Oil tank quick drain

[jrevens]

Has anyone installed a quick drain oil tank valve since the re-design of the bottom screen support plate? The new design has that concave plate in contact with the bottom of the tank where a quick drain would protrude when opened. Any thoughts about this or about the use of a quick drain in general? I've always had them on my Lycomings. What about putting a hole in the center of that plate? I'm wondering if the plate serves double duty in creating an area underneath for any small foreign particles, etc., to settle & stay out of the pick-up.

[Dorsal]

John,
I use a quick drain and love it, not sure about the generation of my tank.

[HighWing]

John,
I've always used a vacuum system. It is made from an old metal gas can, a length of tubing with a thin wall carbon Fiber tube on the end that will fit in the dipstick tube. A spring over the tube at the top prevents collapse when being used. Then a quick connect fitting that connects to my vacuum pump. Harbor Freight has a vacuum pump for about $70 from time to time. My pump is an oldie from Jewelry Making days.

The procedure is very tidy. I used to open the tank when empty and wipe it clean, but that is a thing of the past as I got in trouble once with that procedure. Then thinking the 912 is probably the only internal combustion engine on the face of the earth where that is possible, it became a step I felt had no practical value.

[jiott]

I always take the top off the tank & disassemble like Lowell used to do, and wipe out the inside because I use leaded fuel several times between oil changes when on x-countries. Curious Lowell what kind of trouble you had with this procedure? I emptied the oil with a Harbor Freight suction gun-quick and easy.

John I wouldn't put a hole in that bottom plate because that would allow oil to bypass the screen into the intake. The screen is very important to eliminate foam and air bubbles that are continuously being generated as crankcase pressure blows the sump oil back to the tank. Having been a hydraulics engineer in my past life, I can imagine that Rotax put some good engineering effort into developing that dry sump oil system to operate without excess foam, which is very bad if it gets into the pump and bearings.

[jrevens]

Thanks Lowell & Jim- I guess my only slight concern with pumping it out through the fill/dipstick hole is that there will be a small amount of dirty oil left below that bottom plate. You've both given me good info... thank you. I'm curious what problem you encountered also, Lowell. I don't much care for having to disassemble the tank at every oil change, but I guess it's a minor inconvenience in the grand scheme of things. Guess I'll probably forget about quick drains for now anyway.

[mr bill]

Why would the quick drain have to be located in the center, why not offset to one side ?

[JohnB]

I put the Curtis quick drain on mine (received engine Feb. 2014) and it has worked great for the first two oil changes. I didn't notice that it was hitting anything when opened

[jrevens]

I don't know when exactly the change was made, but the latest design has the plate basically touching the area of the bottom plug. At the very least, it would slow down the draining. My understanding is that Rotax discourages & does not recommend a quick drain there. It looks like the quick drain valve that I bought from Lockwood at OSH last year would probably slow that down also... you definitely would want to drain the oil while hot (you'd probably do it then anyway). I'm leaning towards changing the oil some other way.

[HighWing]

Thanks Lowell & Jim- I guess my only slight concern with pumping it out through the fill/dipstick hole is that there will be a small amount of dirty oil left below that bottom plate. You've both given me good info... thank you. I'm curious what problem you encountered also, Lowell. I don't much care for having to disassemble the tank at every oil change, but I guess it's a minor inconvenience in the grand scheme of things. Guess I'll probably forget about quick drains for now anyway.

John and Jim,
My reasoning is two fold.

First.
With any engine, there is always residual oil after draining the sump or tank. Every Lycoming or Contenintal, or auto conversion will have some residual oil - especially with conventional gear. Given our external plumbing and oil coolers, our amount is probably larger than most of those mentioned. Will an additional ounce or two make any real difference, or will removing the lead residue from that tank compensate for that left in the case or reduction drive. Most of us already change oil at relatively more frequent intervals than on most engines.

Second.
On the way to the 2007 Kitfox factory Fly-in, I had an oil pressure drop that resulted in the decision to make an emergency landing fairly near our home here in Cameron Park. The problem was a foreign something that was introduced into the tank during the "routine" wipe the tank oil change that had blocked the oil pick up tube. The result of that was an emergency landing that destroyed the airplane and broke a few bones. I am virtually positive if I hadn't decided to wipe the tank, that airplane would still be in my hangar with close to 2000 hours on it.

A few notes on Emergency landings.
Don't pay attention to the critics, they were not there - But there will be many.
Don't assume landing away from the river will be landing up hill.
Always, especially when approaching rough mountain terrain, land within three miles of first responders and next to a barn where the owner is out shoveling you know what with his cell phone in his pocket.
My wife has asked what would have happened if it had been 30 minutes later. We would have been over the Desolation Wilderness Area in the High Sierras.

[jiott]

Good points. I will be extra careful when I wipe my oil tank.