I bought a 1997 tracker with the engine out and disassembled.  The problem with the motor was the key way on the crank was damaged and had to be welded and reground.  Today I cleaned the block and found a Crack dead center on the main bearing of the number 3 cylinder.  I was told the engine ran well before the disassembly.  The Crack doesn't go through the oil hole.  With the bearing cap on would this give the block enough support to make the block usable?  The two cap bolts would straddle the crack.
Thanks.

I bought a 1997 tracker with the engine out and disassembled.  The problem with the motor was the key way on the crank was damaged and had to be welded and reground.  Today I cleaned the block and found a Crack dead center on the main bearing of the number 3 cylinder.  I was told the engine ran well before the disassembly.  The Crack doesn't go through the oil hole.  With the bearing cap on would this give the block enough support to make the block usable?  The two cap bolts would straddle the crack.
Thanks.

That looks like real crack, not a think crack.  How big can the crack get before it is detrimental to getting you out of the woods and back home?  Are you going to stop drill it?
I would say that you have a motor with two problems.

I was able to find another block for $100.00.  So I'll use it. 
Thanks for the reply.

That is a wise decision, especially for a rebuild.

An update:  The $100.00 block turned out to be in bad shape.  It had been rebored.  One of the main bearings was bad and metal had got into the piston bores.  I brought it back and exchanged it for a $200.00 block with crank, pistons, and rods.  I've taken this apart and everything looks good.  I will have it decked at a machine shop as the seller told me the reason the engine was pulled was because it had a blown head gasket.  The main bearings and rod bearings looked great so did the pistons and cylinder bores.  As with all my projects I will probably end up paying as much or more than a good runner would cost.  The cheap initial price is what always hooks me.  I'm learning new things and for me that's worth something.  This will be my first complete engine rebuild.

We found a crack in a cylinder sleeve that was presumably causing the water in oil issues.  And on the last Tracker with water in oil issues, after replacing the head gasket didn't work we scrapped the motor and started a transplant.  So cracks are not that rare to me.
I would agree that you will have as much in your project as a good runner would cost, and the cheap initial price has a sharp hook.  Good luck on the build.  We all enjoy reading a good build, a cheaper way of gaining second hand knowledge .

If this is your first rebuilt there are a few "gotchas" to be aware of - especially since you have multiple blocks and other bits lying around...

If you already know these, fine, if you don't, this may save you some grief and/or head scratching - keep the bearing caps (both rod & main), where they belong, do not mix them up - the caps are mated to the block and then line bored, they MUST go back where they came from.

When reassembling, be aware it's very easy to get the head gasket in backwards - get it wrong and you'll end up with the cam seized in the head - find the oil way near the front of the block/head and make sure the hole in the gasket is in the right place.

Thanks for the advice.  I've been doing what I do for over 35 years but I still listen to even the youngest new guy because there might be one grain of wisdom in what they are saying and even if they are wrong it might make you think in a different way to solve the problem.
I had to leave home today to go to work.  I won't be back for a month.  I'll be studying up on these trackers.  So when I get back I don't make the rookie mistakes.  Assume I don't know anything.  I'll read it all.
Thanks again.