cometic head gasket issue
FYI
During installation use a couple of light coats of Permatex Coppercoat to ensure a good water seal.
If any water seepage should occur allow the engine to heat cycle a few times, most likely it will seal itself once the gaskets form to the head and deck. If it continues to seep add a can of Justice Brothers Radiator Pepper Based Sealer Part # RSL/2 .