OK, after my brother's engine hydrolocked and bend a rod (we assume), we have run it for all of 60 seconds, tops.

Before hand, it burned no oil (just water!), ran great and reliable.

What do you guys think are our chances that one can just take the engine down, replace the lower intake gasket, the bent/damaged parts, and not have to replace/rebuild the whole thing?

Does block itself usually get damaged in a hydrolock? Will there be scoring in the cylinder from just a few seconds of running?

Thanks in advance...

 

At the minumum you should replace the bearings, rings, hone the cylinders, check the heads for flatness, and a valve job. Remember to remove the heads before you remove the bearing caps or the block will distort.