Left fuel tank

Tonight I dropped the left fuel tank, and then found all the parts I needed to install the fuel senders and run the tank test. It took a while to find everything, despite my fairly organized boxes of parts.

I actually started during the day, Jen gave me a hand to lift the right wing out of the way so I could unscrew all the screws on the top of the left wing. Then later in the evening I was able to remove the bolts holding the baffles to the spar and carefully remove the tank.

Moving the right wing out of the way so I can work on the top side of the left wing
Unscrewing fuel tank screws from the left wing
Tank removed and on the work benches, now back inside the garage

With the tank out of way, I was able to get a look at some of the countersinking on the spar. Not that great to be honest. Most of the holes have countersinks down to a knife edge, and the edges are not symmetrical. There are signs of chatter during the countersinking process on some of the smaller holes for the access plates, and some of the holes are misshapen.

Signs of poor quality countersinking on the QB spar

Next up I located the fuel senders, the floats, the tank drain plugs, the fuel return plug, and screws for the sender.

Then I took a few minutes to test the fuel senders. These should have a range of 30 to 250 ohms when the arm is moved. Both the left and right senders measured correctly, the right was exactly 30 to 250, and the left was 27 to 275, which is close enough.

Testing the fuel senders. This is the left wing sender with an almost full deflection

Now I need to find some product to remove the thin layer of old proseal on the senders, from when I installed them on the last wing. Once they are cleaned up I’ll install them and can start the tank test. I’m planning to do one tank at a time, just to save working space.