So I pulled my engine to do a rebuild. For the most part it was in reasonably good shape. One little problem, though, was that the block is cracked. The cracks are coming from the part of the block into which the outer bolts from the main bearing caps for the crankshaft are threaded into. Apparently what can happen is that if the cracks propogate far enough up, the whole section that the bearing cap attaches to will separate from the block, and your crankshaft will either fall into the oil pan, or break since it is no longer supported in the middle. Not good! Anyhow, I've looked at about 3 other blocks, and they all have the same problem. Has anybody else seen this? Is it common? Should I throw it away and start over? Do I risk rebuilding it? I cringe at the thought of putting a gasoline engine in there. A little help please!!