P1150 after engine replacement, but not before. Air pocket?

Went to take the new ride on it's maiden journey with the new engine last night so I could have it inspected to get the tags @ DMV today. Warmed it up a few minutes in the shop, & as I pull out it sets a check engine and maint. req'd light. Scanned a P1150 code. If I let the car set a while, I can jumper on the electric pump via the relay socket, & it sounds loaded and quiet as it should, I can hear some gurgling when it stops. If I run the engine a minute, then jumpering the pump, it sounds loud and unloaded, occasionally catches a gulp of water & back to dry. If I run the engine a bit it gets hot quickly but the radiator hoses are cold. (new mech water pump) I'm pulling my hair out, seems like it has trapped air to my thinking, but for the life of me I can not coax it out. Tried the bleeder, tried squeezing hoses, tried pulling a vacuum, tried jacking up alternate sides of the car, running it with rad cap off/bleeder open.......am I chasing my tail on this?

 

I just tried it, no gurgling and no noticeably warm air. one question, should i have instant heat with the heated tank, or does it need to run a while? I gave it about 3 minutes, dont want to get the engine too hot.

 

Ok, I will give that a try

 

Getting better, finally got cabin heat to come through after about 12 minutes, rad hoses still cold, but now the upper one is empty so the air has moved. Good stuff, thanks.

 

Ok, thanks again, still working on bleeding, but I've gotten almost another gallon in it now. The CHRS pump sounds completely dry right now, but the engine is hovering around 190*, I have coolant flow in the rad now, fan comes on. Is there some kind of check valve in the rad bleeder? I try to crack it with light pressure in the rad to burp it and nothing comes out. I would expect it to push coolant or relieve air and let off the system pressure. Mityvac pulls little coolant bubbles out so it shouldn't be plugged.

 

I did look at the link last night. I still never did get fluid to come out of the bleed, I think it was pulling air around the bleed screw, It seems to have stopped taking coolant now. I think I might have been wrong on the pump, I never really got to hear it before, & I think what I was hearing before as "loaded" was it deadheading on that big air blob I had. Sounds like there is fluid moving around with it on. I haven't driven the car yet, but so far all seems ready. Going to give this thing a big shampoo job inside before I go out, (previous owner had young children) what a mess they can make!