MF 1135 PTO Engages on it's Own

[Speedyzee]

Hello; first time here; I didn't see any posts on this topic so here goes. Recently bought a MF 1135 for running a snowblower at my automotive shop after the nightmare we had last year trying to get the landlord to keep the yard clear. Runs well, paid 2 grand for it (that seem decent?) I've worked as a mechanic and millwright for years so I'm mechanically inclined and have this issue - shortly (approx 3-5 seconds) after startup there is a definite sound of something hydraulic coming up to pressure - nothing excessive, but noticeable (is this normal?) Every few times it happens, the PTO will engage. Other times it will engage after the tractor has been running for a while. Once engaged you have to shut off the tractor and restart it to have the PTO disengage. I've read cases where warped clutch plates will cause a PTO to spin, but this one can sit motionless for half an hour and then suddenly spin up so I suspect a hydraulic control issue? We did try a 2x4 across the top of the shaft to the 3 point and I can't stop it from turning with friction - it seems to be totally engaged. I changed the hydraulic filter in front of the rad and freshened up the fluid (looks clean) Everything else seems to work (3 point, steering and remotes). I've got a manual on order - anyone have any suggestions where to start looking for the problem? Thanks in advance for any help.

 

[Dieseltech]

The hydraulic system startup at about 5 seconds is normal. The PTO shift valve on the dash controls oil to apply the PTO clutch, and when in off position most 1100 series tractors will creep slowly. Have never seen one act like yours does, warped clutch plates would cause it to spin all the time like you said. Seldom see the PTO clutch fail. Did have an 1105 fail due too not enough shimms on the rear shaft, drum was drifting back far enough to leak oil pressure to leak off, burning the clutch plates.