I am having trouble with my PTO on my Oliver Super 55 Diesel. The tractor has been in my family since it was purchased, but spent many years in and out of a barn, and probably the last 8 or so outside. When I started using it the PTO release lever was very limp when I pushed the button and let it drop into engagement. It didn"t seem like there was any thing driving it to be engaged. Needless to say, when any load was put on the PTO, it would drop out (slip). I employed a bungee cord to apply pressure for engagement for a while, until I could figure out the problem. Looked through many manuals, and could not figure out what mechanism was supposed to apply force to keep the PTO engaged. As of today, the lever has now seemed to break loose of any springforce, and floats loosely back and forth even above the stop. You can still get the PTO to engage by applying pressure back on the lever, but I am hoping someone can help me figure out what my problem it. Thanks