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Welcome Mile; Alons are terrific Aircoupes. Is yours one of the A2-A's that was put out originally without rudder pedals? The first hurdle to repairing your tank is to remove it from the aircraft. I have found that you may remove the Alon fuselage tank by first removing the right hand instrument panel and loosening any wiring that needs to be removed. Be sure to tag/mark any wiring you need to take loose so it will be put back the way it was. Once you have the right hand area clear, you can loosen the strap that holds the tank (I am assuming it is empty, but if not, drain the fuel BEFORE you loosen the strap). Then you can work the tank down, out of the filler neck grommet, and by turning it a little, you can pull it out through the opening left when you removed the right hand instrument panel. Once you have the tank removed, you need to clean it thoroughly and inspect it for signs of further deterioration other than the large crack you described. The last Alon tank I repaired had 5 separate pin hole leaks, plus a front corner that was corroded over an area about as large as a quarter. When I probed it, the material just disappeared and left a big hole. The tank can be repaired by soldering (low temperature aluminum welding using a propane torch) a patch over the crack, or by cutting a hole large enough to allow access to enable you to place a piece (s) on the inside with nut plates. You make a patch to go on the outside which is larger than the hole and drill the tank so that the patch can be fastened securely to the tank with screws into the nut plates you put on the inside. When you assemble the patch to the tank, you must use PRC 890 fuel tank sealer all under the patch. Another possibility is to have the crack welded, but that requires considerable expertise working with thin (the tank is made of .050 or .060) aluminum, and a TIG welding outfit. If you have access to someone who makes or repairs aluminum tanks, they may be able to help you. After the repair is complete, the tank must be pressure tested to ensure that there are no more leaks. Removing the sloshing compound will be/is a messy and tedious job. MEK will soften and eventually loosen the sloshing compound. I heard that it takes about 3 gallons of MEK used over a 2 to 3 day period to soften and remove the sloshing compound. I have not done it myself, but I have heard the process described. If you do it with the crack, you will have a problem with the MEK wanting to leak out of the crack, but I am sure you can figure out how to put the crack side up and minimize the leakage. In any case, the tank can be repaired, but if you have to pay shop rates to do all the above, you may be better off biting the bullet and buying that new tank. Good Luck Lynn Nelsen N99387 52FL --------------------------------- to unsubscribe send mailto:[EMAIL PROTECTED] ___________________________________________________________ T O P I C A http://www.topica.com/t/17 Newsletters, Tips and Discussions on Your Favorite Topics
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