Tractor Repair: New Holland 258 Baler, drive sprocket, crank arm

Question
While baling hay I broke the shear pin. The baler now seems to be out of time. How do I time it

Answer
Hello,
     Do you possibly mean a 268?  There is no 258 baler.
  Which shear pin, the flywheel or the knotter shear pin?  There are timing marks on the knotter clutch and drive sprocket, and on the front by the crank arm of the gearbox.  But the most accurate way is to time the needles to the plunger and ignore the timing marks.  Trip the knotter clutch and turn the flywheel in the normal direction of rotation until the needles start to move, and stop turning when the tips of the needles are just starting to enter the bottom of the bale chamber.  The tips on the face of the plunger should be about even with the tips of the needles, to no more than 3/4" behind the tips of the needles.  If the tips on the plunger are more than 3/4" past the tips of the needles ( toward the rear of the baler ) the timing is too late.  If the tips of the needles come up before the plunger gets back that far, the timing is too early.  If it needs to be changed, turn the flywheel backward a turn, and put the needles back in their home position. Loosen the knotter drive chain and jump the knotter drive sprocket on the chain clockwise to retard the timing, and counter-clockwise to advance the timing.  Tighten the chain, turn the flywheel in the normal direction again and bring the needle tips back up to the chamber again to recheck.  Repeat these steps and keep rechecking until you get it correct.  DO NOT DISABLE THE PLUNGER SAFETY STOP OR YOU CAN BREAK THE NEEDLES OFF!  If the safety stop is hitting and shearing the flywheel pin, it's doing it's job to protect the needles.
                             Arnie