A little pesky fuel leak can be aggravating.

Especially when you’ve already had it “fixed” in the past, but it’s still leaking.  That was the case recently on an airplane that arrived at Classic Aviation for a fuel leak repair.

It turns out the inboard fuel quantity probe in this aircraft is about six feet long, and the wing must be removed from the aircraft in order to remove the probe.  The probe threads are sealed with a special sealant, and in this case, fuel was leaking past the threads.

So… we had to bite the bullet and remove the wing.

With the wing removed, it was simple to access the fuel tank at the inboard end.  This nylon rope worked well to dislodge the fuel tank assembly from its position in the wing, so it could be slid out of the wing cavity.  The leak was at the bottom left hole in the inboard end of this fuel tank, where the fuel quantity probe screws into the tank.  The tank assembly had to be removed from the wing because when the probe is reinstalled, it must be inserted into a teflon bushing, and this is nearly impossible unless you can reach inside the tank at the outboard end… and the only way to do this is to remove the whole assembly from the wing.

Since it was a rare opportunity, I had to take a picture of the inside of the DA-40 wing, where the fuel tank lives.

You can hear all about the process of fixing this fuel leak, and some lessons I learned, in today’s episode of the Airplane Owner Maintenance Podcast.

And… if you have a Diamond Aircraft (or any other general aviation aircraft, and you need some reliable maintenance, give us a call at Classic Aviation, LLC.

Yev Bondarev, Manager  540-234-0226

classicaviationshd@gmail.com