Teledyne TSIO-360-RB, Maintenance Manual

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7-4
7-4 OIL FILTER ELEMENT INSPECTION
Inspect oil filter element at each oil and filter change even if oil analysis is being used. Filter
element inspection may identify internal engine wear that will not be identified through oil
analysis.
New, rebuilt, overhauled engines or engines that have had cylinders replaced will generally
exhibit noticeable amounts of normal wear material at the first and second oil and filter
change. The amount of material present should significantly decrease between the first and
second oil and filter change if the engine and or cylinders have been properly operated
during the break-in period.
As with oil analysis, oil filter element inspection provides maintenance personnel with
additional information on the wear characteristics of a specific engine. Sudden, unexplained
increases in concentration of wear material in a filter element should alert maintenance
personnel to investigate the source and cause of the material.
Material Identification:
Ferrous - attracts to magnet.
Aluminum - will "sizz" or bubble when placed in a 50 % solution of muriatic acid.
Bronze or Copper - will turn bright green when placed in nitric acid.
Carbon - will disintegrate when rubbed between index finger and thumb.
Sand - will not disintegrate when rubbed between two hard surfaces and will scratch glass
when pressure is applied.
Nickel - will not be magnetically attracted but looks similar to ferrous material.
Tin - will not be attracted magnetically. It looks similar to nickel but is soft and malleable.
7-5 SPECTROGRAPHIC OIL ANALYSIS
Spectrographic oil analysis has become popular with the owners and operators of general
aviation piston powered aircraft. This process was developed more than 35 years ago by
the railroads as a method of identifying wear characteristics in large diesel engines.
Eventually oil analysis was adopted by the military and then by commercial and general
aviation.
Engines are designed and manufactured using various materials and alloys. The engine
lubrication system is designed to provide either pressure or splash oil to areas of the engine
subjected to frictional loading. During normal operation these areas undergo minute,
continuous wear; sub-micronscopic material is released from these contact surfaces and are
suspended in the lubricating oil. Spectrographic oil analysis identifies these materials and
their level of concentration in parts per million (PPM).
There are two accepted methods of performing oil analysis: atomic absorption and atomic
emissions.
Atomic absorption will identify suspended wear material that is five micron in size or smaller,
while atomic emissions will identify suspended wear material that is ten micron in size or
smaller. Since engine oil analysis is used as a tool to establish engine wear trends and
deviations from the established norm, either method is acceptable; however, it is important
to realize the oil analysis program must utilize the same laboratory for all sample analysis.
Comparing an oil analysis report from a separate laboratory will have little meaning if each
laboratory uses a different analysis method.