke.

have less tendency to produce lacquer or coke.

In order to relieve excessive pump pressure in an engine's internal oil system, most engines are equipped with a

vent.

bypass valve.

relief valve.

relief valve.

As a general rule, the mixture setting on a reciprocating engine operating at or near takeoff power that provides the best

cooling is

Answer Choice

FULL RICH.

LEAN.

FULL LEAN.

FULL RICH.

The valve assemblies of opposed reciprocating engines are lubricated by means of a

Answer Choices

gravity feed system.

splash and spray system.

pressure system.

pressure system.

A drop in oil pressure may be caused by

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the temperature regulator sticking open.

the bypass valve sticking open.

foreign material under the relief valve.

foreign material under the relief valve.

As a general rule, a small amount of small fuzzy particles or gray metallic paste on a turbine engine magnetic chip detector

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is considered to be the result of normal wear.

indicates an imminent component failure.

indicates accelerated generalized wear.

is considered to be the result of normal wear.

How are the teeth of the gears in the accessory section of an engine normally lubricated?

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By splashed or sprayed oil.

By submerging the load-bearing portions in oil.

By surrounding the load-bearing portions with baffles or housings within which oil pressure can be maintained.

By splashed or sprayed oil.

As an aid to cold-weather starting, the

oil dilution system thins the oil with

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kerosene.

alcohol.

gasoline.

gasoline

Why is expansion space required in an engine oil supply tank?

Answer Choices

To eliminate oil foaming.

For oil enlargement and collection of foam.

For proper oil tank ventilation.

For oil enlargement and collection of foam.