All modern aircraft oil drain valves are "Lock Open" style. This means that they cannot accidently get pushed open and remain open. Most twist to lock open.
Valve is made from anodized aluminum with stainless steel components. They are double sealed to prevent leakage. Valves can be rebuilt.
Be sure to check for clearance before installation. The flush valve is available for limited clearance applications.
The Safair flush valve is the perfect choice for a close clearance engine such as on the Piper Arrow. These low profile oil drain valves are designed to clear retractable landing gears and other restrictions. This valve is very durable and can be rebuilt.
To open valve, merely screw on the opener adapter. You can partially open the valve for just a sample or continue screwing to fully open the valve. The valve is made from 360 brass and 302 stainless steel.
For mechanics, you might want to keep just the opener adapter in your toolbox in case the aircraft owner forgets to leave the oil drain opener with the aircraft.
--Note on aluminum drain valves--
Tapered pipe threads made from aluminum and screwed into an aluminum sump may be difficult to remove. It is desirable that the male threads be made of a different material. An antiseize compound may be used. Tapered pipe threads tighten against one another and become highly stressed. Due to this high stress and peculiar stress-strain characteristics of aluminum alloy, threads may deform permanently, causing sufficient misalignment to make it difficult to disassemble.
