X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 31 Jan 2011 14:21:53 -0500 Message-ID: X-Original-Return-Path: Received: from mta41.charter.net ([216.33.127.83] verified) by logan.com (CommuniGate Pro SMTP 5.4c2a) with ESMTP id 4832604 for lml@lancaironline.net; Mon, 31 Jan 2011 10:49:28 -0500 Received-SPF: pass receiver=logan.com; client-ip=216.33.127.83; envelope-from=troneill@charter.net Received: from imp09 ([10.20.200.9]) by mta41.charter.net (InterMail vM.7.09.02.04 201-2219-117-106-20090629) with ESMTP id <20110131154852.JQKK2629.mta41.charter.net@imp09> for ; Mon, 31 Jan 2011 10:48:52 -0500 Received: from wt01 ([209.225.8.41]) by imp09 with smtp.charter.net id 2Fom1g0040t7FYZ05FoqhU; Mon, 31 Jan 2011 10:48:51 -0500 X-Authority-Analysis: v=1.0 c=1 a=YWatrMyl0LkA:10 a=nKN5q7pN8I8A:10 a=Ia-xEzejAAAA:8 a=hOpmn2quAAAA:8 a=oCcaPWc0AAAA:8 a=3ejdIQl-l_W9JV8QkNQA:9 a=dMEchevuBrWvDZ8YjigA:7 a=he4_Vwuv3piGqI14PT3FxB1d68oA:4 a=QEXdDO2ut3YA:10 a=CVU0O5Kb7MsA:10 a=EzXvWhQp4_cA:10 a=hUswqBWy9Q8A:10 a=A9DA4FW9uCM2-Lvz:21 a=0dMCMMqL5-m42pxt:21 a=9bGdWno6CxhagAvZxT4A:9 a=mT4MF5NmzFazDJ7cDYUA:7 a=m4R5VDHUrBbnxtw9DQpldEzpk-oA:4 a=nMv4odikxLK1nEQx:21 a=TJQJ5iVyNVRss0G_:21 Received: from [69.26.248.6] by enhanced.charter.net with HTTP; Mon, 31 Jan 2011 10:48:46 -0500 X-Original-Date: Mon, 31 Jan 2011 10:48:46 -0500 (EST) From: troneill@charter.net X-Original-To: Lancair Mailing List X-Original-Message-ID: <1549056651.7713294.1296488930770.JavaMail.javamailuser@localhost> Subject: RE: [LML] How to find the leak - another method MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_7713270_2026912801.1296488926113" User-Agent: Laszlo Mail 3 X-SID: 41 X-Originating-IP: [69.26.248.6] ------=_Part_7713270_2026912801.1296488926113 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Thanks, Jim. That's a neat idea for my 'fix' file. In this case the leak is somewhere between the wing leading enge skin=20 and the front spar web. soi can't see in there. I'll check out what a=20 'sniffer' looks like. Maybe itwold fit in between the leading edge skin=20 and the front spar's web. Terrence On Mon, Jan 31, 2011 at 7:17 AM, Jim Nordin wrote: Empty the tank of fuel. Flush the inside of the tank with Freon (don=E2= =80=99t=20 let the FEDs know), pressurize it a tiny bit, seal it, then use a=20 =E2=80=9Csniffer=E2=80=9D to detect the very smallest micro leak. Flow plen= ty of air=20 over the wing areas for a while to remove residual Freon pockets before=20 your search begins. Freon=E2=80=99s molecular size (critical dimension is a= bout=20 5.3 angstroms) is close to pentane (6 angstroms I think I remember)=20 which means, if you can flow pentane, you can flow Freon. So if you find=20 a leak using a sniffer, you might have a gasoline leak there too. Hey, I=20 might be wrong about the numbers =E2=80=A6 it=E2=80=99s been a long time si= nce using=20 these dimensions etc, but the sniffer should work even if the numbers=20 are wrong. This method removes the volumetric, atmospheric, temperature=20 variation issues altogether and Freon doesn=E2=80=99t support combustion. J= ust=20 make sure there=E2=80=99s positive pressure (tiny amount) in the tank when= =20 searching for that micro amount of Freon. Plug all =E2=80=9Choles=E2=80=9D = into the=20 tank. On the overflow slightly pressurize the tank with freon, now=20 connect a small balloon and seal around the neck. If the tank leaks a=20 little because you didn=E2=80=99t seal it really really well, that=E2=80=99= s OK as long=20 as you find the leak before the tank is again at atmospheric pressure.=20 After you find the leak, remove the Freon or not. Is a lack of fuel sealer opening an area of exposure, have a crack in=20 the wing structure, what? The cause may be pointing to the appropriate=20 repair. Jim ___________________________________ From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of=20 Terrence O'Neill Sent: Sunday, January 30, 2011 9:32 AM To: lml@lancaironline.net Subject: [LML] Re: Weeping wing tank. super cool trick to fix it!!! Neat. I didn't know about the bubbles adn amplifying the sound. I made a manometer so I can limit the vacuum to about 6 inches water... and I just bought some PR-1005-L ... a quart. I think that'll be enough, as the leak seems to be in the upper part of=20 the front spar web. Doesn't leak when below 78 gallons in the tank. Many thanks. Terrence 235/320 N211AL On Jan 29, 2011, at 10:36 PM, randy snarr wrote: Terrence, Take a deep breath. I had a similar issue on mine and the cure was not=20 that bad. I have a trick that should help.. First the bad news, Remove the wing. (drain fuel first duh..) leave=20 about a pint in the tank. Once the wing is off you can find the leak by putting a small amount of=20 negative pressure on the tank and seal it up. You have to seal=20 everything off first. I would connect a tube to the fuel or vent line=20 and just suck on the tank with your mouth and then seal it off. You=20 dont need much. I found this completely by accident. You never get all the fuel out and=20 in this case that is ok. A pint of fuel in the tank is good for this trick. With a little=20 negative pressure on the tank, rotate the wing and force the fuel=20 around all the corners in the tank where the suspected leak is and=20 listen carefully with your ear. When the fuel covers the hole in the=20 tank you will hear the air bubbles passing through the fuel as it=20 enters the tank. The empty wing is like a drum and the sound is=20 amplified. I had a leak and found it at bottom front corner of the=20 tank where the tank close out rib meets the lower skin forward at the=20 spar. Now you know where the leak is.You can now remove the pint or so=20 of fuel and dry out the tank. I used an alum rod with paper towels=20 taped to the end to get it dry in the corner where gravity collects it.=20 Once it is DRY. orient the wing so the leak is where gravity will take=20 your sealer. I used the same gray epoxy based tank sealer lance=20 recommends. U used a large seringe ( like for a cow) and injected=20 about 1 cup of gray sealer as close to where the hole is through the=20 gas cap hole. You wont be able to see any of this but you can do it by feel. Move the=20 tank around slightly to completely cover the entire area where the=20 hole is. I would seal up the tank again and put the negative pressure=20 back on to push some goo into the leak hole for 20 minutes or so.=20 Release the negative pressure and Support the tank with the hole at=20 the lowest point and let it cure. Shazam, no more leak. Hope that helps.. Best, Randy Snarr 235/320 N694RS ( i mean real small as you can collapse your wing with too much!) "Flight by machines heavier than air is unpractical and insignificant,=20 if not utterly impossible" -Simon Newcomb, 1902 --- On Mon, 1/24/11, Terrence O'Neill < troneill@charter.net=20 >=20 wrote: From: Terrence O'Neill < troneill@charter.net=20 > Subject: [LML] Weeping wing tank. To: lml@lancaironline.net=20 Date: Monday, January 24, 2011, 5:57 AM This is a request for info on the possible similar experience of other=20 LNC2 builder-fliers... a wing tank fuel leak. The very slow leak through the front wing spar, when fuel leveel is=20 above about half way up, is of course uninspectable because of the=20 leading edge -- and further because it is possibly behind the root=20 area secondary web ... not to mention the fact that the spar web is=20 sandwich construction and the interior skin leak can propagate=20 spanwise to another portal in the forward web skin. So my question is, when I slosh-seal the tank, what is recommended as a=20 prep for the tank inner surface? I've read MEK and another TankPrep stuff. For sealant I've looked at PR-1005-L, and at the automotive (supposedly)=20 stuff, and phenol novolac. Any suggestions soulfully appreciated, for this worrisome job. Thanks. terrence N211AL LNC2 235/320. --=20 For archives and unsub=20 http://mail.lancaironline.net:81/lists/lml/List.html=20 ___________________________________ No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1204 / Virus Database: 1435/3412 - Release Date: 01/30/11 ------=_Part_7713270_2026912801.1296488926113 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
 
Thanks, Jim.  That's a neat idea for my 'fix' file.
In this case the leak is somewhere between = the wing leading enge skin and the front spar web. soi can't see in there. = I'll check out what a 'sniffer' looks like.  Maybe itwold fit in betwe= en the leading edge skin and the front spar's web.

Terrence

On Mon, Jan 31, 2011 at 7:17 AM,= Jim Nordin wrote:

 Empty the tank of fu= el. Flush the inside of the tank with Freon (don=E2=80=99t let the FEDs kno= w), pressurize it a tiny bit, seal it, then use a =E2=80=9Csniffer=E2=80=9D= to detect the very smallest micro leak. Flow plenty of air over the wing a= reas for a while to remove residual Freon pockets before your search begins= . Freon=E2=80=99s molecular size (critical dimension is about 5.3 angstroms= ) is close to pentane (6 angstroms I think I remember) which means, if you = can flow pentane, you can flow Freon. So if you find a leak using a sniffer= , you might have a gasoline leak there too. Hey, I might be wrong about the= numbers =E2=80=A6 it=E2=80=99s been a long time since using these dimensio= ns etc, but the sniffer should work even if the numbers are wrong. This met= hod removes the volumetric, atmospheric, temperature variation issues altog= ether and Freon doesn=E2=80=99t support combustion. Just make sure there=E2= =80=99s positive pressure (tiny amount) in the tank when searching for that= micro amount of Freon. Plug all =E2=80=9Choles=E2=80=9D into the tank. On = the overflow slightly pressurize the tank with freon, now connect a small b= alloon and seal around the neck. If the tank leaks a little because you did= n=E2=80=99t seal it really really well, that=E2=80=99s OK as long as you fi= nd the leak before the tank is again at atmospheric pressure. After you fin= d the leak, remove the Freon or not.
Is a lack of fuel sealer opening an area of exposure, = have a crack in the wing structure, what? The cause may be pointing to the = appropriate repair.
Jim <= /FONT>
 
 
___________________________________

From: Lancair Mailing List [mailto:lml@lancairo= nline.net] On Behalf Of Terrence O'Neill
Sent: Sunday, January 30, 2011 9:32 AM
=
To: lml@lancaironline.net
Subject: [LML] Re: Weeping wing tank.= super cool trick to fix it!!!
 
Neat.&n= bsp; I didn't know about the bubbles adn amplifying the sound.   =
I made a manometer so I= can limit the vacuum to about 6 inches water...
and I just bought some PR-1005-L ... a quart.
I think that'll be enough,= as the leak seems to be in the upper part of the front spar web.  Doe= sn't leak when below 78 gallons in the tank.
Many thanks.
 
Terr= ence
235/320 N211AL <= /FONT>
 
 
= On Jan 29, 2011, at 10:36 PM, randy snarr wrote:



Terrence, <= /FONT>
Take a deep breath. I ha= d a similar issue on mine and the cure was not that   bad.
I have a trick that should h= elp..

First the bad news, Remove the wing. (drain fuel first duh..) = leave about a   pint in the tank.

Once the wing is off you= can find the leak by putting a small amount of   negative pressu= re on the tank and seal it up. You have to seal everything off   = first. I would connect a tube to the fuel or vent line and just suck on the=    tank with your mouth and then seal it off. You dont need much.=
I found this completel= y by accident. You never get all the fuel out and in   this case = that is ok.
A pint of f= uel in the tank is good for this trick. With a little negative   = pressure on the tank, rotate the wing and force the fuel around all the&nbs= p;  corners in the tank where the suspected leak is and listen careful= ly with   your ear. When the fuel covers the hole in the tank you= will hear the air   bubbles passing through the fuel as it enter= s the tank. The empty wing is   like a drum and the sound is ampl= ified. I had a leak and found it at bottom   front corner of the = tank where the tank close out rib meets the lower skin   forward = at the spar. Now you know where the leak is.You can now remove the &nb= sp; pint or so of fuel and dry out the tank. I used an alum rod with paper = towels   taped to the end to get it dry in the corner where gravi= ty collects it. Once   it is DRY. orient the wing so the leak is = where gravity will take your   sealer. I used the same gray epoxy= based tank sealer lance recommends. U used   a large seringe ( l= ike for a cow) and injected about 1 cup of gray sealer as   close= to where the hole is through the gas cap hole.
You wont be able to see any of this but you can do= it by feel. Move the tank   around slightly to completely cover = the entire area where the hole is. I   would seal up the tank aga= in and put the negative pressure back on to push   some goo into = the leak hole for 20 minutes or so. Release the negative   pressu= re and Support the tank with the hole at the lowest point and let it &= nbsp; cure.
Shazam, no = more leak.
Hope that he= lps..
Best,
Randy Snarr
235/320
N694RS


 ( i mean = real small as you can collapse your wing with too much!)

"Fl= ight by machines heavier than air   is unpractical and insignific= ant, if not utterly impossible"
<= FONT FACE=3D"Times New Roman" SIZE=3D"3" COLOR=3D"#000000" LETTERSPACING=3D= "0" KERNING=3D"0">-Simon Newcomb, 1902

=
--- On Mon, 1/24/11, Terr= ence O'Neill < = troneill@charter.net= > wrote:

From: Terrence O'Neill < troneill@charter.net>=
Subject: [LML] Weeping= wing tank.
Date: Monday, January 24, = 2011, 5:57 AM

This is a request for info on the possible similar ex= perience of other LNC2   builder-fliers... a wing tank fuel leak.=

The very slow leak through the front wing spar, when fuel leveel i= s above   about half way up, is of course uninspectable because o= f the leading edge --   and further because it is possibly behind= the root area secondary web ... not   to mention the fact that t= he spar web is sandwich construction and the   interior skin leak= can propagate spanwise to another portal in the forward   web sk= in.

So my question is, when I slosh-seal the tank, what is recommend= ed as a prep   for the tank inner surface?
I've read MEK and another TankPrep stuff.

For sealant I've looked at PR-1005-L, and at the automotive (supposedly= )   stuff, and  phenol novolac.
Any suggestions soulfully appreciated, for this wor= risome job.
Thanks.

terrence N211AL
LNC= 2 235/320.


--
 
 = ;
_____________________= ______________

No virus found in this message.
Checked by AVG - www.avg.com=
Version: 10.0.1204 / Vi= rus Database: 1435/3412 - Release Date: 01/30/11
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