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Fuel Leak

Bootscooter

Active Member
Hi All,

I have recently developed a weeping fuel leak between the fuel drain flange and the wing skin.

They are QB wings and I have just done 50 hrs TT.

Can anyone help out on the best fix on this? Is it just a case of going in through the fuel sender panel and redoing the proseal

BTW loving flying this aeroplane!!!!

Brgs Chad

1D3526B6-BB17-4DE8-84A1-EEB469CFB289-257-00000028C9FB227F.jpg

photo-1.jpg
 
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You are correct, drain tank, pull tank, make sure it is fully drained, remove cover plate, tap a cloth over cover plate so air can get into tank but nothing else, let tank dry for a few days, put pro-seal over and around affected area, replace cover and seal, re-install tank and wait a week before adding fuel.
 
Hi Chad,

Your best bet is to remove the tank to fix it as Russ said.
I would just like to add to the above. While you have the tank off, I think it would be best to test for leaks with something like the Vans Fuel tank test kit, and soapy water. This way you can see what rivet/rivets need some pro-seal.
You wouldn't be happy if you went at it blind and just put pro-seal at random spots, re-fit the tank back onto the plane and still find more leaks.
 
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Rather than just adding sealer to the rivet heads (may or may not fix the problem), you might be better off to drill out the fitting, carefully pry it off, and start over, making sure to get adequate sealant between the fitting and skin.

Regardless of your approach to the repair, when you re-seal the fitting don't forget to leave paths for the water to drain, like this:
FP02102012A0004E.jpg
 
Loctite

Gday Chad,

Looks like only a very small weep.

Id try the loctite trick first.

I had a very small leak on the rear baffle at first pressure test. Sucked in some wicking loctite - all fixed.

300hrs leak free now.

Cheers!
 
Leaking Fuel Tank

Make sure that your leak isn't coming from the drain itself. I had a similar issue when a piece of crud found its way between the O ring and the seat in the drain. It dripped in flight and left a blue ring around the flange. Removed the drain and cleaned it with high pressure air, put some fuel lube on the threads and reinstalled. Don't over tighten as the lesson is painful and dirty. Not a drop of fuel in 60+ hours.
 
This works-

Gday Chad,

Looks like only a very small weep.

Id try the loctite trick first.

I had a very small leak on the rear baffle at first pressure test. Sucked in some wicking loctite - all fixed.

300hrs leak free now.

Cheers!

Just fixed a Cherokee tank with the above technique- watch the air pressure...
 
Make sure that your leak isn't coming from the drain itself. I had a similar issue when a piece of crud found its way between the O ring and the seat in the drain. It dripped in flight and left a blue ring around the flange.

Ditto. I serioulsy doubt it is the flange.
 
I had this exact issue too. sumpped fuel once and no further issues. (knock on wood)

Make sure that your leak isn't coming from the drain itself. I had a similar issue when a piece of crud found its way between the O ring and the seat in the drain. It dripped in flight and left a blue ring around the flange. Removed the drain and cleaned it with high pressure air, put some fuel lube on the threads and reinstalled. Don't over tighten as the lesson is painful and dirty. Not a drop of fuel in 60+ hours.
 
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