Matronics Email Lists :: View topic - 912 Oil Leak

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

912 Oil Leak - cracked fitting

Matronics Email Lists Forum Index -> Kitfox-List

View previous topic :: View next topic

Author Message

Fox5flyer
Guest

Posted: Mon Dec 18, 2006 3:46 am Post subject: 912 Oil Leak - cracked fitting

I'm a plumber by trade (been called other things  though) and what you describe is a common phenomenon that I've wasted many many  hours trying to find the cause.  It happens with not only aluminum, but  pvc, plastic, steel, and cast iron.  The crack is perpendicular to  the female threads and generally is nearly invisible and usually is  caused by the male fitting being screwed in too tight and it may not show itself  for years.  The natural tendency is to take it apart, clean it up,  apply some sort of accapuckky or Teflon tape, or whatever, retighten it, then  watch it begin to leak again.  So what do we usually do?  Tighten it  up some more! and pipe threads being tapered as they are it only widens the  crack and exacerbates the leak.  

 This is a good lesson to all of you out there who  experience a small persistent leak in pipe thread type fittings.  Get the  part out on the bench under a good magnified light and eyeball it very closely  while tightening the fitting.  It's usually visible under those  conditions.  Better yet, some dye penetrant will show it up  too.

 Thanks again for the report Rexter.

 Deke

  

 [quote]   ---

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

dave

Joined: 22 Sep 2006
Posts: 1382

Posted: Mon Dec 18, 2006 4:08 am Post subject: 912 Oil Leak - cracked fitting

Deke , 

 You are right the NPT  thread is tapered and  where the female thread is in a cast part they are prove to cracking from  overtightening mostly. If a new thread can be welded on -GREAT !!   If  not just goop it up and hope for the best.

   

 I am not an advocate of teflon tape for fuel and  /or hydraulic lines as it will  cause clogging as the tape "threads " off  in strands sometimes. If you careful using it you might be ok but I can cause  issues.   I find that plumbers putty in sticks works well and read th  label to ensure it good for gas an oils.   Teflon tape Can break down  when exposed to Gas and oils.

 I have seen too often teflon tape pieces caught in  gascolators.  

  

 I know many use it sucessfully without an issue but  there are issues than can arise and caution is warranted.

  

 Dave

  

  

 [quote]   ---

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

_________________
Realtime Kitfox movies to separate the internet chatter from the truth
http://www.youtube.com/user/kitfoxflyer
Hundreds of Kitfox Movies
Most viewed Kitfox on youtube
Most popular on youtube
Highest rated on youtube

smokey_bear_40220(at)yaho
Guest

Posted: Tue Dec 19, 2006 6:04 am Post subject: 912 Oil Leak - cracked fitting

I had to buy a new gascolator for this too.  I could

only get 3 threads turned into mine with the pipe

fitting to hose coupling.  Thought that wasn't enough

for security and to prevenbt leaks.  I cut the threads

a bit deeper to get more turns in.  Instead the

fitting hit the interior of the gascolator and split

it open.



I've been called a plumber, but....



I have been using teflon paste on the outer threads on

my plane's fittings instead of tape.  Tried blue

colored auto store sealant first (ATV?) but had 7

leaks with it on the first try with fuel.  So far this

has worked and no junk in the lines.  But you must be

careful to only paste the last few threads.



A non-plumber's 2 cents worth.



Kurt S.



--- dave <dave(at)cfisher.com> wrote:



 	  Quote: 	
		   Deke , 

 You are right the NPT  thread is tapered and where

 the female thread is in a cast part they are prove

 to cracking from overtightening mostly. If a new

 thread can be welded on -GREAT !!   If not just goop

 it up and hope for the best.

   

 I am not an advocate of teflon tape for fuel and /or

 hydraulic lines as it will  cause clogging as the

 tape "threads " off in strands sometimes. If you

 careful using it you might be ok but I can cause

 issues.   I find that plumbers putty in sticks works

 well and read th label to ensure it good for gas an

 oils.   Teflon tape Can break down when exposed to

 Gas and oils.

 I have seen too often teflon tape pieces caught in

 gascolators.  

 

 I know many use it sucessfully without an issue but

 there are issues than can arise and caution is

 warranted.

 

 Dave


	


__________________________________________________

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

dave

Joined: 22 Sep 2006
Posts: 1382

Posted: Tue Dec 19, 2006 7:38 am Post subject: 912 Oil Leak - cracked fitting

Kurt,  why have you NOT been using  teflon tape ?

Dave

---

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

pwmac(at)sisna.com
Guest

Posted: Tue Dec 19, 2006 7:55 am Post subject: 912 Oil Leak - cracked fitting

Loctite sells a thread sealer for fuels. Not the usual stuff. A quick 

call to Permatex engineering will give you the part number. Get 

the  phone number off any tube of Loctite. This stuff IMO probably 

works better than teflon tape or teflon paste. Having said that I 

still use both for my plumbing projects. The imported (China) steel 

pipe fittings are so roughly machined that the paste is the only 

thing that works. Such it is when living in Mexico = low quality fittings.

I am not an advocate of gascolators especially if you have the behind 

the seat Header tanks as it has a very large sump with a quick drain 

to accomplish the same function as a gascolator, but has to be used 

with a filter between the header and the engine.

We sure got a good input on the cracked housing where the sensor screwed in.

Regards, Paul

=====================

At 06:04 AM 12/19/2006, you wrote:

 	  Quote: 	

I had to buy a new gascolator for this too.  I could

only get 3 threads turned into mine with the pipe

fitting to hose coupling.  Thought that wasn't enough

for security and to prevenbt leaks.  I cut the threads

a bit deeper to get more turns in.  Instead the

fitting hit the interior of the gascolator and split

it open.

I've been called a plumber, but....

I have been using teflon paste on the outer threads on

my plane's fittings instead of tape.  Tried blue

colored auto store sealant first (ATV?) but had 7

leaks with it on the first try with fuel.  So far this

has worked and no junk in the lines.  But you must be

careful to only paste the last few threads.

A non-plumber's 2 cents worth.

Kurt S.

--- dave <dave(at)cfisher.com> wrote:

 > Deke ,

 > You are right the NPT  thread is tapered and where

 > the female thread is in a cast part they are prove

 > to cracking from overtightening mostly. If a new

 > thread can be welded on -GREAT !!   If not just goop

 > it up and hope for the best.

 >

 > I am not an advocate of teflon tape for fuel and /or

 > hydraulic lines as it will  cause clogging as the

 > tape "threads " off in strands sometimes. If you

 > careful using it you might be ok but I can cause

 > issues.   I find that plumbers putty in sticks works

 > well and read th label to ensure it good for gas an

 > oils.   Teflon tape Can break down when exposed to

 > Gas and oils.

 > I have seen too often teflon tape pieces caught in

 > gascolators.

 >

 > I know many use it sucessfully without an issue but

 > there are issues than can arise and caution is

 > warranted.

 >

 > Dave

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

smokey_bear_40220(at)yaho
Guest

Posted: Wed Dec 20, 2006 6:08 pm Post subject: 912 Oil Leak - cracked fitting

Hi Dave,



I found that the threads can cut the tape into little

strings that flow downstream and clog up the works. 

If you remove a fitting that has been taped, you can

often find that happened.



I have used it in a few places, but very carefully

covering only the outermost threads that connect.



The direction you wrap it in counts too.  Wrap it so

that it tightens as you thread it in or it will bunch

up.



Kurt S.  S-5



--- dave <dave(at)cfisher.com> wrote:

 

 	  Quote: 	
		   Kurt, why have you NOT been using teflon tape ?



 Dave


	


__________________________________________________

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

dave

Joined: 22 Sep 2006
Posts: 1382

Posted: Wed Dec 20, 2006 6:20 pm Post subject: 912 Oil Leak - cracked fitting

Kurt-- yes I feel the same as I posted the other day  here .

Dave



<

Sent: Monday, December 18, 2006 7:07 AM

Subject: Re: 912 Oil Leak - cracked fitting

Deke ,

You are right the NPT  thread is tapered and where the female thread is in a 

cast part they are prove to cracking from overtightening mostly. If a new 

thread can be welded on -GREAT !!   If not just goop it up and hope for the 

best.



I am not an advocate of teflon tape for fuel and /or hydraulic lines as it 

will  cause clogging as the tape "threads " off in strands sometimes. If you 

careful using it you might be ok but I can cause issues.   I find that 

plumbers putty in sticks works well and read th label to ensure it good for 

gas an oils.   Teflon tape Can break down when exposed to Gas and oils.

I have seen too often teflon tape pieces caught in gascolators.



I know many use it sucessfully without an issue but there are issues than 

can arise and caution is warranted.



Dave>

---

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

eskflyer(at)lvcisp.com
Guest

Posted: Wed Dec 20, 2006 6:39 pm Post subject: 912 Oil Leak - cracked fitting

read service letter #45   reiterates what Kurt is aying DO NOT USE TEFLON 

TAPE.

http://www.sportplanellc.com/support/service_letters/sl45.htm



look under fuel line fab #4

John Perry

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

Float Flyr

Joined: 19 Jul 2006
Posts: 2704
Location: Campbellton, Newfoundland

Posted: Thu Dec 21, 2006 6:31 am Post subject: 912 Oil Leak - cracked fitting

When I ran a photo production lab I had to deal with many different pumps.

Most of them had screw in pipe fittings.  I started off using T-tape (never

on the first few threads) more often  than not there was no problem.  With

one pump the manufacturer stated in the install manual not under any

circumstances to use T-tape.  Only to coat the a few of the threads with a

light coat of a special heat and chemical resistant RTV.  Again making sure

that nothing touched the first few threads.



My bosses father was a retired pipe fitter.  He insisted I use T-tape.  I

called the pump manufacturer and they told me if T-tape was used, the pump

housing would crack within ten hours.  I told the bosses father this and

cannot mention his reply without completely fracturing our PG rules.  I went

ahead and used the sealant recommended with no problems for many hours.



Just before I left that lab the boss picked up another processor with the

same pumps in it.  A fellow who was hired to replace me (Another story), was

told to install it.  The bosses father was to assist him.  Everything was

installed with  T-tape.  Even though I was told my assistance and opinions

were un-welcome I suggested they fill the machine with water and run it for

a day or so while checking for leaks, adjusting belt tensions, calibrating

temperatures etc.....  I got told....Again...  My last words as I left work

that night was they were to remember I had nothing to do with the

installation and it wasn't responsible!



The next morning I walked into the lab, in the basement of the building, to

find it ankle deep in very caustic chemicals.  The only fittings that didn't

fail were on the wash tanks (no pumps)  I calculate the use of T-tape cost

the company about $5000.00 in lost chemicals.  It would have been a factor

of ten if any one had let the spill out of the bag. 



The moral of the story... Yes Virginia there is a moral,  it is to do what

the OEM says.  I believe in this case that means the use of a special

sealant.



Noel



[quote] --

- The Matronics Kitfox-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Kitfox-List

_________________
Noel Loveys
Kitfox III-A
Aerocet 1100 Floats

Display posts from previous:

	Matronics Email Lists Forum Index -> Kitfox-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum