2006 yz450 overheats

I have a 2006 yz450 that keeps pressurizing the cooling system. I just sent the head off and had it rebuilt I would assume that the shop who rebuilt the head would have checked for cracks and so forth. I installed the head and still have my cooling system getting pressurized, I'm starting to think I need to have the cylinder checked, I have replaced all o rings and seals in the Cooling system along with the radiator cap. Im also wonder if it's possible that the head bolts have been over torqued and stretched? I'm at my wits end trying to track this down. I have put a pressure tester on the system and confirmed that it for sure has a leak I just don't know where??!!

Heating the coolant pressurizes the cooling system under normal conditions. Let's assume you knew that and that you're talking about an abnormal level of pressure. You can have the system tested for the presence of combustion gases, which definitively indicates a combustion leak into the cooling system, or rules it out.

How did you do the head torque?

http://www.thumpertalk.com/forum/showthread.php?t=972816

Heating the coolant pressurizes the cooling system under normal conditions. Let's assume you knew that and that you're talking about an abnormal level of pressure. You can have the system tested for the presence of combustion gases, which definitively indicates a combustion leak into the cooling system, or rules it out.

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How did you do the head torque?

http://www.thumpertalk.com/forum/showthread.php?t=972816

Lol yeah I'm referring to an abnormal pressure. It pressurizes enough to fill my overflow bottle and puke it out the overflow. Please keep in mind this engine is in a quad. If you look at one of my previous post I have a picture of the head you can tell it got pretty damn hot. I sent the head off had it checked, new valves installed and so forth. I didn't resurface the cylinder and I think that's the issue. Head was torqued just like you said in that post.

In that case, the next most likely thing is that the head and/or the cylinder deck isn't flat enough, whether it was "checked" or not. Everything else sounds correct, the way it's written up.

Has the cylinder been checked for cracks/flatness?

Have you verified that the water pump is turning?

I had the actual head checked and surfaced while it was being serviced. I'm really debating on buying a new cylinder, or havin the one on it surfaced?

Also I'll double check the water pump impeller when I drain the coolant again

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