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Gday All. I am in Australia and have a OKA (an Australian built 4X4. Only 446 built ) and I have re-powered will a Cummins 6bt.
I had replaced the head about 10 months ago,using the same head bolts as they where still well within tolerance and have done about 5000 kms.
I have pulled the head off again and found pitting around where the gasket seals around the bore, but all the way around. I have attached A photo
(I hope it comes out) It appears to be most on the intake manifold side near the head bolt between two bores. There is signs of rust in these bolt holes as well but not the others. The gasket has no signs of water leaking from the water jacket on either side.
My the theory that the water is leaking through the gasket lamination's. The side of the gasket on the head has a grove next to the metal ring that seals around the bore and it appears that water may be sitting in it.
Has anyone had this problem or any other ideas what the problem might be.
Any help would be greatly appreciated.
Cheers Peter.

PS Sorry, I am not real tech smart, I had listed it under the wrong heading. :confused:
 

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Why did you pull the head off again? What symptom caused you to do that?

Could very well be head gasket failure inbetween the MLS layers. If the head bolts measured within stretch spec, then that shouldn't be the cause of your issue, but improper torquing could be.

You definitely need to resurface that head to remove the pitting. Curious if the same pitting exists on the head surface.

For a plan, I'd have the head resurfaced, block deck checked, then put it together with a cummins brand head gasket. Go through the torque procedure, and let the motor sit overnight. Check the torque one more time when you're done. If you can afford it, ARP head studs would be a welcome addition, but certainly not necessary, assuming you have a stock-ish turbo and injection setup.
 

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Not on a B series, but I have seen that problem on other engines when there is insufficient clamping force on the head.

During combustion, the head squirms and leads to fretting of the components. Over time the pictured groove results.

As was mentioned, the proper fix is to plane the grooved surfaces...
 

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Yes Goat, we've seen that just recently on another engine. One big issue is getting the torque on the head bolts correct. If the torque wrench isn't up to specs then you can be off quite a bit which leaves the head gasket a bit loose. To me, although they cost a little more, studs are far superior that the factory head bolts. That and use a torque wrench that has accurate specs.
 
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