Can not find wing tank drain holes

[Woodymuler]

I picked up a “not quite finished” KF5 Safari in September. I’m the 5th owner of this very drawn out build. So, Over the past several months, starting at the tail and working forward, I have gone through every nut, bolt and cotter pin, referencing the build manual as I go.

I noted the absence of wing tank drains when I inspected the wings. Upon referencing the build manual I learned these are not installed/fabric cut until after finish paint, so I moved on.

I am now going Through the fuel system and went back to install/cut the fabric for the quick drains but I can’t find a hole. I can feel the round bulge on the bottom of the tank through the fabric but no hole or plug, it feels smooth and solid.

Am I missing something here?

Any advice would be greatly appreciated,
Thanks,
Todd

[PapuaPilot]

There might be a plug in the drain hole that is flush or a piece of tape over it. Did you get any pictures from the previous builders?

I got my kit secondhand, but mine had threaded holes.

[Kahle76]

I just installed my drains on a new set of wing tanks that were made with the ethanol resistant resin from Kitfox. They were predrilled and tapped at the factory. During the fabric covering I covered the drain hole with tape to seal the hole. To find the drain hole I massaged the bump through the fabric until I could see the outline on the hole and then I used a sharp punch to push a hole through the fabric and the tape that covers the drain holes. Using a soldering iron, I enlarged the hole to the proper size and installed the drain with sealant.

[Woodymuler]

Thanks for your responses,
I have some photos, but none that show that portion of the wing build and very limited info on the fabric portion of the build. Owner number 4 (who I purchased from) had it for a year and never took it out of the enclosed trailer it came in, he did not work on it. Owner number 3, has been very helpful but his portion of the build was the panel and firewall forward (factory new 912ULS). #3 told me that he had put fuel in both tanks, run the engine and taxied it few times. He had no idea about the drains and had no fuel leaks.

So, it either has some really good tape over those holes, really smooth plugs in the holes or worst case scenario, no holes at all. What are the chances that these old tanks were sent without drain holes?

I guess I will center my blade on the bulge and start cutting an expanding hole until I hopefully find something.

[airlina]

Don't know if you could manuver it to the exact spot, but if you could get a boroscope, and put it thru the fuel tank filler hole or the fuel line outlet hole, and find the drain from above you could see whats going on and whether its got a plug or tape in the drain hole. I built a Series 5 Outback circa 1999 Kit and have drains in the tanks and I doubt Skystar sold tanks without drains . Bruce N199CL

[n85ae]

Just a thought -

There was a thread I think at one point about simply plugging them, since they don't tend to work
very well, and simply use the header as the sampling location since it is the true low point in the system.

I have been thinking about that as well, since I have never had anything in the tank drains except clean
fuel in the 16-17 years I have flown my plane.

I think in the tail dragger they don't trap anything in the tank low points to speak of.

Jeff

[efwd]

I did the slosh in the beginning until I didn't find any more particulate matter. 150 hours later, I still find granules of fiberglass in my tail dragger wing drains.