Jinma 204 Hydraulics Failure

I have a 2007 Jinma 204 with FEL.  My hydraulics totally quit.  I have isolated the problem to the pump (no oil from the pump to the Loader Control Valve and very little in the control valve itself).  I’m in the process of removing the bad pump, but am not quite sure how to proceed.  It is a single pump system, but from all the documentation I’ve ever seen, there is NOTHING on what drives the pump.  It’s not belt or electrically driven, so there has to be something coming off the motor somehow.  This is my 1^st venture into the hydraulics world, so I need to proceed cautiously, don’t like it when things jump out at you.  I pulled the adapter on
the side of the pump that the low pressure is connected to and it sprung away from the pump, so there’s a lot of tension on the whole line from the reservoir.  The low pressure line is still in the way so I can’t get the high pressure side off.  I have tried to pry the line back up to re-attach it so I can loosen the hose connection.  No luck so far.  Is there a process for eliminating all this tension?

What drives the pump?  Is there a common failure/reason for the pump failing? Is there a process for removing the pump and whatever drives it? 

Is there also a process (sequence of steps) for re-installing new pump/whatever?  How do I go about bleeding the air out of the system before re-starting the tractor?  I assume the hose connections just below the dashboard (same side as the pump) is the Diverter Valve.  Is there anything I need to do with that?

I appreciate any help whatsoever so I can get this thing back up and running with no parts left over. 

Thank You in advance!!!!!!!!!!!!