450 running hot

[RMAC]

I have a straight 450 and the temp runs in the red a lot, the motor was rebuilt 2 years ago, so I don't no if this is a result of the break in period, (I've only put about 25 hours on it). I put a lower temp setting t -stat to see if that helps, and a new cap, but it still runs hot. Also when I fill the radiator I loose a good amount of coolant out the overflow. Does anyone know what the problem may be? I'm thinking maybe I need a new radiator

[jtrichard]

try washing the dirt out of the fins they can get plugged or the rad. is plugged inside.... those would be my guess

[RMAC]

Turns out it was the radiator cap, that was causing the problem