well, I recently had a general check over on the fluid in my car and noticed that my overflow bottle was down to its minimum point which i topped up. I then looked at the under the radiator cap to see if it was low on coolant as well but it seemed to be full. Prior to this i didnt notice the temp guage to be high as it seemed to be at the half way level. This was also the case after i topped up the overflow bottle after a long drive. After doing all this though i did notice that my radiator is extremely hot particulary the top hose while the bottom hose was quite cool. I may be just steptical but can my radiator be blocked in any way? I believe my overflow bottle was at its minimum due to the fact that the used the heater a few times prior to checking it, could this have caused caused it as it was to the max level beforehand. Any enlightenment would be much appreciated.