I have just replace a water pump seal on my 2014 RZR 4 800. I tried to refill the radiator with new coolant and unscrew the vent screw next to the motor with the front raised up, I cannot get any radiator fluid to come out of that breather hole! Could it possibly be a stuck thermostat? If anybody has an idea what it could possibly be any suggestions would be greatly appreciated! Please watch video to understand a little bit more of what I’m talking about!