To cushion the bottom of the tank I got some 1/8″ thick neoprene. The best deal I found was sold as “tool box drawer liner.” I cut it so it is wider than the bottom so it wrapped up the sides a little then notched out the inboard rear edge to match the plywood.
The tank needed two holes, one for the drain and one for the fuel level sensor. I first drilled a small pilot hole then used a 1/2″ forsner bit. Never use a regular twist drill bit for this step, you will end up with a triangular shaped hole instead of perfectly round and the bushing won’t seal.
Then installed the rubber bushing.
At this point I realized this particular tank is too deformed to install the fuel level sensor because the top and bottom are curved inward so there is not enough clearance for the sensor.
Knowing these tanks do expand the first time they are filled with gasoline I had to stop the installation and fill this tank with gas and hope that resolves the problem. After a few days the tank was still deformed, so I sealed the tank and put a few psi of air pressure in it. The following day I removed the air pressure and let it sit with gasoline in it. After a few more days the tank is back to its normal shape and has held that shape for over a week.
Now I can install the fuel level sensor. I made sure that the sensor was about 1/4″ above the bottom of the tank and pressed it into the bushing.
I was concerned that the polycarbonate cover might bump the calibration switch on the sender so I cut a ring of plywood to protect the switch. I used some silicone to hold the ring in place.
The drain hole in the bottom of the tank was drilled and fittings installed.
Now the tank was installed into the wing. To hold it in place I purchased some tie down straps. They were way too long so I cut them shorter and heat welded the end so it does not fray. I routed then under the plywood and diagonal supports then over the top of the tanks.
The fuel line was routed from the elbow to a tee. Then to the drain and quick disconnect. This was not an easy task to accomplish without kinking the lines. It would have been easier if the quick disconnect was moved an inch or two forward but that would have made the quick disconnect higher which is undesired and more likely to get bumped by my elbows when sitting in the cockpit. Maybe cutting one barb off of the tee would help too.
After installing the cover panel I’m amazed at how well it looks.
Not much remains on the wings now. Grease aileron bearings, safety wire aileron bracket bolts, install wing tips and I need to get the rest of the wing polished so it shines like the tank cover and ailerons.