tiggerinmk

The guys over here are big on in-flight defueling: The second clunk line is hooked up to a fuel line mounted on a pod with a small funnel on the end. The funnel end must be away from the propeller (for obvious reasons).

The defueller plane carries a small vacuum cleaner descended from those used to clean computer keyboards. A defueller probe extends from the rear of the defueller plane. The idea is to suck the fuel out of the plane in flight...

tiggerinmk

For more conventional defueling I bent the third tube to the bottom of the tank and attached a small piece of tubing. Sucks it dry with no problems....

Cactus.

My Feedback: (1)

lol thought as much

stuk_at_work

My Feedback: (111)

I also use (2) bent tubes. One bent up for the pressure line, the other bent down for fueling. I also put a length of fuel tubing over the ends of both lines, just in the off chance enough "tapping" will wear a hole throught the tank. The one for the vent will be much longer, and follow the top of the tank for a 1/2" or so. The "fill" line will have the fuel tubing "just" touch the bottom of the tank and will be cut at at a 45 degree angle so that it cannot "close up".

BTW, you have to have both pointing in the same direction to install the stopper (at least in every tank I've put together) and rotate one of them 180 degrees after the stopper is in place.

Bob101

I bend the vent line up at 45 degrees. Put a clunk on the engine line. And the fill/vent line I bend it down about 30 degrees and leave about 1/2" from the bottom of the tank - then I slip on a short piece of fuel tubing that's cut on a 45 on the end. If you have a clear enough tank when you hold it up to the light you can turn it till it sits right on the bottom and its far enough forward to not interfere with the clunk.

I've thought about using a 2nd clunk but I'm just lazy and use the clunk that comes with the tank usually.

Shubova

My Feedback: (9)

2 Klunk/Pump Setup.
Has anyone heard of this? An old timer showed this to me but I haven’t tried it yet to see if it really works. He said he read it in a RC magazine and uses it on all he planes.
It’s easier to understand if drawn out on paper so here it goes, stay with me.
Set up tank vent line as usual. Take the tubing that connects to the muffler and plug/cap it off.
The next line is set up like a standard fuel line with klunk at the end. Connect the end of this tube to the muffler then cut the tube at a convenient location and insert a check valve between the muffler and tank. I think the idea is that the check valve (engine running) allows air pressure from the muffler into the tank. (Check valve only lets fuel run one way.)
Last, set up another fuel line with klunk at end. Add a fueling valve to this line and connect to the carburetor.
I was told this is like a pump with continuous fuel flow.
Again I am asking if anyone has heard of this. I have not tried it nor am I sure the set up is exactly correct. And no I am not nuts!
Sensible feed back will be appreciated.
Bern
[8D]