Flying with fuel leak?

"G.R. Patterson III" wrote in message
I have proven empirically that keeping the tank switched to L or R helps.
Both
the local ramp by the fuel pumps and my tiedown are on slopes. If I fill
the
tanks to 1.5" below the filler tube (which is normally safe), park on my
tiedown, and leave the selector in the "off" position, the right tank (the
uphill one) will be down about 1/4 tank a week later. Leave the selector
on R,
and I'll still have full tanks. Similarly, if I leave the selector "off"
while
I'm fueling, frequently the downhill tank will overflow before I finish
paying
for the gas. I have developed the habit of leaving the selector on the
uphill
tank, but I cannot give you a good reason for doing that instead of the
downhill
one.

Thank you so much for the empirical results.

The newer maintenance manual (not my original one) references the
desirablity of leaving the fuel selector in "L" or "R" position when parked
to prevent tank to tank transfer. This implies that tank to tank transfer
can occur when the selector is either in the 'off' or 'both' position.

The bare spots are finally growing over in front of my hangar after 3 years
of the 'killing leaks'.

"Roger Long" wrote:
Am I just overly compulsive about maintenance or are these
people nuts?

Fairly common attitude, I've found. It's a big reason I stopped renting and
bought an airplane.

An FBO I used to rent from had a 172 with a primer that would squirt fuel
all over your hand every time you used it. Their idea of fixing it was to
tell everyone *not* to use it. Another place had a Warrior with an amp meter
that always read a high rate. Their advice: "Ignore it; it's always been
like that."
--
Dan
C172RG at BFM

"Dan Luke" c172rgATbellsouthDOTnet wrote in message ...

Their advice: "Ignore it; it's always been
like that."

Seems very reasonable. I have a CHT gauge in my Mooney that reads 20
degrees low (we tested the gauge to determine this). I'm not willing
to send Mooney $2000 of my money for a new gauge cluster (especially
since I have an EDM). So my advice to anyone flying my Mooney is to
just acknowledge that it reads low and use the EDM instead. In your
Archer, if the gauge ever read zero, it would get your attention. If
it read higher than the high it usually reads, it would get your
attention. Seems like the gauge is doing its job. We're not trying to
measure down to the milliamp here, those types of debugging are best
done on the ground with real equipment.

-Robert

"Roger Long" om wrote in message ...
I was looking over the web site of a flying club that posts the minutes of
their meetings. One item said that fuel was running out of the wing of
their 172 when the flaps were fully extended because the overflow drain was
broken. They asked that the tanks not be completely filled until this could
be fixed.

How much fuel? Some planes always leak fuel, the FAA has an approved
method to determine if a Mooney is airworthy by measuring how bad the
leak it. Even a great 172 in perfect share will leak fuel when sitting
at an angle with full tanks and the selctor on "both". Perhaps they
are waiting on a part? In anycase, I wouldn't ground a plane for a
small leak, if you did 1/2 the planes out there would be on the
ground.

-Robert

Yes, but here they were saying that the leak was due to a known defect that
would be fixed. Fuel pours out of the vent on our 172 all the time while we
are taxiing, that's what the vent is there for. If you knew that the pipe
that was intended to conduct overflow fuel from the tank to the ground was
sending it somewhere else in your Mooney or Maule, would you keep flying it?

--
Roger Long
Robert M. Gary wrote in message
m...
"Roger Long" om wrote
in message ...
I was looking over the web site of a flying club that posts the minutes
of
their meetings. One item said that fuel was running out of the wing of
their 172 when the flaps were fully extended because the overflow drain
was
broken. They asked that the tanks not be completely filled until this
could
be fixed.

How much fuel? Some planes always leak fuel, the FAA has an approved
method to determine if a Mooney is airworthy by measuring how bad the
leak it. Even a great 172 in perfect share will leak fuel when sitting
at an angle with full tanks and the selctor on "both". Perhaps they
are waiting on a part? In anycase, I wouldn't ground a plane for a
small leak, if you did 1/2 the planes out there would be on the
ground.

-Robert

Roger Long wrote:

If you knew that the pipe
that was intended to conduct overflow fuel from the tank to the ground was
sending it somewhere else in your Mooney or Maule, would you keep flying it?

If the vents to a tank become plugged on a Maule, the fuel will vent into the
wing and come out the flap area - at least, it will when the plane is on the
ground. Now. That does require that two conditions be met. 1) you have to
fill the tank to within 1.5" of the filler tube, and 2) something has to plug
the vent.

The vents are 1/8" tubing. There's a type of insect (probably a dirt dauber)
that thinks these are just perfect recepticles for eggs. When the larva gets
big enough, you have a blocked tube with no external signs.

I discovered this when I put too much fuel in one tank at Oneonta, NY. I flew
home. Cleared out the tube (I thought). The larva got big enough to completely
block the tube returning from Oshkosh that year. That resulted in an unscheduled
fuel stop and more work on the vents.

So, yes, I keep flying and fix it when possible. On the other hand, I don't have
electric flaps.

George Patterson
The British drink warm beer because they all own Lucas refrigerators.

In article ,
(Robert M. Gary) wrote:

How much fuel? Some planes always leak fuel, the FAA has an approved
method to determine if a Mooney is airworthy by measuring how bad the
leak it. Even a great 172 in perfect share will leak fuel when sitting
at an angle with full tanks and the selctor on "both". Perhaps they
are waiting on a part? In anycase, I wouldn't ground a plane for a
small leak, if you did 1/2 the planes out there would be on the
ground.

The original post said fuel was "leaking out of the wing" due to a broken fuel
vent. I understand that to mean that the fuel is venting into the wing then
running out. Put aside the mess is will make, suppose the nav light wiring
chafes and shorts? That happned to a Baron here several years ago, blew the
skin off the wing...luckily they were taxiing and not in flight.

If it were mine it would be fixed ASAP.

--
Dale L. Falk

There is nothing - absolutely nothing - half so much worth doing
as simply messing around with airplanes.

http://home.gci.net/~sncdfalk/flying.html

"Roger Long" om wrote in message ...
I was looking over the web site of a flying club that posts the minutes of
their meetings. One item said that fuel was running out of the wing of
their 172 when the flaps were fully extended because the overflow drain was
broken. They asked that the tanks not be completely filled until this could
be fixed.

Am I just overly compulsive about maintenance or are these people nuts?

BTW: Since I said something about Mooney, I feel I must say something
about Bonanzas too. Most of them will leak fuel out the filler cap
if filled to the top unless both the internal and external cap rings
are replaced regularly (and most are not).
-Robert

"Roger Long" om wrote in message ...
I was looking over the web site of a flying club that posts the minutes of
their meetings. One item said that fuel was running out of the wing of
their 172 when the flaps were fully extended because the overflow drain was
broken. They asked that the tanks not be completely filled until this could
be fixed.

Am I just overly compulsive about maintenance or are these people nuts?

I'm not going to say I've never flown an airplane with a fuel leak,
but it all depends on the situation. Without knowing the situation,
it's hard to judge.

Example, when I was towing banners. The company had 8 airplanes, and
all of 'em were 40-60 years old. Things break, and when you're using
planes to make money, sometimes you have to prioritize things.

On the first flight of a freshly restored plane (tow plane mind you,
so any luxury item has been removed, things like radios, windows,
doors, interior, ect.) everything was going well. Plane flew well,
engine was running ok, and everything seemed to work. Of course, we
only put 15 gallons in her for the one hour flight, so the tanks were
nowhere near full. The next day, when I showed up for work, I filled
the tanks and got ready to work.

Problem- fuel leak. The PA-12 has a fuel system simlar to a Cessna,
the left tank has a vented cap, and the right tank is vented to the
left, and there is a seperate shutoff valve for each tank. The cross
vent had fuel dripping right onto my shoulder. Heck with it, it'll
stop once I burn off a few gallons, and it's evaporating anyway and
without doors and windows, it's not like I'll have a problem with
fumes.

After 5 minutes it stopped and I was able to replace the fuel line at
the end of the day. It ammounted to MAYBE 4 or 5 oz. of gas lost, and
I was able to get the work done.

When it's your airplane that you're using for pleasure you can have
the luxury of downing the plane for a week to fix something as soon as
it breaks. But if there's no room in the shop until Thursday, well,
maybe you can fly it until then.

I'm not defending places that let the maintinace go, I've worked for
them before, but not for long. They don't do "maintinace," that's
what you do to keep something from breaking. They did damage control;
run it until it won't run no more then clean up the mess and fix it.
Is that what this club is doing?

It doesn't sound like it. It sounds like they want to fix it, but
don't want to inconvenience it's members for a minor squak while the
plane waits in the shop. I've flown out of places like that, you show
up to fly, but there's no airplanes available. The only one left is
grounded because of a bad attitude gyro. On a clear VFR day. But
it's not getting worked on, it's waiting in the shop because there's a
2 day backlog.

But not everyone has the luxury of flying something that looks like it
just came off the showromm floor. Now, if you're paying for a rental,
that's another story. If I were paying top dollar for something like
that, I'd want it to work properly too. But there are always two
sides to every story. Alot of times what's recorded in a club's
minutes is the distillation of a 30 or 40 minute debate into 3
sentence.


--
Mike O'Malley

Here's my perspective as maintenance officer of a different flying club:

Although we are all owners in common who have a say in the maintenance
policy, all of the members except myself are more removed from the issues
than the individual owner who talks directly to the shop. We are an
organization making an aircraft available to a group with a wide range of
understanding of aircraft systems and attention to what is going on. This
implies a higher standard than the guy who goes out and flies his personal
airplane.

Although we need a certain number of flying hours to afford to keep the club
going, every individual flight we make is optional.

I don't require that the aircraft be in perfect condition to be released for
flight but I do insist that it be legal. If something is inop and on the
required equipment list as part of the certification, it gets fixed before
the plane flies. If it can be placarded, it is and we fix it at the
earliest opportunity.

We maintain our aircraft very proactively. Failures have become rare.
Insisting on a standard of airworthiness and legality such that I wouldn't
worry about a ramp check on any flight has not cost us a single hour of
flying in the last year.

I can see where operators who do minimum maintenance and defer everything
possible get backed into a position where they have to constantly compromise
with the regulations. Since we started maintaining to a high standard,
usage is up, cash flow is better, and everyone is proud of our aircraft.
--
Roger Long
Mike O'Malley wrote in message
m...

I'm not going to say I've never flown an airplane with a fuel leak,
but it all depends on the situation. Without knowing the situation,
it's hard to judge.

Example, when I was towing banners. The company had 8 airplanes, and
all of 'em were 40-60 years old. Things break, and when you're using
planes to make money, sometimes you have to prioritize things.

On the first flight of a freshly restored plane (tow plane mind you,
so any luxury item has been removed, things like radios, windows,
doors, interior, ect.) everything was going well. Plane flew well,
engine was running ok, and everything seemed to work. Of course, we
only put 15 gallons in her for the one hour flight, so the tanks were
nowhere near full. The next day, when I showed up for work, I filled
the tanks and got ready to work.

Problem- fuel leak. The PA-12 has a fuel system simlar to a Cessna,
the left tank has a vented cap, and the right tank is vented to the
left, and there is a seperate shutoff valve for each tank. The cross
vent had fuel dripping right onto my shoulder. Heck with it, it'll
stop once I burn off a few gallons, and it's evaporating anyway and
without doors and windows, it's not like I'll have a problem with
fumes.

After 5 minutes it stopped and I was able to replace the fuel line at
the end of the day. It ammounted to MAYBE 4 or 5 oz. of gas lost, and
I was able to get the work done.

When it's your airplane that you're using for pleasure you can have
the luxury of downing the plane for a week to fix something as soon as
it breaks. But if there's no room in the shop until Thursday, well,
maybe you can fly it until then.

I'm not defending places that let the maintinace go, I've worked for
them before, but not for long. They don't do "maintinace," that's
what you do to keep something from breaking. They did damage control;
run it until it won't run no more then clean up the mess and fix it.
Is that what this club is doing?

It doesn't sound like it. It sounds like they want to fix it, but
don't want to inconvenience it's members for a minor squak while the
plane waits in the shop. I've flown out of places like that, you show
up to fly, but there's no airplanes available. The only one left is
grounded because of a bad attitude gyro. On a clear VFR day. But
it's not getting worked on, it's waiting in the shop because there's a
2 day backlog.

But not everyone has the luxury of flying something that looks like it
just came off the showromm floor. Now, if you're paying for a rental,
that's another story. If I were paying top dollar for something like
that, I'd want it to work properly too. But there are always two
sides to every story. Alot of times what's recorded in a club's
minutes is the distillation of a 30 or 40 minute debate into 3
sentence.


--
Mike O'Malley