Go with the newer cross flow fan if not already replaced, helps tremendously for cleaning. Also replace the wooden blocks on the front (bottom) side of the distribution augers with the new metal bearing holders. (Case has a kit for that)
Also check the rotor and pto gearboxes for fluid every week don not let those get low. Probably wouldn't be a bad idea to have them checked anyway.
If you are in real heavy crops you might look into putting the newer enclosed unloading gearbox on the 1680 if it didn't come with one already, instead of the beveled gears with shear bolts, they always caused us a great deal of trouble.
AFX rotor is a great upgrade to look into as well ( kinda pricey, but well worth it) Specialty rotor does pretty good though.
These are some things we did and we were running in wheat and corn, not ever harvested any soys or rice, but I hope this helps it's all I can think of off hand.
Good luck and God Bless
Also check the rotor and pto gearboxes for fluid every week don not let those get low. Probably wouldn't be a bad idea to have them checked anyway.
If you are in real heavy crops you might look into putting the newer enclosed unloading gearbox on the 1680 if it didn't come with one already, instead of the beveled gears with shear bolts, they always caused us a great deal of trouble.
AFX rotor is a great upgrade to look into as well ( kinda pricey, but well worth it) Specialty rotor does pretty good though.
These are some things we did and we were running in wheat and corn, not ever harvested any soys or rice, but I hope this helps it's all I can think of off hand.
Good luck and God Bless