Tractor Repair: case 2590 power surge on clutch release, clutch pack, clutch release

Question
Hi Arnie,
I have a 70's model? Case 2590 that surges to the point that the front wheels come off of the ground no matter how lightly and slowly you release the clutch.  Do you have any ideas on what is causing this?  I don't know if this is clutch related, injection pump related, throttle governor related, etc.  Thanks for any help you can offer.

Russell

Answer
  I will assume that this is a powershift transmission.  Make sure the clutch pedal, cable, and linkage on the powershift control valve are working smoothly and are adjusted properly with no loose hardware.  It can also be caused by a bad modulating spool or sticking pilot spools in the control valve, or an internal leak in the C2 clutch pack or sticking C2 clutch piston.