I'm hoping you can help. I picked up a 1997 sullair diesel towable compressor at auction.  It was not running when I got it.  I finally got it running after a new injection pump.  While it's running it won't produce any air.  The tank has fluid. I even pull the pressure release on the side of the separator tank while it's running and nothing.  I've tried manually opening the intake valve and it didn't change anything.  I even thought there might be a problem with the hydraulic thermostat and bypassed that and that didn't change anything. Is there anything else I can do/test before I tear into the pump?  It seems like l the small air lines are hooked up properly.  Also I've been running it at idle mostly.  I did go full throttle with it a few times and still no air. Any help would be appreciated.  Thanks