Bx2816 snowblower with bx2811 quick attach eating coupler

[440lonnie]

Hi everyone,
I have had my bx23s since 2018 and bought it with the quick attach and the front mount blower.
Recently I pulled off the inspection cover and noticed the coupler listed as male automatic clutch shaft part number 77700-04150 is being eaten away by the other side of the coupler although it doesn’t show as aggressive wear on the other side.
I might have 30 hours total on the blower assembly which seems pretty pre mature wear to me. The 2 couplers do seem to mesh together properly as the wear goes all the way to the bottom of the coupler.
Is this normal wear that needs to be addressed every couple of years?

 

[GreensvilleJay]

have the tractor but not the blower
but...

I'm assuming you use the PTO lever to control power to the snowblower augers ?. then that kind of wear may be caused by a LOT of 'engage-disengage' operations.

hmm, wonder if it's an 'alignment' issue ? Though I suspect taht shouldn't be possible ??

That 'coupler' looks like a 'Lovejoy' but missing the critically important 'rubber' middle piece.

Sure hope those that have the quick connect system will reply. I'm curious about it. Heck 30 hrs is like 3 days use for me....,when it snows.

 

[Stew]

what RPM are you engaging the PTO at?

 

[440lonnie]

what RPM are you engaging the PTO at?

I generally keep the R's down when i engage but i think i will start engaging at idle then ramp up once it is running.
It seems more of an alignment issue as if they are meshing off angle but the k connect center hub floats so there is nothing that could be adjusted with that

 

[440lonnie]

OK so i think i have it figured out. there are 2 holes on the female clutch shaft that i thought held set screws. so i pulled out my Allen key set to see if i could loosen them so i could change the position of the clutch and it went right through.
turns out there is a bolt missing that i dont believe was ever installed right from when this was new.
with the bolt missing it allowed the female clutch shaft to walk freely back and forth on the main drive shaft that goes into the blower causing the gears to mesh in different spots as the clutch slides back and forth.
I felt there is no way this could be considered normal wear and tear on an attachment with probably less then 30 hours on it.

 

[440lonnie]

OK so i think i have it figured out. there are 2 holes on the female clutch shaft that i thought held set screws. so i pulled out my Allen key set to see if i could loosen them so i could change the position of the clutch and it went right through.
turns out there is a bolt missing that i dont believe was ever installed right from when this was new.
with the bolt missing it allowed the female clutch shaft to walk freely back and forth on the main drive shaft that goes into the blower causing the gears to mesh in different spots as the clutch slides back and forth.
I felt there is no way this could be considered normal wear and tear on an attachment with probably less then 30 hours on it.

 

[DustyRusty]

The bolt was there when you purchased the snowblower, but for some unknown reason the bolt will break and the part will walk back and forth until you install a new bolt. So far I have gone through 2 bolts in one year. I have addressed this a number of times when others have asked about that part wearing out. I have an idea of how to prevent it from happening, but I will not let it out until I try it this spring. When you get your new parts, make sure to keep an eye on the bolts to make sure that they haven't broken and fallen out.

 

[440lonnie]

The bolt was there when you purchased the snowblower, but for some unknown reason the bolt will break and the part will walk back and forth until you install a new bolt. So far I have gone through 2 bolts in one year. I have addressed this a number of times when others have asked about that part wearing out. I have an idea of how to prevent it from happening, but I will not let it out until I try it this spring. When you get your new parts, make sure to keep an eye on the bolts to make sure that they haven't broken and fallen out.

I would have expected that the paint would show signs of marring or the edges chipped where the fastener was tightened down if the bolt was installed from new.
The keyway is still intact so the only way a bolt could have broken is if a large impact was transferred from the drive shaft coming into the blower towards the driveshaft but the driveshaft going to the coupler has a slip joint.
Either way this is something that should be added to regular inspection list for people who own this setup as the 2 replacement clutch parts are up around 550 mark.

 

[Akpj]

I had the same issue with my setup…LX2610 with the 2980 blower. After replacing the parts ($$$!!) I had two grade 5 bolts (which is what the manual calls for) break. I’ve since installed a grade 8 bolt and haven’t had a breakage in over 20 hours of use. I still inspect prior, during and after use… takes about 2.5 hours to clear my road after a decent snowfall.

 

[440lonnie]

I had the same issue with my setup…LX2610 with the 2980 blower. After replacing the parts ($$$!!) I had two grade 5 bolts (which is what the manual calls for) break. I’ve since installed a grade 8 bolt and haven’t had a breakage in over 20 hours of use. I still inspect prior, during and after use… takes about 2.5 hours to clear my road after a decent snowfall.

Ok I will upgrade the bolt then for sure thanks!

 

[DustyRusty]

I may be wrong, but I believe that the reason that Kubota uses a grade 5 bolt, is that they want it to be sacrificial and break should the gears not mesh properly. This is the only reason that I haven't gone to a grade 8 bolt. I do keep a constant vigil on the bolt. I am contemplating making a ring that will go behind the coupling will keep it from moving in the future. I can't believe that Kubota isn't aware of this problem with the K Connect and hasn't issued a service bulletin with some form of resolution to the problem. I just posted my conclusions about why the bolt is breaking and how to prevent it from breaking in the future. Please vote in the poll so we can see how many of our snowblower members have been affected by this issue.

Kubota K Connect Snowblower problems explained.

 

[Akpj]

I may be wrong, but I believe that the reason that Kubota uses a grade 5 bolt, is that they want it to be sacrificial and break should the gears not mesh properly. This is the only reason that I haven't gone to a grade 8 bolt. I do keep a constant vigil on the bolt. I am contemplating making a ring that will go behind the coupling will keep it from moving in the future. I can't believe that Kubota isn't aware of this problem with the K Connect and hasn't issued a service bulletin with some form of resolution to the problem. I just posted my conclusions about why the bolt is breaking and how to prevent it from breaking in the future. Please vote in the poll so we can see how many of our snowblower members have been affected by this issue.

Kubota K Connect Snowblower problems explained.

Thanks for the investigation on your part. I do have to say that i do raise the blower up more than an inch when reversing. Ill be pulling the plate to see what occurs when i raise the blower. I always engage/disengage blower at idle, and after servicing always rotate the augers by hand to engage the couplings before starting tractor.

 

[GreensvilleJay]

curious...
if the clutch end is splined onto the shaft, then the 'missing' bolt is only used to keep it in the proper position on the spined drive shaft. Torque (force) gets transmitted through the splines not the bolt, so HOW can that bolt break ? I can see the nut, if not a high quality self locking nut, vibrate undone, but not 'sheared off'.

 

[DustyRusty]

curious...
if the clutch end is splined onto the shaft, then the 'missing' bolt is only used to keep it in the proper position on the spined drive shaft. Torque (force) gets transmitted through the splines not the bolt, so HOW can that bolt break ? I can see the nut, if not a high quality self locking nut, vibrate undone, but not 'sheared off'.

The shaft is a round shaft with a keyway cut into it. The coupling has a matching keyway and both the coupling and shaft are drilled for a bolt. When there is pressure on the coupling pushing it rearward when the snowblower is lifted to its fullest height, the bolt is stressed in one direction. When the snowblower is lowered, the couplings are then pulled together tightly by the mating ears on the 2 couplings, causing the bolt to be stressed in the opposite direction. Do this enough times, and the bolt fails and the parts start to slide around causing the wear. I haven't experienced the damage to the couplings yet, but I have experienced the loss of 2 bolts. The first one was when I purchased the snowblower used and noticed that it was missing, and the second time was last spring when I remove the snowblower and found the replacement bolt missing. I didn't give much thought to this as being a problem until others on the forums started reporting the worn-out couplings. That is when I put 2 and 2 together and got 22 (joke). Today I verified the cause when I removed the cover plate on the K Connect and observed the relationship between the two couplings in the lowered position and the elevated position. I am mulling over a modification of a steel spacer ring behind the coupling on the snowblower that will prevent the coupling from moving rearward eliminating the possibility of a broken bolt in the future, and a rubber bumper on the K Connect itself that will prevent the snowblower from being lifted much more than an inch and a half. That will take some time to do the measurements and calculations of how to properly do this without damage to the snowblower, consequently, this will become a summer project.

 

[GreensvilleJay]

In another thread, similar issue, someone posted that the blower is solid to the kconnect frame, so the couplings only 'spin', not angle the way u-joints do. Once 'engaged' ( when you install the blower),it'd hard to understand the wear, except maybe from engaging the PTO at high speed.
I really need to see this setup 'in the steel', to figure out the wear. It appears to be a serious design flaw though.