L3 Fuel gauge

[Aerco]

After lots of head scratching and a futile search for the correct kind of tubing (original was 3/8" cellulose acetate), I stumbled across the perfect solution while visiting Aircraft Spruce: They sell these fuel dipstick tubes; the kind calibrated for different aircraft; you stick the tube in and put your thumb over the end and you can read how much you have in there.

The tubing is obviously fuel resistant, and what's more has really thick walls and comes in many different lengths. I machined the ends down to where I could could cut 3/8" NPT threads on them. It cuts fairly well, after other types of tubing just cracked and splintered. I carefully removed the numbers with Solvent cleaner from Poly Fiber (MEK will ruin it and probably acetone too, so be careful), but left the division lines. The inside of the tube is very small so I sanded down the red platic "blob" a little to fit.

The cork was very brittle so decided to replace that and threw one of those modern plastic corks into some gasoline for several days. Nothing happened to it, so I used that after sanding it down to fit. Since it spends its life in alcohol, it ought to be Mogas resistant too! The $2 bottle of Zinfandel was a welcome break during all this.

At the lower end a 3/8" female/female coupling holds a Curtiss drain valve. All assembled with EZ-turn (messy stuff)and it seems to be tight and hasn't leaked in tests. It is far stronger and easier to read than the original, which snapped really easily when I tried to remove it.



Peter

Can't seem to add any pictures -"board attachment limit reached?"

[Paul Agaliotis]

Peter,
I have the glass tubing if you have the original aluminum gauge.
Paul