BleedingOrange
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At what RPM is it best to engage the PTO ?
Is it the same for the rear and mid PTO ?
BX25
- Thread starter JonCbx25guy
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Is it the same for the rear and mid PTO ?
OP
JonCbx25guy
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Fluid was fine. PTO was engaged and in use. I was running about 2500 rpm when it grenaded. PTO had plenty of play. 180 hours on the unit.
s219
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Looking at the parts diagram, that circular bulge on the case where the crack appears is the end-bearing for the gear shaft that runs from the transmission and turns opposite the direction of the PTO shaft. A small gear on the gear shaft engages a large gear on the PTO shaft. Based on the gear sizing, the gear shaft would be spinning 2-3X faster than the PTO shaft with 2-3X less torque.
Based on the gearing and the direction of rotation, am thinking that if the PTO shaft suddenly stopped rotating or got shocked bad, the end bearing on the gear shaft is going to want to walk the way it's shown in that crack, as the suddenly stopped PTO shaft sends a reaction back to the gear shaft, it's bearings, and upstream parts.
I suspect the case, gear shaft, bearings, and possible connected gears/shafts will need to be replaced. That's a pretty serious repair.
Would be good to know what implements you have been running, and if they have proper shear bolts. Clearly, something did not give in the implement or the shaft / shear bolts when an obstacle was encountered, and the shock/load went upstream into the transmission case. I believe this could also be caused by engaging the PTO at a high speed if the implement on the other end had a large flywheel mass to spin up (like a wood chipper for instance).
It's very likely the damage occurred prior to the catastrophic failure when you noticed it. Perhaps sometime in the past (certainly before you heard clicking this time), a load or shock was applied to the PTO, and it started you down on the path to full failure.
If it was a manufacturing defect, there would be an obvious fracture on a shaft/gear inside the case that looked older or shiny (due to rubbing), or was tied to a void or casting defect in the metal. But I'd think that would have shown up earlier than 180 hours. So my bet is that something overloaded or shocked the PTO system in recent use.
Based on the gearing and the direction of rotation, am thinking that if the PTO shaft suddenly stopped rotating or got shocked bad, the end bearing on the gear shaft is going to want to walk the way it's shown in that crack, as the suddenly stopped PTO shaft sends a reaction back to the gear shaft, it's bearings, and upstream parts.
I suspect the case, gear shaft, bearings, and possible connected gears/shafts will need to be replaced. That's a pretty serious repair.
Would be good to know what implements you have been running, and if they have proper shear bolts. Clearly, something did not give in the implement or the shaft / shear bolts when an obstacle was encountered, and the shock/load went upstream into the transmission case. I believe this could also be caused by engaging the PTO at a high speed if the implement on the other end had a large flywheel mass to spin up (like a wood chipper for instance).
It's very likely the damage occurred prior to the catastrophic failure when you noticed it. Perhaps sometime in the past (certainly before you heard clicking this time), a load or shock was applied to the PTO, and it started you down on the path to full failure.
If it was a manufacturing defect, there would be an obvious fracture on a shaft/gear inside the case that looked older or shiny (due to rubbing), or was tied to a void or casting defect in the metal. But I'd think that would have shown up earlier than 180 hours. So my bet is that something overloaded or shocked the PTO system in recent use.
OP
JonCbx25guy
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- Kubota BX25
Thanks for the information. I did retrieve the tractor today and will have more pics. Case is fine except for a locating pin on the left side? Gear is missing a tooth on the small gear that drives the main PTO gear. As far as the implement, it was a Woods TSG 50 and it was about stump fifty over a year or so. Maybe the clutch was frozen on the unit........heck of a way to find out! The breakaway PTO gear!
Code54
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Sorry to hear about the bad luck on that one. Interested in seeing what you learn as you go and finding what cause the gear to break a tooth. Im thinking the clutch as you stated - that is a lot of weight spinning back there. That TSG50 is a NICE stump grinder. How does it "normally" do on the BX?
OP
JonCbx25guy
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Dropped off the tractor today. Definitely not good. New case required. Estimate soon. I will definitely will be adjusting my slip clutches to be REALLY loose now! Thanks for the information and help on here......
