prkaye

Well Known Member
This is embarassing - I can't beleive I never noticed this before, but there are actually two oil drain plugs at the bottom of my oil sump. I've only ever drained oil from one (the one I knew about). I assume the second one is just there for convenience (i.e. one may be more accessible than the other?)
 
Correct! The additional drain plugs are because often one of them is blocked by something. For normal oil change, draining from one plug is sufficient.
 
Do we trust oil quick-drain plugs here? I have always hesitated for fear that a quick-drain could open in-flight with catastrophic results. But it would make oil changes a bit quicker and easier.
 
The one Van's sells is going on mine next oil change. If you see how they open and close I think your mind would be at ease. You definitely have to push up on them a fair bit, against a spring, and then turn to lock in order for oil to come out. Put it on whichever of your two drains is nearest the low point of the sump in whatever attitude your plane normally sits for oil changes.
 
The second plug comes in handy. If you instal an inverted oil system you will need both holes. The quick drain plug works well. I would not be afraid of it leaking. If you have a choice drain the oil from the hole that is lowest in order to drain the most oil from the sump.