Lubrication Systems Flashcards
What is straight mineral oil?
It is the lubricating oil as obtained by fractional distillation of crude oil. It does not have any additives.
What is ashless dispersant (AD) oil?
A mineral lubricating oil containing additives that disperse the contaminants throughout the oil so they will not clump and clog oil passages. There are no ash-forming additives in AD oil.
What is synthetic oil?
A lubricating oil that is made by chemically changing the nature of an oil base to give it the needed characteristics. Synthetic oil is the primary oil for turbine engines.
Is automotive oil suitable for use in aircraft engines?
No, automotive and aviation oils are formulated for entirely different operating conditions.
What is meant by a multiviscosity oil?
It is a lubricating oil with a viscosity index improver that increases the viscosity of the oil when it is hot and decreases the viscosity when it is cold.
What are six functions of the oil in an aircraft engine?
a. Reduces friction.
b. Seals and cushions.
c. Removes heat.
d. Cleans inside the engine.
e. Protects against corrosion.
f. Performs hydraulic action.
Where can you find the grade of engine oil specified for a particular aircraft?
In the Aircraft Flight Manual or the Pilot’s Operating Handbook for the aircraft.
What components in a reciprocating-engine lubrication system must be inspected on a 100-hour or annual inspection?
The oil sump or tank, the oil strainer screen, the oil filter, the oil cooler and the temperature control valve, the oil pressure and temperature gages and any transmitters associated with them, and the entire engine for indication of oil leaks.
What two instruments show the condition of a reciprocating-engine lubrication system?
Oil pressure and oil temperature gages.
What must be done to an oil filter when it is removed from the engine?
It should be cut open and the pleated element examined to determine the type and amount of contaminant carried by the oil.
What is a spectrometric oil analysis program?
A program in which a sample of oil is taken from the engine at regular intervals and sent to a laboratory, where it is burned in an electric arc. The resulting light is analyzed for the wavelengths of the elements that are present in the oil sample. Traces of aluminum, copper, and iron in the oil indicate wear of the pistons or wrist pin plugs (aluminum), cylinder walls or piston rings (iron), main bearings or bushings (copper). A single sample is meaningless. There must be a series of samples taken at regular intervals to measure the change in the amounts of these metals.
What is the purpose of an air-oil separator, or deaerator, in a turbine engine oil tank?
In normal operation, the oil picks up a quantity of air and it is swirled as it enters the deaerator. The swirling action releases the air from the oil, and the air is used to pressurize the oil tank.
What type of oil quantity indicator is used in most aircraft engines?
A dipstick that measures the quantity of oil in the tank or sump.
When should the engine oil quantity be checked on a turbine engine?
As soon as practical after the engine is shut down.
Where is the oil temperature measured on a reciprocating engine?
Usually at the oil pressure screen before the oil goes into the engine passages.
