My 95 Zetec is still overheating. If I run the AC it just runs hot (L to edge of red), if i run without AC on it runs full red. I put a 180 thermostat in it, flushed the cooling system and put in new orange coolant and it made no difference. The fan appears to be doing it's thing so now I'm down to either a clogged radiator or bad water pump. Do the Zetecs have impeller issues like the Duretecs ? Is there anything I'm overlooking ?