well I know it is over heating because the antifreeze is blowing out of the over flow and the temp light didn't turn on and neither did the fan. I do clean the radiator very well after every race. I did have tape over the front bumper but I don't think that would be a problem. I let is idle for a while the yestarday and the fan didn't' come on agian but that be because it wasn't hot enough to come on cause I didn't let it idle for 13-15 min.