For a permanent repair, look into the "Lock-N-Stitch" system. It involves stop-drilling both ends of a crack, and installing a series of overlapping threaded plugs with thread sealant on them to eliminate the crack and replace it with solid metal. It's labor-intensive, and somewhat expensive, but it's very effective.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!