Straightening a bent PTO shaft

cathead

CATWERKS LTD
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The PTO shaft on the D4 was in neutral and I gave it a spin and discovered it had a wobble of about !/4 inch! I thought about disassembling it
but decided not to as it got bent on the machine so likely I could straighten it on the machine as well. It took all the pressure the 12 ton jack could
muster to get it straight. I started with 6 pumps on the handle.... nothing... Then went to 8 and there was some improvement. I ended up giving
it 11 pumps on the handle to get it to run true. I'm not sure what I would ever use the PTO for but it is nice to know that it is straight now and
in usable condition. Hopefully someone on HM will find this useful or at least interesting.:) P1020560.JPG

Here is a photo of the set up with the hydraulic jack conveniently sitting on the draw bar with a chisel propped underneath
for the proper angle.
 
You might want to check the rear bearing and oil seal.

I have used the principle of applying and equal and opposite force to the one which made the bend on numerous occasions. Years ago, I used to have a lot more immovable objects hiding in the grass and the lawn mowers suffered as a consequence. I was unable to use your technique in that case as the mower housing wouldn't stand up to that kind of force. I made a split bearing for the crankshaft and welded it to a 7 ft. length of I beam. I removed the crankshaft and clamped the shaft just past the point of the bend (usually at the point of the oil seal) A 6 ft. length of pipe was used bend the shaft and a dial indicator used to check the TIR. I salvaged quite a few crankshafts that way. Then I wised up and cleaned up all the rocks and iron.
 
Nice save Cathead!

i have seen PTO water pumps as well as PTO hydraulic pumps
 
You might want to check the rear bearing and oil seal.

I have used the principle of applying and equal and opposite force to the one which made the bend on numerous occasions. Years ago, I used to have a lot more immovable objects hiding in the grass and the lawn mowers suffered as a consequence. I was unable to use your technique in that case as the mower housing wouldn't stand up to that kind of force. I made a split bearing for the crankshaft and welded it to a 7 ft. length of I beam. I removed the crankshaft and clamped the shaft just past the point of the bend (usually at the point of the oil seal) A 6 ft. length of pipe was used bend the shaft and a dial indicator used to check the TIR. I salvaged quite a few crankshafts that way. Then I wised up and cleaned up all the rocks and iron.

Yes, it would be a good thing to disassemble and inspect it and even run it a bit and check for any leaks.
 
Good fix Cat- that bottle jack looks like it's done about a zillion and one repairs and probably will do a zillion more
Don't ever clean and paint it it will promptly break
Mark
 
Anytime I managed to bend any shaft there was always some damage to a ball bearing. If it is a roller bearing or a bushing then it is less likely to get damaged, ball bearings are the most easily damaged from an impact or great force. Some times if it is not used a lot and not a precision application the bearing will still live a nice long life even with a bit of damage.
 
Good fix Cat- that bottle jack looks like it's done about a zillion and one repairs and probably will do a zillion more
Don't ever clean and paint it it will promptly break
Mark


It was an old jack when I got it back in about 1966 or so and has never failed to work in all those years. I don't remember ever
changing the oil in it or adding any oil for that matter. I did clean and paint it green about 25 years ago. :)
 
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