Cummins 4BT – Cylinder Head Cracks – Reuse Guidelines

These guidelines apply only to cracks extending from the injector bore to the intake valve seats. Replace cylinder
heads which exhibit valve bridge cracks in any other location.

The reuse guidelines for a cylinder head with a crack extending from the injector bore to the intake valve seat
are as follows:
If the crack does not extend into the valve seat, the cylยญinder head is reusable.

If the crack extends into or through the valve seat, the cylinder head must be repaired by installing a valve seat
insert per the Alternative Repair Manual, Bulletin No. 3810234.