Exam (elaborations) LUBRICATION SYSTEM

1. What is meant by the viscosity of engine lubricating oil? correct answers The resistance of the oil to flow. 2. What is meant by a wet sump lubrication system? correct answers A lubrication system in which the oil is carried inside the engine itself. 3. What is meant by a dry sump lubrication system? correct answers A lubrication system in which the oil is carried in a tank that is not a part of the engine. 4. How is oil temperature controlled in an aircraft reciprocating engine? correct answers Hot oil is directed through the core of the oil cooler but cold oil is directed around the outside of the core so it will not be further cooled. 5. Is the oil temperature shown on the aircraft instrument panel the temperature of the oil entering the engine or of the oil leaving the engine? correct answers It is the temperature of the oil entering the engine. 6. What is the purpose of oil dilution in a reciprocating engine? correct answers When very cold weather is anticipated gasoline can be mixed with the lubricating oil before the engine is shut down. This reduces the viscosity of the oil and makes starting easier. When the engine is running the gasoline evaporates out of the oil. 7. What is the function of the hopper in the oil tanks used with some reciprocating engines? correct answers Hoppers are a part of the oil dilution system. Only the oil in the hopper is diluted. This speeds up dilution and requires less gasoline. 8. What happens to the gasoline that is used to dilute the oil in the crankcase of an aircraft reciprocating engine? correct answers When the engine is running and the oil is warm the gasoline evaporates out of it.