Leak Repair
I should just order this repair kit now. I hate this part so much.
Actually the repair kit issue is really not too bad. It is easy to cut the hole and easy to put on the cover when through. There are several issues though. I have been into my tank now for the THIRD time to fix these leaks. Each time it still leaked but it appears now I have it licked. I have caps on all the AN fittings and filled the tank with fuel BEFORE putting it back on the plane. You just cannot see minor seeps using the balloon and soapy water test...trust me on this. It is no fun putting that tank back on after a successful balloon test and then having to take it back off THREE times because it oozes gas.
1. Make certain ALL the old proseal fillet is removed and make sure the bare aluminum on which you will replace the fillet is CLEAN, It may look clean, but there are invisible deposits from the gas still left in the tank that will prevent a good seal with the new proseal.. Cleaning the proposal off is very difficult. Once you get most of it, MEK on a cloth will dissolve the thin film that is left. Get it all. DONT try to put a wider fillet on top of the old fillet. Did not work for me.
2. You can put the new proseal on with Popsicle sticks but 3/4" wide tongue depressors are necessary to get a good fillet profile. These are wider than Popsicle sticks and available on Amazon "Karlash Large Wax Sticks, Wood Waxing Craft Sticks Spatulas Applicators for Hair Removal Eyebrow and Body (Pack of 100) ". for$ 6.99. The Popsicle sticks just wont make a wide enough fillet.
3. Make some sort of cardboard or wood frame to put around the tank and cover it with a blanket, sealed as well as possible to preserve the heat to warm the tank to help cure the proseal. if you can get the tank to 100 to 120F it will cure overnight, otherwise at room temp it will take three days. If colder, it could take even longer. You can check the temperature with a laser thermometer. Instructions say the time to cure will decrease 50% for each 10 deg F above 70F. and double the cure time for each 10 deg below 70F.
4. All my leaks were in the tank bottom somewhere, so I only repaired the bottom seams in the bays that leaked. In my tank that was the bay at the wingtip end and the bay at the fuselage end.
5. When you put the back repair covers on smear a THIN coat of proseal on the back baffle surface and on the cover surface. when inserting the sealed blind rivets in the kit, Smear proseal on the shaft of the rivet before insertion to insure gas can't migrate down the shaft of the rivet.
6. I stopped some seeps on top rivets with Loctite 290 wicking Loctite. You could try it, just make sure there is no gas in the tank at that level and leave the filler cap loose so no pressure can build while it cures.
Good luck. Ed