weeping fuel around rivet and syringe
 

I have one weeping fuel rivet on the top of my left wing about 10 inches from inboard edge on the aft most row. I see a faint stain after a couple weeks of flying. The wing is unpainted but I'm getting ready for paint so I need to fix the rivet. I'm posting this because of the surprising result in application of the proseal. On a whim I decided to try a syringe to force proseal from the outside inwards around the rivet. I cut the end tip from the syringe and left the thin wall in place. I thinned the proseal with acetone. Here's the surprising part, I was able to apply all the force I could muster onto the syringe to force the proseal in to the rivet without the proseal squiring out and making a mess. I was amazed. I know I had at least 50 lb on the syringe, syringe area ~ 0.5 sq inch, so pressure on the proseal = 100 psi. The end area of the syringe thin wall created a much better seal than expected. The pressure inside the syringe is transferred thru the thin wall of the syringe and makes the seal. I don't know if this will fix the weeping rivet but I know if this pressure could not force the proseal in that nothing will. In the picture the proseal has been cleaned from the end of the syringe to view the size of the hole. Note, I tried the loctite fix previously but that did not work.

Please post your results. I have a few of those pesky buggers too.

Something I know will work when you have one or two weeping/leaking rivets.
You can drill out the rivet and clean the hole very well with MEK/MPK. Get the proper Cherry Lock or Max rivet and cover it in proseal and also put a dab of pro seal in the hole before pulling the rivet. Let the proseal fully cure before filling tank with fuel.

This should fix the leak and I guarantee that one rivet butt in your tank will not cause you any issues as long as you installed a finger screen on your pickup tube. The shop head of a 3/32" rivet is too big to fit thru the screen and will not block off the fuel flow thru the screen. I know that a loose rivet butt in the tank may be very controversial and may not be for the faint at heart, but I personally know that it works and it sure beats pulling and opening a tank for one or two pesky rivets.

Now if you have leaking rivets all over your tank, this procedure is not the fix. You should pull the tank, open it up, clean and seal the leaks from the inside.

Vacuum?
 

Steve,

When you tried the locktite, did you apply a vacuum to the tank?

T.

yep, I had vacuum on the tank with the loctite. this one must be stubborn.

agree, that is plan B if I need it.

the tank has been full for the past several days both sitting and flying. the syringe method seems to have stopped the leak on this rivet.

Bravo
 

Good to know Steve... thanks. Pictures?

Also...
 

If swag in the tank is really bothersome, you can pull the tank, inject plenty of sealant in the hole, install the rivet, the shake the rattler around until it hits the sealant. This also makes it possible to inject more effective sealant, as you can make gravity work for you.

seems safer
 

to apply pressure (as Steve is doing with his ProSeal syringe) to force Loctite into the rivet area than to pull a vacuum and try to suck it in. The tank will withstand far more pressure differential with local external pressure than what can be generated by pulling a vacuum on the entire tank without deformation. Maybe a syringe with tip ground-off and an O-ring on the end to make an air seal around the rivet factory head we're trying to force the Loctite under?

-Stormy

contemplating this fix for years but never seem to get around to it.