Hot Rods Flathead Crack?

For those of you with experience with flathead cracks.
Circled in red is the area where I have a crack. It took fluxing to have them show it to me but it is there. The block has been cleaned, flux'd and this was the only one found.
I'm being told by the shop several hundred dollars to attempt to fix it. They will try to stitch it then a pressure check to see if it worked.
Is this a crap shoot or?

 

Are you sure,,,,,,I can’t see a thing .

Tommy

 

Remove the seat, stitch it, then new seat and sleeve the cylinder. I'm sure it will be over a hundred, but several?

 

What Alchemy just said,,,,,should be great after that .

Tommy

 

Have them do it.

 

Desoto291Hemi I could not see it either. They powdered and magnets and there it is.
I'll try to get a better pic but it's hard to show.
Alchemy That's the shops suggestion.

There is a chance that the stitch doesn't work?

 

I can see it, but it's faint. It can be pinned as long as it doesn't go all the way down the bore. New valve seat and a cylinder sleeve, no problem.

 

I would clean up the cylinder wall so any crack can be detected. I would also be more worried about the broken studs. I wouldn't be too concerned about this block for a stock every day driver but if I was building an expensive high compression hot rod engine I would find a better block. In any event I certainly wouldn't throw it out. Clean it up, peen it and use it. I've seen much worse.

 

If you want a good look at the crack then use a liquid dye penetrant test with a white developer. Magnaflux makes kits. The colored penetrant is allowed to soak in for about 20 minutes or so, then the surfaces wiped clean with solvent then sprayed with a developer that is like a white chalk. The dye will bleed out of the crack into the developer and then it will show exactly where it is and where it runs to. The valve would have to come out for that dye pen check to see how deep it runs in the valve pocket of the casting. Take pictures early in the dye showing up in the developer. It will show the crack clear and eventually the dye will bleed out so far it loses definition. If you browse through this flathead porting thread you may see a cross section of the area where the crack is located and what is there for water channel and metal.
https://www.jalopyjournal.com/forum...to-nuts-pictures-details-and-opinions.420484/