No, but if you remove the top one, which I believe is the return from the heated core, with the engine running, you can pull it off, and make sure there is not an air lock in the heater. My trucks heater was luke warm until I back flushed it with the garden hose gently several times. I could not believe the crud that came out. Now, it works like a champ. After hooking it back up, I flushed the block, and rad, then filled with warm water and a cup and a half of calgon. Ran it for a half hour with no thermo, flushed it out, put in the green stuff.
Christopher.
Calgon!, take me away!
