Initial startup cooling system troubles

Ugh. Maybe something was left in the block or heads water jacket from cleaning? Drain, pull the block plugs for sure. Evaporust makes this cleaner, pricey at $20.- at Wally Mart, but they have a good rep.

https://www.walmart.com/ip/Evapo-ru...cgkrPrmVHBTdfXNPwvlSjIg_3zCj7iOcaAhzMEALw_wcB