Replacing fuel cut-off valve with non-a/c part???

"Matt Whiting" wrote in message
...
Kyle Boatright wrote:

"RST Engineering" wrote in message
...

You really don't understand, do you John? The process to approve this
part is NOT a simple 337. A 337 means you have approved data to make the
modification.

Oh, no, sir. You submit a request to the local FSDO inspector, who
transfers it to regional engineering, who passes it on to Oklahoma City,
who bucks it up the ladder to Washington DC for a policy decision, while
you wait, and wait, and wait for an answer.

This is a frikkin' low horsepower single engine airplane out of the
1930s. If the valve the person is suggesting that they use is available
at the local hardware store, it is far superior to ANYTHING that was
available in the middle of the last century.

Put the sumbitch on and keep your mouth shut.

Jim



You're a bad person.

But I totally agree. ;-)

The only way you get busted is if: A) The airplane crashes because the
valve failed and B) You open your mouth.

Actually, a crash for any reason is bad if it results in the uncovering of
the unapproved part.

Matt

Especially for the widow, and what little if anything will be left of the
estate once a lawyer finds out about the automotive valve.

It always amazes me how people insist on taking a chance on having a lawyer
walk away with your life's savings and assets just because they're too damn
lazy to track down the right part...

Juan

RST Engineering wrote:

If the valve the person is suggesting that they use is available at the
local hardware store, it is far superior to ANYTHING that was available in
the middle of the last century.

Having done a fair amount of plumbing repairs in the last fifteen years, I beg
to differ. Pay *close* attention to the country of manufacture. If the new valve
is made in the US, Canada, or just about any European country, Jim's statement
is absolutely correct. One made in Indonesia *may* be satisfactory. Having seen
the failure rate on the Chinese shutoff valves which I've put in, there's no way
I would install something made in Asia in my fuel system.

And make absolutely sure that it has the warning label to the effect that it
contains substances that are "known to the State of California" to cause birth
defects. That substance is lead, which is required in the manufacture of quality
brass valves.

George Patterson
The desire for safety stands against every great and noble enterprise.

"JDupre5762" wrote in message
...
I believe a ball type valve from the local hardware store
would do the trick,

Quite possibly true but not a legal repair.

A look at the FAR indicates replacing the valve is not a major thing
and a 337 is not require; however, the proposed valve is not certified
for use in an a/c.

Look deeper, deeper, deeper into those FARs. Per the FARs


Per WHICH FAR? I don't know how many Taylorcrafts have automotive stuff
in them. Hell, they were built that way. They have copper plumbing and
SAE 45 degree fittings and valves and on and on. The A&P who owned a
Taylorcraft used to say, when you were changing out a part, "equal to or
better." Now THAT's in the FAR's or somewhere in advisory circulars. I've
seen it.

I know a Cub with a fuel shutoff valve from Home Depot. It's been there,
installed by an A&P, for years. And you know what? It still works.


you cannot replace a
certificated part with common hardware store parts unless those parts meet
whatever standard applies. If you were to replace the fuel shut off valve
with
something not certificated for that aircraft you would need a Form 337 to
gain
approval.

A 337 doesn't get you approved; that's for major repairs and alterations.
You would need to go running to the FSDO for approval first.

I plan on talking with the local FSDO, but until then, can someone
provide any insight into what I'm going to have to do? Thanks, Mike

I plan on talking with the local FSDO

Then you will never be able to do it. Never. Once they know you had
plans to do it, you lose plausible deniability.

Look, here's the way it is. All alterations to the fuel system are
major. You have no approved data. You have an unapproved part. It
would take an STC or field approval to make it happen, and you won't
get one. You're stuck with either your obsolete, leaky, marginally
safe - but legal - valve, or you make the alteration yourself, by dark
of night, and don't tell anyone. And make sure you have the kind of IA
who doesn't notice such things.

Michael

It really gets down to time and money namely a lot of yours not the
government's so you can educate the FAA government bureaucrat on
modern technology and he can cover his ass in a lot of expensive paper
work..
It could easily cost you more than $50,000 and two years to get that
$5 valve approved by the time you ran enough tests at a CERTIFIED Lab
with certified calibrated equipment using an APPROVED test plan
that will have to be written. The FAA guy will then dream up more
tests so you will have to jump through more hoops. Have you never
heard of the Bob Hoover medical problem? Same problem here.

I once had a certified helicopter that had a drilled head pivot bolt
in the tail rotor bell crank that held the bell crank in place. The
bolt's nut was a standard ordinary non fixed to the airframe all metal
self locking nut per the parts manual also. The parts manual showed
that both the drilled and un-drilled AN-6 parts were both approved in
this location. The FAA dick head insisted that if the drilled head
bolt was installed it had to be safety wired to something. What the
hell good is keeping the bolt from turning going to help if the nut is
free to rotate? The A&P /IA showed the FAA dick head the CURRENT
version parts manual, acceptable, approved data.
So the Faa dick head insisted on calling the helicopter MFG. After a
couple of hours on the phone the end result was the parts manual is
correct as it stands per the aircraft MFG. If we had the correct
length AN6 un-drilled bolt we would have changed it but to get one
would take a day or more of lost revenue.
After more than 4 hours the problem got resolved at 4:59 PM when the
FAA guy said I guess that drilled head bolt's OK and went home.
Total cost to me over $200. Did this improve anything? I think not.
The real problem is the FAA inspectors do not want to be held
accountable for ANY judgment calls without a load of expensive paper
to cover their ass and they also like to show the "troops" who is the
boss.
John

On 28 Dec 2004 13:21:19 -0800, "Michael"
wrote:

I plan on talking with the local FSDO

Then you will never be able to do it. Never. Once they know you had
plans to do it, you lose plausible deniability.

Look, here's the way it is. All alterations to the fuel system are
major. You have no approved data. You have an unapproved part. It
would take an STC or field approval to make it happen, and you won't
get one. You're stuck with either your obsolete, leaky, marginally
safe - but legal - valve, or you make the alteration yourself, by dark
of night, and don't tell anyone. And make sure you have the kind of IA
who doesn't notice such things.

Michael

Geez y'all, with all the arguing, somebody could have found an approved part
from a certificated aircraft, gotten the conformity data, submitted a 337 with
details, drawings and instructions for continued airworthiness and most likely
have gotten a fuel cutoff valve that doesn't leak.


--
Dr. Nuketopia
Sorry, no e-Mail.
Spam forgeries have resulted in thousands of faked bounces to my address.