Trent's RV14 Build: 18-09: Miscellanea Installation (incl Fuel Senders)

Before the tanks could be tested, all the holes in the tank needed to be filled. These included the fuel strainer (fuel pickup), a bung to fill the fuel return link flange and the fuel drain into the fuel flange. All of these items were NPT (tapered pipe thread) so were installed using Loctite 565 on the threads to close the flow path around the screw helix. This stuff cures in a few hours in a non-oxygen environment (aka, between the threads).

You may notice that i have changed the CAV-110 fuel drains for the lock-open style seen above (personal preference).

Fuel Senders

The plans for the fuel senders call for discarding the rubber gasket which comes with the senders, and making a 'gasket' out of Proseal. You are supposed to apply a 1/16" thick bead of sealant, then progressively and evenly tighten the screws so that a 1/32" thick sealant layer is left.

You are also supposed to use a single lock washer (1/32" thick) between the flange of the fuel sender and the rib, in order to ensure the flange is properly grounded to the airframe.

So i figured why not just use a 1/32" lock washer on all the screws, then I should be able to tighten the flange down evenly until the lock washers are compressed and i should have my sealant bed.

Again, the threads of the screws provide a helical fuel flow path, so these had Loctite 565 applied to them.

I have also elected to have a ground return wire for the fuel senders under one of the screws as a more certain ground path back to my avionics.

Proseal 'bed' applied to the rib flange.

The fuel senders were both scuffed and cleaned so the proseal would stick

Here i have placed the washers on the screws - a much much better procedure is to use tweezers to stick all the washers to the proseal bed. You can then insert the screws covered in Loctite 565 into each hole and get them started.