Oil Pump

Drain the engine oil.
Remove the drive belts.
Turn the crankshaft pulley, and align its groove with timing mark "T" of the timing belt cover.
Remove the timing belt. (Refer to TIMING BELT )
Remove the timing belt tensioner (A).

Fig 1: Identifying Timing Belt Tensioner
Courtesy of KIA MOTORS AMERICA, INC.
Remove the oil pan and oil screen.
Remove the alternator. (Refer to ALTERNATOR )
Remove the air conditioner compressor tensioner bracket (A).

Fig 2: Identifying Air Conditioner Compressor Tensioner Bracket
Courtesy of KIA MOTORS AMERICA, INC.
Remove the front case.
1. Remove the screw from the pump housing, then separate the housing and cover (A).
  
  Fig 3: Identifying Housing And Cover With Screw
  Courtesy of KIA MOTORS AMERICA, INC.
2. Remove the inner rotor (A) and outer rotor (B).
  
  Fig 4: Identifying Inner Rotor And Outer Rotor
  Courtesy of KIA MOTORS AMERICA, INC.