Head bolt recession - advice welcomed

[dunclentdr1]

I was recently given a big valve twin cam of unknown history.

Upon inspection there is head bolt recession and in two place small splits in the metal close by.

I would welcome advice on this please, particularly on fixes.

Overall the head seems in good condition apart from this.

Thanks

David

[rgh0]

With that amount of recession the head is almost certainly too soft to reliably use. Have a look at the head face and see if there is an indentation where the head gasket fire ring seats as that is another indication of a very soft head.

Its possible to fit steel inserts to repair the damage from the bolt recession but generally not worth the cost as the soft metal in the head will continue to deform and not seal the head gasket.

Get the head hardness tested before doing anything with it.

cheers
Rohan

[knockoffnut]

This reminds me of the mechanic who used a big impact wrench to torque down wheel bolts, and then put a torque wrench on the bolts, pulled to listen for the click and then said "see they are good"...