2003 Jeep Liberty

Dear sirs, I have a 2003 Jeep Liberty, V6, 3, 7L gasoline engine, htis vehicle gives me problem of overheating. I have changed the radiotor fan, hot sensor, three times the fan motor relay, also the radiator has been renewed. The question: what could be the reason for overheating? If you did not install the orginal fan motor relay could that be the problem? Can you give me a complete breakdown of the electrical circuit for the control the engine temperature as well the stearing of the relay etc? My email address is: karel. Vis @setarnet. Aw Thanks and my regards. P.S. I am willing to give a donation after receive the answer and also send me your information for the donation!
Karel Vis
November 1, 2012.

Have pressure checked for head/intake gasket bein blown.

Nov 1, 2012.