Tractor Repair: 1948 McCormick Deering, fan belt loose, mccormick deering, fan pulley

Question
Hi, I'm asking this question for my father-in-law. He has a 1948 McCormick Deering Standard Orchard (he says mdel is 04 and series is OBH). His old belt dissintegrated when he started it last time so he put on a new belt (the part number was still legible on the old belt for cross referencing). After putting it on the tractor started overheating. He says it has a split shev and can see a screw head and a bolt head. He's not sure which one is the adjuster for it. I tried looking this up myself and read that there should be a locking nut on the adjuster. What steps should he take to tighten his belt? Which one is the adjuster for the belt? Thanks for your input. M~

Answer
  The fan pulley is a 2 piece design and has threads on the center hub, so you can screw the halves closer together making the pulley narrower which tightens the belt.  The front half of the pulley has a lock screw and jam nut that lock it in position.  Loosen the jam nut and back out the lock screw, then while holding the rear half of the pulley from turning, turn the front half to make the pulley narrower until the belt is tight enough.  Align the lock screw with one of the notches in the center of the pulley, and tighten the lock screw into the notch.  Then tighten the jam nut to keep the lock screw from coming loose.  I'm not sure what bolt head he is seeing, there is only the lock screw with a jam nut on the pulley.  The front part of the pulley is usually hard to turn because it gets rusted in place.  It helps to spray some penetrating oil into the notches of the pulley and tap on it with a hammer and long punch until it can be turned easily.  Not sure how he even got the new belt on.  You have to turn the front half of the pulley to make the pulley as wide as possible to get the belt on, and then turn it the other way to tighten the belt.