Ok today was project day i replaced my heater core in my 77 ford F150 it was a task at hand. After i installed it i topped off my fluid and i started it up. I left the radiator cap off to burp the bubbles out topped it off lil bit more and closed the cap. Now here is my problem. My temp gauge Will not go into the normal zone it stays between the lines of the L and the beginning of the norm zone. My heat does not blow out hot air just midley warm. I changed the thermostat to an 180. Now i opened up the hood and my inlet heater core hose is not as hot as the outlet heater core hose. All my other radiator hoses are the same temp as my outlet heater core hose. What is going on i don't get it? If the outlet hose is warmer than the inlet hose what does that mean? The inlet hose goes to the bottom of the thermostat right? and the outlet goes to the water pump. Thats the way i disconnected it. A friend of mine said i need to flush my radiator with a garden hose and to refill. How will that help? Any help at all is appreciated. Thanks