The OTTO ME081542 bare cylinder head is core engine component for Mitsubishi 6D31 diesel engine fitted on Kato HD700 excavator. Made of high‑strength cast iron, it precisely forms combustion chambers, intake and exhaust passages for fuel‑air mixing and exhaust emission. Valve seat bores, valve guide holes, bolt holes and water‑oil galleries are strictly machined to OEM dimensions. Heat‑resistant structure withstands high combustion temperature and cyclic thermal shock, maintaining sealing performance under long‑time heavy‑duty construction‑site operation.