a tad dangerous hooking up. but if you could attach to rear of tractor, and raise up the 3pt hitch just enough to get shaft connected. and then let it run for a bit to warm things up. then raising up / lowering the 3pt hitch "not a lot" but to create some push/pull force on the shaft as it is spinning.
have had to do this to the post hole digger over the years. it seats for a couple years plus, then time to come use it, it rusted up some. thankfully i can easily remove the auger bit, and just have the gear box on the end. and it shakes and rattles some. (not real smart idea) gear box darn near flips on me, and cause additional damage. but it frees up the pto shaft, enough to get some grease on it, and then away she goes freely.
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go with other folks notes. just random blah here.
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just wondering if you could some how attach an impact wrench to end of PTO shaft. so you could obtain clock wise and counter clock wise sudden burst of shock vibration. that an impact wrench creates.
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what i am trying to get at... when dry fitting sch40 fittings say 2", 3", 4" fittings. oh the pipe will slide all the way in. but you are out of a lot of luck getting the pipe back out to prime and glue/solvent weld everything together. i end up taking a screw driver and hammer. and going around tapping the fitting end, right up against the pipe. and kinda walk the fitting off the pipe. (kinda like walking a dresser on a couple legs to position it)
if you had say a log splitter, and some how able to hook 2 ends of shaft to it. see if you could pull on it some. rotate shaft some, give it another pull, rotate some give it another pull.
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with other folks idea, of warming it up...
take 2 to 4 garbage bags and a roll of tape. and stick end of shaft into garbage bag, then toss a couple more on. then use tape to loose hold bag around shaft, and start dumping in boiling water. the tape is there to reduce amount of hot water you need to dump in.
if you could find a kitchen sink to garden hose adapter ((most likely in aquariums / fish isle of some local store possibly)) turn sink to hot. and run garden hose out. to fill up container / garbage bag. menards/lowes/homedepot most likely have sink to garden hose adapter in the "misc brass fitting section" were all the little baggies are of different fittings.
