never really had that problem unless! May need new brush on the rotary air screen. the bottom drain plug could be missing on the air plenum or sealer around door is leaking. check for air leaks good.
Check above the rotating air screen just below the top of the machine. There is a slot opening that is allowing dirty air into it. I discovered this opening when soybeans were inside by the raditor. I placed duct tape over that opening. JWK
As I understand your comment Nate,the plugging occurs because the fins on the oil cooler portion of the radiator are much closer spaced then the fins of the engine radiator. My 1460 is the same way and have wondered if the wider spaced oil coller fins were ever made.Will check the next time i get to the local parts yard.