plugs are out. the head is off. evidence of oil leaking from gasket with gummed up black appearance,, but coolant looks green and some oil still in oil pan.
Initially, a hole in the oil pan caused all of the oil to leak out. Lost compression. Repaired the hole, added oil, and engine started – sounded ok. When it heated up however, on the highway, there was knocking, and a big puff of smoke came out of exhaust when the piston seized, power lost, and engine would not turn over. car was towed. Thermostat never showed high temperature, although oil was smoking.