AC 175 Diesel cracked block opinions

Bought a nice low hour original paint 175 diesel earlier this year that has a crack in the block. Previous owner had it 25 years and said the block cracked about 20 years ago. I didn't get a clear answer on why it cracked, it seems it is a frost crack, but don't know for sure. No water gets into the oil, previous owner put JB weld over block, but the JB weld has since cracked. Owner said he could run it for an 8 hour day and it would lose very little antifreeze. When I got it, I ran it for about 3 hours and it lost almost no antifreeze so that story seems to be true. However, I changed antifreeze with a heavy duty diesel antifreeze and ran it for about another 3 hours and it seems to have deteriorated the JB weld some more and started leaking more.

I could JB weld it back up and continue to run it, I don't really use it much, but would someday like to fix it right. Replacing the block would probably be the best option, but it runs fantastic the way it is right now. I've ruled out welding it. There is something call metal stitching, but that looks costly and time consuming too and I don't know if that would fix it 100%.

I'm curious about other people's opinions would be for fixing or not fixing the block.

I'm 100% convinced this is truly a lower hours tractor (2,400 hours), by the way it runs and drives and the overall tightness of everything.

Would anyone have a good correct block, it's the 248ci.

It appears to be very close to a main engine oil galley, as evidenced by the oil pressure sender just below the crack, which leaks coolant.  I have plated a couple of tractor pulling blocks years ago, but they were flatter and not as contoured as this one is from front to rear.  As the engine works, that crack is trying to spread apart from the crankshaft pushing down and the cylinder head lifting up. If there was any way to get some good weld on it to keep it from spreading, then more epoxy/goop would last longer because the crack would stay shut.

Get a can of that spray on stuff they advertise on TV that they make a bottom for a boat out of a screen door,ought to do the trick.

There’s a 248 block on e-bay for $500. They want $175 for shipping, but it’s in Waukesha, WI, so picking it up might be an option.

Thanks for the comments, that gives me some more to think about. I did just check out the block on Ebay.......that is brand new still with the crate. That sounds tempting, but it's probably newer than the one I have, not sure what may have changed over the years.

What I would do is to have someone who has a magnaflux machine, and knows how to use it, use it to find the ends of the crack.  Then talk with a good welder, he will be able to advise you better.  Important thing is to stop the crack from spreading further.  Once your welder advises you on what to do, take his advice...