My GF1800 PTO doesn't want to run, when it does, may not stay running. New clutch installed, pressure checked, OK, I'm wondering if it is the one way roller clutch that puts power to the clutch pack? The PTO shaft to the mower needs some help, the quick yoke is egg shaped in the splines, causing a 1/2" out of round rotation at the rubber link (like the rag joint on the steering column in a car). I'm wondering if this vibration causes the roller clutch to disengage? Thank You!!