Oil is the lifeblood of your engine and because about half of all general aviation aircraft hold it behind quick drains you should know how those drains work. Aside from the utility and improved safety for the mechanic or pilot who drains the hot oil from their engine, these quick drains do come with some risk — if they are not used properly, they can pop open in flight and quickly drain the oil from your engine!
HOW THEY WORK: The fixtures are pressed in to open, pulled out to close and are intended to eliminate the mess that usually comes along with a regular oil change. An oil quick drain eliminates the task of removing the drain plug, along with the five to twelve quarts of oil that are held behind it.
Preflighting Your Quick Drain:
- If the engine is cool, TUG the connector in the closed (typically outward) direction, to assure that the drain valve is fully closed.
- While you are looking at the quick drain, check for drain tubing left connected to the quick drain.
- Always check the quick drain connector on your engine after an oil change.
Inside Information: Retractable aircraft are more at risk than non-retracts for trouble regarding item #2, above. Why: When the temperature outside drops (‘tis the season), flexible tubing becomes more rigid. As landing gear retracts, it can contact the stiff tube, causing the quick drain to open.
FOR RENTERS: If you don’t know the maintenance history of your aircraft, always look to assure that the quick drain is closed, and that no drain tube has been left attached. In any case, if the drain valve is questionable, or a drain hose is attached, do not fly the plane until the situation is corrected!
BOTTOM LINE: The results of opening an oil quick drain in flight are well documented and are all bad. There is a rapid loss of oil, which causes loss of oil pressure and engine seizure. If you’re *very* lucky, there is no fire –but don’t count on it. Instead, keep these tips in mind and practice your off-field landing skills with an engine that works.