Tractor Repair: 1086 PTO wont drive, input shaft, output shaft

Question
Hi Arnie, one of our 1086's has a problem with PTO. The PTO started running continuously during use one day and wouldn't stop so we pulled it apart and serviced PTO valve, replaced all seals o-rings etc, reinstalled housing, part filled trans with oil, checked that input shaft was turning with motor running, topped up with oil and now it won't turn either output shaft at all. So pulled it out again, rechecked valve, reinstalled checking there was still drive from input shaft but still nothing moved on either output shaft - any ideas? Everything else on tractor is working fine that we are aware of but havn't specifically checked anything else because thought the PTO is pretty a self contained unit other than drive from input shaft? Thanks for any assistance - Rob.

Answer
Hello,

  It sounds like you have more than one problem.  The pto running continuously is usually because of pto clutch plates warped or stuck together, bad pto brake, or something stuck in the control valve.  The pto not running at all is usually from a suction leak on the oil pickup tube or a sheared pin in the control valve spool.  The pickup tube is held on with a clamp that sometimes allows the tube to move and pull out of the seal in the pto housing.  We usually braze the tube to the clamp so it cant't move.  The control valve spool is a 2 piece design held together with a very tiny pin that sometimes breaks and then the pto won't work at all.  You should not be able to pull the control spool out from the top, it must be removed from the bottom plug which requires removal of the pto.  If you can pull half of the spool out from the top, then the pin is broken.