I have a 1995 F-150 V-8 5.4 and noticed some steam in the cab a few weeks back, so I changed out the heater core. Only problem, when I started it back up and topped coolant after getting up to temp, then it wanted to overflow. No heat coming out of the heater either, with the outlet hose running to WP not getting warm.

Is there something I did in the install that could have caused this or is it just air in the heater core having to work it's way out? All of the online tutorials and pictures show a vacuum hose on the top of the heater core cover that has to be disconnected and mine did not look like any in the pictures. How do I get the air to cycle out of the heater core?

Thanks,

Tom

 

Turn the temp to full hot on the heat control. If you have ramps park thr truck on them with the nose uphill, then go through the burp/fill process as before. The heater gets the coolant after the head and sometimes they get air locked when trying to refill.

 

Thanks for the tip, I have done this twice, how many times until you know all the air is out? I have been able to squeeze some bubbles out of the big hose going to the radiator from the block, until it gets too hot and the radiator is gurgling and burping. I have read that you can pull the outlet hose off where it goes into the water pump, would this be a good way to get the air out of the heater core?