In Reply to: Knocking in Hydrolic Pump Area posted by Charles (N.C.) on October 02, 2017 at 10:20:26:
The hydraulic pump pistons are operated by cams and cam blocks that the PTO shaft passes thru. When new, the PTO shaft turns the cams, and push the pistons in and out, without making noise. As those cams and cam blocks wear, more and more clearance means they start knocking. They can knock pretty loud under load for a long time and still work just fine.