How to check engine block after blown head gasket

[larrylarry]

I agree, but...5 & 8 are on opposite sides.

I hope he meant 6 & 8.

Use the straightedge technique first.
A Magnaflux check might be in order, if you can find someone with the equipment.

My bad!! I had this picture in my mind of that usual crack in the heads. It’s hell getting old.

 

[JordanZ28]

That's called the "Lifter Valley" . LOL

Yeah as others already mentioned, after cleaning the deck surface, check the cylinder head for straightness with a straight edge and feeler gauge. Check on several areas, straight and diagonal cross pattern, no more than .004" warpage, anymore than that and the cylinder head will require resurfacing.

The Block is more than likely okay, if its not it would be very obvious (at least on a clean block anyway)
Also check for stretched Head Bolt(s).

Did this engine overheated? new rebuilt perhaps?

Thanks for replying, I send the engine head for re-surface . The block has been cleaned and everything look ok hopefully , I will try to reassemble the engine and see .