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

Back in December I posed a question about replacing the fuel cut-off
valve in my 47 Tcraft with parts from HDepot. There followed heated
discussion. The outcome was we repaired the valve and re-installed it.
I don't have a lot of confidence that this will last 10 years, so the
issue is still open although on the far back burner.

In the meantime I acquired plans for replacing that valve with parts
from the local NAPA dealer. The plans make the following
statement:"Since automotive fittings were originally used on the
Taylorcraft there shold be no problem, just be sure your A&P checks
your work and signs it off".

Is the quote from someone talking off the top of their head or if not,
under what authority can that statement be made? - Mike

Might be able to do it if it is an exact duplicate and you have the
FAA-approved paper trail to prove it - not likely. Even though it may
look exactly the same, there are probably substantial differences you
can't see.

Want to make your own part see -
http://www.faa.gov/avr/afs/news/arch...2002/Parts.htm

If I were you I'd find a PMA replacement. That would be the legal and
cheapest option. Your mechanic can install a different PMA part as an
alteration with a 337 if you can't find the right one.

Just because you may find some A&P that will install something doesn't
make it anything other than an illegal bogus part that leaves you both
liable. I suggest that if you want to do this type of stuff, sell the
certified aircraft and try homebuilding.

I looked at the small brass ball valves at Home Depot. They sure are a
nice high quality ones - teflon seals and all.
NRP

nrp wrote:

I looked at the small brass ball valves at Home Depot. They sure are a
nice high quality ones - teflon seals and all.

I've had a failure rate of about 20% with the gate valves normally used for
water line shutoff valves. These are brass valves made in China or Indonesia.
The usual failure mode is leakage around the shaft collar. They can sometimes be
fixed by liberal applications of teflon sealant - attempting to tighten them up
usually strips the threads.

There's no way I would use a plumbing part from Home Depot or Lowes for an
application in which someone's life might depend on it.

George Patterson
He who tries to carry a cat by the tail learns something he can learn in
no other way.

George -
I've had a failure rate of about 20% with the gate valves normally
used for
water line shutoff valves. These are brass valves made in China or
Indonesia.
The usual failure mode is leakage around the shaft collar.

These are not cheap gate valves - at least the ones at HD I looked at.
They were 1/4 turn positive-stop ball valves with teflon or HDPE seals
thruout, and a good flow area. The ball appears to be stainless, and
the body is brass. I accept that they are not cerified and will
probably always be illegal, but I also understand the originator's
frustration. The older aircraft ones I've seen are really absolute
junk compared to these.

How about talking to a DER about one of the valves in question.


Dave

nrp wrote:

George -

I've had a failure rate of about 20% with the gate valves normally

used for

water line shutoff valves. These are brass valves made in China or

Indonesia.

The usual failure mode is leakage around the shaft collar.


These are not cheap gate valves - at least the ones at HD I looked at.
They were 1/4 turn positive-stop ball valves with teflon or HDPE seals
thruout, and a good flow area. The ball appears to be stainless, and
the body is brass. I accept that they are not cerified and will
probably always be illegal, but I also understand the originator's
frustration. The older aircraft ones I've seen are really absolute
junk compared to these.

"nrp" wrote in message
oups.com...
George -
I've had a failure rate of about 20% with the gate valves normally
used for
water line shutoff valves. These are brass valves made in China or
Indonesia.
The usual failure mode is leakage around the shaft collar.

These are not cheap gate valves - at least the ones at HD I looked at.
They were 1/4 turn positive-stop ball valves with teflon or HDPE seals
thruout, and a good flow area. The ball appears to be stainless, and
the body is brass. I accept that they are not cerified and will
probably always be illegal, but I also understand the originator's
frustration. The older aircraft ones I've seen are really absolute
junk compared to these.


You are so right, NRP, and these Home Depot valves are already in use as
aircraft fuel valves. They work perfectly. They are of high quality.
And they are made in Italy, not China or Indonesia. I know a Cub with three
of them in it -- one for each wing tank and one just upstream of the
gascolator. They have been altered to look like they were custom-made.

I have one of those original equipment valves like Michael Horowitz
repaired. I keep it around as a conversation piece just to show what a
leaky klunker it is, compared to a bolla valvola. A Taylorcraft owner
wanted to buy it at one time, but I told him he would be assuming a foolish
risk.

Michael Horowitz wrote:
: Back in December I posed a question about replacing the fuel cut-off
: valve in my 47 Tcraft with parts from HDepot.

Why not replace it with a fuel valve from a more modern airplane? Surely
a fuel shutoff from a Cessna 152 will work (forget the paperwork...).
The Cessna valve probably costs $200, but it would come with documentation
allowing its use in said Cessna. This would probably be a very simple field
approval.
Or am I totally nuts?
--
Aaron C.

"Gene Kearns" wrote:



I finally got the chance to talk to one of my students that is
restoring a 1939 BC-65 and he tells me that all of the fuel valve leg
work has been done and published in the Taylorcraft Magazine. Since
Imperial has gone Tango Uniform it was necessary to find replacement
parts that will cross over by specification. He didn't have the
numbers with him, but all of the parts are "tractor" parts. Follow the
instructions, fill out the 337, get an approval, and you have a legal
part for about ten dollars.


Gene - I see a conflict in what you are saying. Here you sound like
you are saying 'because it's tractor parts, I won't have any problem
with getting a 337 approved'

Previously you implied I'd need to use a valve with traceable
specifications.

It sounds like a conflict because a 'tractor part' isn't going to hve
traceable specs is it? - MIke

nrp wrote:

These are not cheap gate valves - at least the ones at HD I looked at.

Just checked them out. Made in Italy. Good to know there's some decent quality
available again. Thanks.

George Patterson
He who tries to carry a cat by the tail learns something he can learn in
no other way.