Term
| A reciprocating engine is found to have excessive oil consumption without evidence of any oil leaks, what is the likely cause |
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Definition
piston rings are worn or broken
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|
Term
| what are the functions of lubricating oil in reciprocating engines |
|
Definition
| reduce friction between moving parts and remove heat |
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Term
| name 2 important characteristics of aircraft engine oil |
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Definition
light enough to circulate freely and
heavy enough to provide the proper oil film at engine operating temp. |
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Term
| what could happen to an oil that is too low in viscosity at normal engine operating temp. |
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Definition
| oil film between moving parts is easily broken, resulting in premature wear |
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Term
| what are some of the factors that must be considered by an engine manufacturer in determining the proper grade of oil for a particular engine |
|
Definition
| the operating load, temp. and rotational speed |
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|
Term
| why do aircraft reciprocating engines use a relatively high viscosity oil |
|
Definition
| they have large operating clearances, operate at high temps and pressures |
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|
Term
| name some oil contaminants |
|
Definition
| metal particles, dirt, carbon, moisture and acids |
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|
Term
| what is a possible indication of low oil pressure together with high oil temp. |
|
Definition
| low or inadequate oil supply |
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|
Term
| in ashless dispersant oils, what function does the dispersant perform |
|
Definition
| causes sludge-forming materials to repel each other and remain in suspension until they can be trapped by the oil filter and drained |
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Term
| why do oil reservoirs have expansion space |
|
Definition
| provide for oil foaming, thermal expansion, and air in the return oil |
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|
Term
| what could cause oil foaming |
|
Definition
diluted oil
contaminated oil
and oil level being too high |
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|
Term
| what controls oil pressure in a gear-type oil pressure pump |
|
Definition
| oil pressure relief valve |
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|
Term
| what function does an oil cooler bypass valve perform |
|
Definition
| directs oil through or around the cooler in order to maintain operating oil temps. |
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|
Term
| what could be a possible indication if the oil cooler passage becomes obstructed |
|
Definition
|
|
Term
| where is the oil temp. bulb usually located |
|
Definition
|
|
Term
| what does the presence of metal particles in an engine oil filter indicate |
|
Definition
| abnormal wear and possible engine internal failure |
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|
Term
| what should be done if metal particles are found in an engine oil filter |
|
Definition
| follow engine manufacturer's maintenance instruction |
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|
Term
| where is the most critical point of lubrication in a gas turbine engine |
|
Definition
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|
Term
| what type of oil is used in a turbine engine oil system |
|
Definition
|
|
Term
| name 2 types of turbine engine oils coolers |
|
Definition
| air cooled and fuel cooled |
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