Well one of two things is happening with my truck either the thermostat is stuck that was brand new or the radiator is clogged... Radiator is a newer champion radiator... I highly doubt it's the brand new water pump but it could be...
The top hose goes under pressure quickly and gets hot, and the bottom hose is damn near Stone Cold... Bottom half of the radiator is cold or not hot... I did drill a pinhole in the thermostat I'm pretty sure of that... I need to pull the intake manifold off anyways to seal the back I don't know how that leaked I've never had that happen.. again lots of Right stuff extra in the corners I've done this dozens of times and never had one leak on me...