my td5 starts to overheat when you are flat out but doesnt do it if its driven normally its a 1999 it has overheated before but that is due to me not cleaning the rad of the mud there is quite alot of bent fins on my rad could that be the problem i have no loss of fluids? it has become a lazy starter this week but could that be to do with the air filter i removed last weekend through getting wet my fault again snorkle wasnt properly sealed