Maybe you had some oil in the engine cooling jacket by accident. I would flush the cooling system till she’s 100% clean then reload with new anti freeze. I put in 100% good brand (Prestone) antifreeze not the mega expensive. No water in the cooling system makes it pretty impossible to corrode.
Fire her up again and see what happens.
What does the oil look like?
Engine Test Stand Playlist: https://www.youtube.com/playlist?list=PLwoxyUwptUcdqEb-o2ArqyiUaHW0G_C88 restoring my 1968 Firebird 400 HO convertible (Firedawg) 1965 Pontiac Catalina Safari Wagon 389 TriPower (Catwagon) 1999 JD AWS LX Lawn tractor 17hp (my daily driver) 2006 Sequoia 2017 Murano (wife's car) 202? Electric car 203? 68 Firebird /w electric engine 2007 Bayliner 175 runabout /w 3.0L Mercuiser__________________________________________________________
