Fuel gauge ideas

[Flyin Farmer]

My model III project is coming together however I have hit a small roadblock. I had planed on using a standard Kitfox fuel level tube for a gauge which I had purchased ,but when I started to install it I found my fiberglass wing tank has no reinforced points for the threaded fittings to go into just a fuel outlet and a breather outlet. I called Kitfox and they said I must have a really old tank and did not recommend drilling into the thin tank wall and therefore I need some means of getting a fuel gauge that will work ,looking for ideas. Thanks

[efwd]

Would you not be able to lay up addtl layers of fiberglass to make the wall as thick as you want and drill through it then?
Eddie

[Av8r_Sed]

Mine don't use threaded fittings. I drilled and installed rubber bushings and push-in 90 degree fuel fittings. I believe many are done this way. No leaks in 5 years.

Note: Tubing clamps added later

[Flyin Farmer]

Thank you for the help the rubber grommet and fitting looks like a winner,where did you get them and what size are they? Your placards look great also

[Dusty]

It looks like you have a wire inside the sight tube.Does this make it easier to see the fuel level?

[Dave S]

Dusty,

I believe the reason for the wire is to maintain the correct shape of the tygon tubing - a bow in the tygon would affect the accuracy of the sight gauge.

Having the updated version, I can tell you the wire does not help with seeing the fuel level.

[Av8r_Sed]

The wire doesn't help nor hurt the ability to see the fuel level. The stripes on the placard help a lot due to the diffraction of the fuel in the tube. The stripes appear vertical through the fuel.

[Rocketman]

I have the sight tubes on my Series V. They were installed 8 years ago and have worked fine. One caution though. When they start to discolor, check them especially carefully to see if they've also hardened. My aircraft is hangared and I thought the discoloration was normal, but during the annual condition inspection, when I touched them, they were hard and actually cracked and crumbled. My recommendation: replace them at the first sign of discoloration and save yourself a leak issue (replacement is easy and inexpensive.)

[Av8r_Sed]

I replace mine every year. It doesn't take long and all tubing like that seems to degrade quickly when it sees auto gas, ethanol free or not.

[efwd]

Mine has never met gasoline and they are already discoloring.
Guess I’ll be replacing it before adding fuel.