Fuel tank systems
Hours: 6.9 | Posted in Fuel TanksWith a syringe of fresh sealant in hand, I went through the left tank and encapsulated all the rivet heads, touching up any other spots that looked even slightly questionable.
Installed the snap bushings and ran vent line in both tanks, as well as installing the vent line fittings on the inboard end ribs. Easy enough. I did have to adjust the vent line clips at the fuel cap flange, making them slightly larger in diameter to accept the vent tube without binding.
Also attacked the tank access plates – deburred, attached nutplates for the fuel sender, installed the fuel line fitting, fuel pickup, anti-rotation bracket, and fuel sender, and prosealed over everything (as well as the vent line fittings in the tanks). The fitting of the fuel line fitting and pickup was an iterative process, as I put the plate on the tanks repeatedly to ensure that the end of the pickup was positioned as near the bottom of the tank as possible, yet reliably not rubbing on the tank skin. The plans designate drilling the rivet holes for the anti-rotation brackets to #30, which allowed me to fix the misalignment of the holes I would otherwise have had, as the fuel fitting didn’t end up directly centered between those two rivet holes, in order to put the pickup where I wanted it.
I also used AD1097AD4-5 rivets (flush “oops” rivets) on the anti-rotation bracket, rather than the specified AD470AD4-5′s (universal head), as there was simply no way any of my rivet sets would get in there with the fuel pickup installed (the nut gets in the way), and you can’t install the bracket before you install the nut, as its whole point is to keep the nut in place. So I used the oops rivets (this isn’t a structural point), and back-riveted them. Even then, the angle wasn’t perfect, so a couple of the rivets aren’t perfect, but I don’t see it being a big deal.
Nearly ready to put the baffles on these tanks…need to find a flaring tool to make the vent line flares, and have a second pair of eyes take a look inside first.