@sd
The AC grill is in front of the radiator in FX and Mehran..stock raiator and fan dont have the capacity to cool the engine water when heat from radiator condensor is also hitting the radiator....
solution is very simple....increase the capacity of radiator to remove heat....this can be done by two methods....
1- Increase the heat transfer area of radiator by replacing the stock two channel(nali) radiator with three channel(nali) radiator.....
2- increas flow of air by replacing the stock two pole radiator fan with high speed 4 pole fan (called the double speed fan by our kabari friends)
the second option is cheaper as you mey get a new fan for around Rs. 500 from Kabari....New Radiator might cost you around Rs. 2500 and the new radiator will be of inferior quality than the original one.... i suggest that you go for double speed fan powered by relay switch for maximum speed.