I recently reinstalled my engine, trying to fill up the coolant, read tons of threads on how to do it, I have the bleeder screw open, i'm pooring coolant into the reservior, and it won't leave the reservior. Engine off, engine on, it won't go in. I know the system was empty, the whole front end was taken apart, but it won't take any coolant. What the heck?

 

did you try massaging the radiator hoses? That's how I got mine to take it in