Reply #16 = 10W/40. Good discussion here - following.
Add 16oz more oil. Blow out that clotted artery and cross your fingers that the gaskets and seals don’t blow out!
Humans have blood thinners and antihypertensives for this condition. That’s all I got. Carry on please.
Good luck figuring this out before replacing the cam and head (and/or head cover).