The special restrictor fitting that Aircraft Specialty supplies attaches onto the existing fuel return fitting on the firewall shelf. The restrictor fitting has a VERY tiny orifice drilled into it which accomplishes the same task as the restrictor inside the Van’s VA-216 fuel return hose. So the order of assembly is to first install the restrictor fitting with the TINY hole onto the existing fuel return fitting on the firewall shelf, then attach the fuel return hose (#5 in the second photo of the previous post) that comes from the aft fitting on the fuel marshal. In order to photograph the hole in the restrictor so the viewer can see the hole more clearly, the restrictor was taped onto a flashlight with red tape so light could be photographed coming through the hole.
The restrictor fitting was placed on the fuel return fitting on the firewall shelf and torqued to specs then the Teflon fuel return line was installed onto the restrictor fitting and connected to the aft port on the fuel marshal.
The Fuel the return hose (#5 in the second photo of the previous post) is attached onto the Aircraft Specialty provided fuel return restrictor fitting which is attached onto the fuel return fitting on the firewall shelf.
Connecting the fuel return line (#5 in the second photo of the previous post) onto the aft port on the fuel marshal. The other end of this hose runs to the fuel return fitting on the firewall shelf as seen in the previous photo.
The last remaining hose in the Aircraft Specialty fuel line kit connects to the last remaining port on the fuel marshal … this hose goes to the Kavlico fuel pressure sending unit on the firewall. The fuel pressure sending unit was prepared by installing a 90 degree fitting on the sending unit and mounting it onto a rubber grommet after the hole in the grommet was made larger per the plans.
The fuel pressure sender hose (#4 in the second photo of the previous post) connects between the remaining port on the fuel marshal and the Kavlico fuel pressure sending unit mounted on the firewall.
The remainder of the work session involved torqueing the fuel fittings, reviewing the wiring changes being made and making preparations to move the oil pressure sending unit from the engine to the firewall alongside the fuel pressure sending unit. Fittings needed to be installed and measurements taken for a custom oil line that Aircraft Specialty will be making for the DOG Aviation RV-12. Will post photos later once the hose is installed.