I was going to seal the firewall with fuel tank sealant diluted with MEK (methyl-ethyl-ketone) solvent but when I mixed the fuel tank sealant with the hardener; (1/2 hour of hand-pumping a little plunger to mix the nasty stuff), it blew the tip of the applicator off and was already hardened into a rubber blob. That’s when I realized I was trying to use fuel tank sealant that expired 8 years ago! My bad. Plan “B” was to use high temperature RTV to seal all the possible places gases under pressure could pass from a leak in the engine exhaust into the cockpit. The pictures below show me sealing every bolt, pop rivet, reinforcing plate, metal tooling hole/space, and all the metal flanges & bend-holes in the F106 K-1 firewall recess plate. After the RTV dries, I will install the Firewall Shield material to completely seal the firewall and keep any excess heat (or a real fire) from penetrating the firewall.
