Alright so my 90 xj 4.0 is randomly bogging down and stalling out on start up this does not happen all the time and only on start up also my belt screeches when it bogs down my theory is I have a pulley going out some where any suggestions?

 

Check the water pump, alternator, A/C compressor, power steering pump, mechanical fan pulley, and belt adjustment pulley to see if they are seizing or have bad bearings. Pull the belt off and spin each one by hand, feel for any rough rotation and listen for clicking and grinding noise.

 

Got ya I've ruled out alternator as its only a month old however mech fan has a plastic bag around the shaft where po carelessly placed it it was caught by blades