Help with diagnosis. Cracked block?
 

I'm at a loss. I bought a 2001 with 165,000 miles cheap for my son. It was running badly but running so I took a shot. Owner said it ate through water when it was driven for any distance but didn't overheat as long as there was water in the overflow tank. Oil leaks everywhere. We've pulled it all apart and the block is now out of the car. It was grimy and gritty everywhere internally. An inch of sludge in the sump and very gritty in the valley and heads. Main bearings look pretty good. Con rod bearings show wear and copper is showing on the upper shells. There is a big defect in one of the back cam bearings and the front looks pretty rough too.. When we pulled the heads, there was a lot of coolant in #6. Codes for misfires in #4 and #3. I don't see any major defects in the head gaskets that would allow coolant to migrate that far. Don't see obvious evidence of a slipped sleeve. The whole engine is stained orange. Dexcool? It had green coolant in it. We've had the heads done. I have studs. I have a new cam and lifters. Don't want to waste any more effort than necessary by moving forward with a crap block. What should i do next to be sure? Thanks you for any help.

Take the block and heads to a machine shop to be magnafluxed/flourofluxed. Worth the investment considering the condition it was in. I bought one with 252k but haven't been into the engine yet.

Very very low probability that you have a cracked block. The 00 and 01's were pretty reliable. If you really wanted to test it there is a block test kit that allows you to block off the water passages at the top of the block in place of the heads and pressurize the block through the water pump.