>I fly a 1978 Sundowner and it continues to have a severe smell of fuel in
>the cabin when opening up the doors after sitting a while. I have seen a
>quarter inch of fuel disappear from the left tank over a weeks time, but
>never have seen any fuel leaking from the plane. Mechanic said he dosn't
>smell the fuel, but other people do. He has spent several days looking for
>a leak and has uncovered nothing. Any ideas?

Let's see. Assuming that they made the fuel lines on the date of
production and not a year or two earlier letting them sit on the shelf, as
is quite common, your flex lines are 27 years old. The fuel lines run from
near the rear seat passenger's outboard foot on each side to the firewall,
probably 8 feet of line on each side that is VERY difficult to inspect
under the floor, and then there is the fuel selector and the line running
to the firewall. Some models had rubber hose and worm drive hose clamps
attaching the fuel lines to the fuel valve (never cared for that), and they
are notorious for weeping.

I've seen more than a few flex lines start weeping long before 27 years.

A pinhole in a hard line can weep fuel and still work normally for
flight. Its all on the suction side and under hydrostatic pressure from
the fuel in the tank, so it won't leak when the boost pump is on.

Antique seals in the fuel selector can also be an issue.

Pretty much You'll need to start by taking the seats out and pulling up the
carpet and floor boards to inspect for problems in the lines. The access
panels on the R&L rear kick panels under the door have got to come off to
see the fuel line where it enters the tank. I've seen them need a 1/16th
turn to snug the fitting and stop a slow weep.

This is all work that you can do without an A&P to sign off or supervise.

Next a flashlight and a mirror are needed, so you can examine the fuel
lines in the floor.

Bob Steward, A&P IA
Birmingham, AL

------------------------ Yahoo! Groups Sponsor --------------------~-->
Give the gift of life to a sick child.
Support St. Jude Children's Research Hospital's 'Thanks & Giving.'

Join BAC today and be a part of the ONLY Type Club for the Musketeer series!


Yahoo! Groups Links

<*> To visit your group on the web, go to:

<*> To unsubscribe from this group, send an email to:

<*> Your use of Yahoo! Groups is subject to: