Game Composites GB1 GameBird, Maintenance Manual

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Maintenance Manual GB1 GameBird
Page date: April 24, 2020
79-5
Christen Inverted Oil System
Type: Christen 802 Gravity Valve
Christen 803 Oil Separator
Manufacturer: Aviat Aircraft, Inc.
672 S. Washington Afton, WY 83110, USA
www.aviataircraft.com
The parts are supplied with the engine by the engine manufacturer Lycoming.
Spare parts can be obtained via Game Composites, Lycoming or Aviat.
The units do not require regular maintenance. If defective, the units must be replaced.
System Description
The Christen inverted oil system is
gravity operated and works for all flight
attitudes.
During normal flight, the weighted ball
valve at the top of the Christen 803 Oil
Separator is open, allowing blow-by
gases from the engine crankcase to be
vented from the breather port to the top
of the Oil Separator, and out through the
overboard breather line. The top ball
valve of the Christen 802 Gravity Valve is
closed, and the bottom valve is open.
This permits oil to flow from the sump
out to the oil pump and engine
lubrication points.
When the aircraft is inverted or during
negative-g maneuvers, engine oil falls to
the top of the engine crankcase. The
weighted ball valve in the Oil Separator
closes, preventing overboard loss of oil
through the top of the Oil Separator.
Blow-by gases from the engine crankcase
are vented from the sump to the bottom
of the Oil Separator and through the
overboard breather line. The top ball
valve of the Gravity Valve is open, and
the bottom valve is closed, allowing oil to flow out from the breather port to the Gravity Valve, through the
sump fitting to the oil pump and engine lubrication points. Oil which fails to return to the sump during
transition between normal and inverted flight drains into the Oil Separator. This oil then returns to the sump
from the bottom of the Oil Separator during periods of normal flight, therefore the oil loss is reduced to a
minimum.