I recently had a really bad ticking sound coming from under my timing belt cover after a timing belt replacement, so I removed all the covers and found something very unfortunate. Apparently my timing belt tensioner bracket sheared the heads off the two bolts that mount it to the block. Fortunately, I do not think the timing belt skipped, since the tensioner had been held in place by the covers.
Has anyone heard of these bolts shearing off? Even if I can extract them from the block, is that likely to happen again?