LUBRICATION SYSTEMS EXAM QUESTIONS AND WELL ELABORATED ANSWERS

LUBRICATION SYSTEMS EXAM QUESTIONS AND WELL ELABORATED ANSWERS List five functions of the oil in an engine lubrication system. - answers Cools, Cleans, seals and cushions, prevents corrosion, and reduce friction. The resistance of an oil to flow is known as its ________. - answers Viscosity. Oil that flows freely has a ____ viscosity. - answers Low. The oil used in reciprocating engines has a relatively _____ (high or low) viscosity. - answers High. The measure of the change in viscosity with a given change in temperature is know as the ______ ________. - answers Viscosity index. An engine lubricating oil whose viscosity changes very little for a given change in temperature has a _______ viscosity index. - answers High. The point at which liquid will begin to give off ignitable vapors is known as the _______ point. - answers Flash. Aviation 80 engine oil has the same viscosity as SAE ____ - answers 40 The use of straight mineral oil in aircraft reciprocating engines is associated with what conditions? - answers New/newly overhauled engines and older engines. The lubricating properties of straight mineral oil _______ (are/are not) as good as those of ashless dispersant oil. - answers Are not. Synthetic lubricating oils are ______ (multi or single) viscosity oils. - answers Multi If incompatible oil has been added to a turbine engine, it is often necessary to _____ and ______ the oil system before refilling with the proper oil. - answers Flush and refill. Turbine engine oils ______ (do or do not) use a standard identification system. - answers Do not. SAE numbers _____ (are or are not) used to identify turbine oils. - answers Are not. Two types of lubricating systems for reciprocating aircraft engines are _________ and ___________. - answers Wet sump and dry sump. The lubricating is distributed to the parts of a reciprocating engine by these three methods: - answers Pressure, Splash, and combination (spray). The main disadvantages of a wet-sump engine are: - answers Size is limited, cooling is less efficient, and temperature is higher. What two markings must be on the oil filler cap? - answers Oil, and the tank capacity. Oil tanks used on engines equipped with hydromatic propellers will feed the pressure pump from a stand-pipe, leaving a reserve of oil for _________ _________. - answers Propeller Feathering. A gear-type oil pump is a ______ (constant or variable) displacement pump. - answers Constant. Constant-displacement oil pumps ______ (do or do not) require a relief valve to control their output pressure. - answers Do. The two types of oil filter systems are: - answers Full flow, and bypass. In the ____ (full-flow or by-pass) filter system, only a portion of the oil is filtered each time it circulates. - answers By-pass. The most popular filter in common use for general aviation aircraft is the disposable ________ (surface of semi-depth) filter. - answers Semi-depth. The Cuno filter is an _____ (edge or depth) filtration type oil filter. - answers Edge. The _____ _______ (flow control or surge protection) valve determines which of the two possible paths the oil will take through a cooler. - answers Flow control. When the oil is cold, it flows _____ (through or around) the core of the oil cooler. - answers Around. ___ ________ is a system installed on some reciprocating engines to aid in cold weather starting by introducing fuel into the oil system prior to shutdown. - answers Oil Dilution. Oil pressure is measured at the _____ (inlet or outlet) of the engine driven oil pump. - answers Outlet. The 6 main contaminants found in used engine oil are: - answers Gasoline, moisture, acids, dirt, carbon, and metallic particles. Oil coolers are normally removed and thoroughly cleaned and inspected at ____ _______ (what event) - answers Engine Overhaul. The oil pressure on engines used an adjustable oil pressure relief may be increased by turning the adjustment screw ___________ (clockwise or counter-clockwise) - answers Clockwise. Oil consumption in turbine engines is ____ (lower or higher) than that in reciprocating engines. - answers Lower. Most turbine engines use ______ (what type) lubricating oil. - answers Synthetic. Most gas turbine engines for aircraft use a _____ (wet or dry) sump oil system. - answers Dry. Turbine engine oil tanks must have an expansion space of ___ % or 0.5 gallon, whichever is greater. - answers 10% Two methods of determining the amount of oil in a dry-sump system oil tank are: - answers Sight gauge and dip stick. Three types of oil pumps used with a turbine engines are: - answers Vane, Gear, and Gerotor. The gerotor pump is considered a ______ (positive or variable) displacement pump. - answers Positive. One micron = ________ inch - answers 0.000039. Three types of main system oil filters used with turbine engines are: - answers Disposable paper, cleanable screen, screen and spacer. Fine mesh screens called ____ _____ filters strain the oil just before it is sprayed onto the bearing surfaces of a turbine engine. - answers Last chance. Check valves in the oil supply lines prevent accumulations of oil in the _________ ________ (what area) of the engine while the engine is not operating. - answers Accessory gearbox. The cockpit oil pressure gauge measures the pressure ______ (upstream or downstream) of the main oil filter. - answers Downstream. The location of the oil temperature sensor in a turbine engine ____ (does or does not) make a significant difference in readings. - answers Does not. If the oil cooler is located in the pressure subsystem of a gas turbine engine, the engine uses a ___ (hot or cold) tank lubrication system. - answers Hot. Two types of oil coolers used with aircraft gas turbine engines are: - answers Air and Fuel. If turbine oil is observed to be dark brown or blackish with little or no contaminants present, it is probably caused by a chemical reaction to _____. - answers Heat. Oil pressure adjustments on turbine engin