Does this look right?

RudiGreyling · #1 12-19-2005, 02:31 AM

Hi Guys,

I haven't done any Alu Fuel Tube forming yet, I ordered one standard pickup from Vans, it arrived and looks good with the exception of the flaring where it is suppose to join. Looking at the other AN fittings the inside of the flare looks smooth and round. This one doesn't. It looks like it won't seal properly, it looks rough, is a little oval and the inside diameter abruptly change to not round around the top. I haven't done any flaring yet so I do not know. I do not want to seal the tanks up only to find that it is leaking or sucking air. Is it suppose to look like this or should I send it back to Vans?

PS: Anyone that can reference me to a link on the Best Practices on how to flare the Alu Fuel tubing would be appreciated.

Thanks you in advance,
Kind Regards
Rudi

DGlaeser · #2 12-19-2005, 07:00 AM

It looks like whoever did the flare did not use any lubrication on the mandrel. Chances are when you tighten it down it will seal just fine. If the sock came off easily (looks like it's ProSealed on), you could put your finger over the end of the tube and suck on the open side of the 90 degree fitting and see if it leaks. That joint doesn't see any suction unless the tube is blocked, which means you have bigger problems, so I wouldn't worry excessively about it. I would mention it to Vans though and see what they say.

Dennis Glaeser
7A

Steve · #3 12-19-2005, 07:04 AM

Could be the tube stop on the flare tool was improperly set. It looks like the OD of the flare is too large preventing it from slipping down inside the nut. Get a replacement pickup tube if that's the case.
Steve

osxuser · #4 12-19-2005, 11:54 AM

Quote:

Originally Posted by Steve

Could be the tube stop on the flare tool was improperly set. It looks like the OD of the flare is too large preventing it from slipping down inside the nut. Get a replacement pickup tube if that's the case.
Steve

Thats not the case. If you look closely, it's not the B-nut in the second picture, jut the little backup sleeve.

I would simply get some fine scotchbrite pad and run it in a circular motion in the flare to knock down any large ridges. Other than that I'm almost 100% sure that one will seal no problem when torqued.

az_gila · #5 12-19-2005, 07:22 PM

If you are still worried after reading all of these messages, this little baby will fix the problem for about a buck...

http://www.aircraftspruce.com/catalo...37fittings.php

They are good to have around... use one instead of the "a little bit more torque" technique to fix leaks....

gil in Tucson

RudiGreyling · #6 12-19-2005, 11:07 PM

Hi Guys,

Thanks for the information.

Seems most agree, clean it up and it will most probly seal good.

PS: I am still looking for a link to Flaring and AN tube fittings Best Practices, if you have one handy.

Kind Regards
Rudi

petehowell · #7 12-20-2005, 12:02 AM

Here is link to a car site. The practices are similar, but the tools and angles are not. It might help a bit. I could not find anything for aircraft.

Cheers,

Pete

http://www.joesfalcon.com/gentip2/gentip2.html

tacchi88 · #8 12-20-2005, 05:17 AM

Your fitting looks fine and it will seal. You should as someone already pointed, out, use a dab of lubricant. Any light oil will do. It can be burnished (smoothened) by simply using the mandrel with light oil and gently press it. I would refrain from using "seals" unless it's for the purpose of temporary repairs. The use of those seals is generally a result of a poor fit, worn fitting, or damage. Like stop driling, it is only a temporary repair. There have been cases where pieces of the "seal" actually blocked the line, due to the crushing action when tightening. You have a lot of time and money invested, if it doesn't seal properly, make a new one.
T88
A&P,IA, Tech Adv.