since 1940

Carbon particles in aircraft oil filter or screen

1. Lots of hard carbon particles in the filter or screen are caused by high temperature oxidation of oil.

In severe cases there may be enough to clog the oil screen. Engines with piston oil squirts (usually factory turbocharged engines) will generate more of these particles from the oil hitting the hot underside of the piston. Check engine compression. If combustion gas leaks past the ring belt it elevates piston temperatures and oil oxidizes on the piston. If compression is good then suspect that combustion gas is blowing past the exhaust guide.

Remove the rocker cover and look at the exhaust valve springs. If combustion gas is passing through the guide then the exhaust springs will be black with fried oil deposits. 

Grab hold of the exhaust spring and move back and forth while observing the valve stem. If the valve stem wobbles back and forth more than a few thousandths of an inch then clearance between the stem and guide (or guide and guide boss) is excessive. Aircraft oil filters (we recommend the Champion oil filter) can give you a picture of the amount of thermal stress the oil was subjected to. 

 

Oil Filter Inspection Information

If you're a pilot, you're supposed to tell your gunner or crew when to bail out --not ask them. Parachute Sense US NAVY 1944

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Disclaimer: sacskyranch.com contains abundant information relating to aircraft maintenance. The information provided  is not intended to supercede or supplement the F.A.A. approved  maintenance and/or operator’s manuals. Those F.A.A. approved manuals must be utilized when performing maintenance and/or operating aircraft.