743 Kubota V1702 Cylinder Head Cracking

[Jackmv]

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Hi all, I recently had a head gasket blow on this 743 and was inspecting the head for cracks. I found these on this area which is below the injector. Each of the four cylinders has these cracks in the same spot. Technically this is a cracked head but I am not convinced it calls for a replacement. Anyone have any input or thoughts? Thank you.

 

[foton]

I am kinda scared of any cracks , but where those are at is a hollow chamber, I would think that the crack will stop when it hits a edge of the pocket. Now as long as a piece does crack off you should be ok, I think? I would go to a head reconditioning shop and get a pro's opinion.

 

[Phil314]

My thoughts, it's easier to replace a head than an entire engine. Especially since the head is already off.
It wouldn't take much for a small piece to break off. Like in the red circle.
It that jams between the piston and the cylinder wall, it would very quickly do significant damage to the wall, piston & rings.
I always try to look for the worst case scenario, because that's usually what happens to me when I ignore things.

 

[Tazza]

Cracks in your pre-coms are not a huge deal, they do crack, but are not a real issue, skim the head and throw a new head gasket at it.

I have yet to see one come through the workshop with a piece of pre-com fall out and cause damage, dropped valve seats yes, that that sure makes a mess of the head and piston, but not a pre-com.

 

[jp8775]

Does anyone have a photo of a crack where the heads usually crack needing replacement. They crack if they are not allowed to run a few minutes after running or over heating would like to see that crack.

 

[Tazza]

Between valves or valves to pre-combustion chambers.

Give the head a good rub with a wire wheel on a grinder in this area. 99% of the time, cracks are quite visible, but every so often they don't show up till the head is skimmed.

If your engine starts using coolant after over heating, it's likely the head has failed, but some times you get lucky and it's just the gasket.