I spent a couple of days replacing the heater core. I flushed engine and radiator. I still don't have heat and temp guage is still almost to red when I drive car. Both fans are working.
-Check your oil to see if its look milky, if it does, head gasket blown.
-Check thermostat to see if its serviceable by putting into the boiling water. The good thermostat should opens up.
-Check Radiator Cap will hold pressure.