Next you will drop the washer
into the fuel tank (with the beveled side facing up to mate with
the fuel fitting bevel) and allow it to slide down the string
to the bottom of the fuel tank. You can reach your finger up into
the tank outlet and insure that the washer has room to fit flat
against the bottom of the inside of the tank. Too large of a washer
OD may not fit.
You do the same for the fuel
outlet fitting.
In the photo below the fuel tank
fitting end has been slid down the string, through the washer,
and out of the bottom of the fuel tank.
Now you should tie off the upper
end of the string to prevent it from falling into the fuel tank
as you are working on the bottom end. The string will keep the
fitting and washer captive until you have them secured in place.
Slide the rubber grommet up the string and into place around the
fuel fitting threads and inside of the tank hole. You will need
to hold onto the outlet fitting threads to keep the fitting from
going back into the tank. The grommet will hit the new washer
inside of the tank.
Next slide the bottom washer
and nut up the string and into place on the threads of the fuel
tank outlet fitting. Tighten the nut and then reattach the fuel
lines on each tank when you are finished installing hte fittings.
Your fuel tank outlet fittings
will not be able to fall out of the fuel tanks now while you are
flying so you now have a much safer helicopter.