Hyundai Repair: 2.4l hyundai, crank sensor, balance shaft

Question
I am in the process of reassembling my daughters 2.4L after replacement of CRANK Sensor. (What a chore).  What is the mysterious cogged belt to the left going to a shaft that disappears inside the engine?  This belt is completely stripped of ALL cogs. Also, what readily available service manual will display the various timing marks you speak of in another response you provided to others?

Answer
The small belt is the rear balance shaft timing belt.  It drives one of the two balance shafts in the engine, greatly reducing engine vibration when correctly timed.  It and the timing belt last about the same amount of time.  Since one of them is stripped, it would be a good idea to replace both of them now that everything is apart.  

You can view the timing mark diagrams at www.hmaservice.com.  You'll need to register for a free account, and the site requires Internet Explorer.  

If you attempt to follow the instructions in the shop manual for timing the oil pump/front balance shaft pulley, you'll find that they ask you to remove a bolt you cannot access.  When you have the oil pump sprocket marks aligned, turn the sprocket a little one way or the other.  If it tends to return, it was set correctly.  If it tends to continue turning, you'll need to rotate it 360 degrees.