New forum member here but longtime member elsewhere.
I own a 2015 M9960 ROPS 12 speed, used exclusively for mowing. Currently, I use a HD 7' mounted cutter but plan to replace this cutter with a 12 or 15 foot BW cutter within the next year. My tractor has about 46 hours on the meter.
Recently, I was at my local CNH/Kubota dealer, where I am a good customer and on first name basis with everyone there. I noticed an M9540 in the shop that was split for repair work. Upon inspection, I noticed catastrophic failure of the PTO brake. Being both lifetime mechanic and design engineer, I didn't like what I saw so I researched to see if the PTO brake in my M9960 was the same.
I learned that the PTO brake problem was a known issue and the entire PTO clutch/brake assembly had been redesigned during the M9960 model run. The new unit is more robust and may solve the issue. I say may because I viewed the replacement unit before the M9540 was reassembled, and, being a design engineer, remain skeptical. Further research, of course, revealed that my M9960 was built before the engineering change to the new, more robust design was put into production. None of you folks know me, but experience has taught me that I am not a so-called "lucky" person.
The issue in question involves dissipating the energy in a rotating PTO load once the PTO is turned off, which applies the PTO brake. The old PTO brake design (and, maybe the new design) is inadequate to do so, under conditions expected to be encountered in normal operation by most users. Such loads include rotary cutters.
Being both a mechanic and design engineer, I would never turn off the PTO with a connected inertial load without first reducing the engine RPM to idle. Indeed, I idle the engine and back the mower into uncut grass immediately upon turning the PTO off. That said, I can find no such instructions in my M9960 owners manual.
More troubling is the fact that the M9540 that I inspected had spent it's entire life operating a hydraulically driven boom mower. In this situation, the PTO drives only a high capacity hydraulic pump. There is little or no inertial load, yet this PTO brake failed catastrophically.
Of course, this M9540 was out of warranty on both elapsed time and, maybe, hours. IIRC, it had somewhere around 2,000 hours on the meter.
I was told by my dealer that Kubota paid none of the repair bill for this unit, even though the problem was a well known issue as evidenced by the redesign. I was told that the repair bill was around $3,500, nearly $1,000 of which was the cost of the replacement, redesigned PTO clutch/brake assembly.
I'm sold on Kubota, folks, but this troubles me, especially because I own a 46 hour M9960 with the old design PTO clutch/brake that will be long out of elapsed time warranty long before any such failure may occur.
Does anyone have additional information regarding this issue?
Thanks, in advance.
SDT
I own a 2015 M9960 ROPS 12 speed, used exclusively for mowing. Currently, I use a HD 7' mounted cutter but plan to replace this cutter with a 12 or 15 foot BW cutter within the next year. My tractor has about 46 hours on the meter.
Recently, I was at my local CNH/Kubota dealer, where I am a good customer and on first name basis with everyone there. I noticed an M9540 in the shop that was split for repair work. Upon inspection, I noticed catastrophic failure of the PTO brake. Being both lifetime mechanic and design engineer, I didn't like what I saw so I researched to see if the PTO brake in my M9960 was the same.
I learned that the PTO brake problem was a known issue and the entire PTO clutch/brake assembly had been redesigned during the M9960 model run. The new unit is more robust and may solve the issue. I say may because I viewed the replacement unit before the M9540 was reassembled, and, being a design engineer, remain skeptical. Further research, of course, revealed that my M9960 was built before the engineering change to the new, more robust design was put into production. None of you folks know me, but experience has taught me that I am not a so-called "lucky" person.
The issue in question involves dissipating the energy in a rotating PTO load once the PTO is turned off, which applies the PTO brake. The old PTO brake design (and, maybe the new design) is inadequate to do so, under conditions expected to be encountered in normal operation by most users. Such loads include rotary cutters.
Being both a mechanic and design engineer, I would never turn off the PTO with a connected inertial load without first reducing the engine RPM to idle. Indeed, I idle the engine and back the mower into uncut grass immediately upon turning the PTO off. That said, I can find no such instructions in my M9960 owners manual.
More troubling is the fact that the M9540 that I inspected had spent it's entire life operating a hydraulically driven boom mower. In this situation, the PTO drives only a high capacity hydraulic pump. There is little or no inertial load, yet this PTO brake failed catastrophically.
Of course, this M9540 was out of warranty on both elapsed time and, maybe, hours. IIRC, it had somewhere around 2,000 hours on the meter.
I was told by my dealer that Kubota paid none of the repair bill for this unit, even though the problem was a well known issue as evidenced by the redesign. I was told that the repair bill was around $3,500, nearly $1,000 of which was the cost of the replacement, redesigned PTO clutch/brake assembly.
I'm sold on Kubota, folks, but this troubles me, especially because I own a 46 hour M9960 with the old design PTO clutch/brake that will be long out of elapsed time warranty long before any such failure may occur.
Does anyone have additional information regarding this issue?
Thanks, in advance.
SDT
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