Crack at head bolt location?

[UNCC Grad]

While attempting to replace and retorque my head due to a leaking HG, I noticed that in the location of cylinder 6 the last head bolt mounting surface of the head had two surface cracks right where the flange of the head bolt mates to the head.

Has anyone else seen this before and is it a huge concern? If I pull the head and have it decked for a new HG I guess they could fix it but is it really worth it? Just wondering if a replacement head is a btter route to take.

[Madhatter]

Could certainly be. At the worst it extends through the head, or the crack may continue to develop and release some tension on the bolt which might blow the gasket. Can you see how far down the cracks might progress through the bolt hole?

If its just galling because someone didn't lube the washer when they tensioned the head, it's not so bad. If it really is some cracks spreading, might be a bigger issue. It could even be a sign the alloy has softened and/or is porous. So at the least I reckon you need to have a cylinder head guy check it out for sure. Might end up being cheaper to pickup another good head.

[jlevie]

Have a good machine shop check out (and surface) the head. Point out your concern so they will carefully (probably using dye penetrant) for cracks.