Snowblower Problem w/Kubota Front-mount Snowblower

[Edhof]

The Kubota snowblower I purchased in 1999 has Hydraulic
Chute Rotation (B2774). The (B2772) Blower has performed great up till this year.

About a month ago the hollow shaft on the worm gear that turned the chute broke near the hydraulic motor connection.

Looking into the problem, I found that the ends of the the worm gear itself and the last cogs in the left and right travel of the horrizontal chute gear were damaged from the contact they had when the chute was rotated left or right. Obviously, the speed and power of the hydraulic motor caused the damage when the worm gear abruptly hit the last cog on the chute gear in both directions. There is no buffer to lessen the impact when the gears reach the end of their travel in either direction.

I understand that Kubota has changed the entire design of the hydraulic chute control, but I don't know when. The blower was made in Canada for Kubota.

Has anyone had a similar experience with the same model snowblower and chute "control:? If so, what was done to prevent a new worm gear ($200) from failing every 4th or 5th year?
Any help out there? (I'm not getting much from Kubota.)
Edhof

 

[art]

We to date have not had one fail. The model you have has been changed and I have not found any updates for yours. I'd do a quick comparison by looking if you have a dealer sitting near by with one on his lot. I don't think there are any changes to that area that I know of. I would consider a modification on the turn piece to assist on the longevity of the part. You might consider extra support in the weak area before installing.

 

[Edhof]

art:
When you say "to date we have not had one fail" do you refer to the arrangement I have?
The arrangement I have was probably changed because it was poorly designed. There is no way to prevent the same thing happening again without slowing down the speed of the hydraulic motor and providing a "cushion" at both ends of the rotating travel.
Both ends of the worm gear and the rotaing gear it meshes with were "peened" from the collision that occured with each left or right rotation.
Thanks for your help. I wish I could get Kubota to respond.
Edhof

 

[art]

They can I just don't know what they will tell you. Some companies use a cable wrapped around and I know that fails. Some use a hydraulic motor and a gear which is quite positive and seems to work until it might get out of adjustment. Some use an electric motor and a shaft just like yours but they have far less torque then the set-up you have. You might try a type of restriction in your line but it will also slow your turn.

 

[Egon]

If your blower looks somewhat like this one then it may have been made by Buhler Industries in Manitoba.

The picture shows manual chute but they also made a hydraulic model.

Egon

 

[rambler]

You can put a restrictor plate (couple bucks at most) in the line to slow down the spin.

You can put a much more sensitive bypass valve in parallel with the hyd motor. This could be expensive.

You could be a little more careful & not slam the spout to full left or full right, just feather it when you get near max angle - if you need to go to max at all. Costs you nothing.

--->Paul

 

[keeney]

You could cut teeth into the ring around shoot all the way around so that it can spin 360 degrees. That would prevent damaging the worm gear by hitting the end. I added some additional rotation to an old walk-behind blower I had by doing that once (not all the way around, though).

On second thought, its probably not a real good idea to allow a full 360 degree rotation unless you have a cab to prevent getting snow blown in your face. Maybe just put some more teeth in on each end only to the point where you wouldn't be likely to rotate it past in normal use.

- Rick

 

[Rip]

Any one familiar with hydraulics should be able to put an adjustable flow restrictor in the hyd line to the rotator motor very easily. This will slow the motor down to give you more control to avoid hitting the end of travel hard.

If this does not give you enough control to prevent damage, adding a few more teeth notches at each end may also help as has been suggested.

A secondary pressure relief valve can also be installed in this circuit as a last resort, but would be more costly.

Rip

 

[Von]

Edhof,
Do you have any photos of the chute rotater and where it is braking? This is a post I did about Converted my snowblower chute to electric! Is this like yours. The electric motor will stop when it gets to the end of the teeth. It dosen't have enough power, but it will jam up on one side every once in a while. I just have to wiggle the chute to get it free. Sure would like to see a photo.

 

[Edhof]

Von:
The pictures of your blower look exactly like mine. The dealer installed the hydraulic chute control (I had expected a manual control) and it worked fine for 3 winters and a lot of snow. But this year was the first time a problem occurred and I had to tear it apart to find out what the problem was.
The shaft broke at the worm-gear-end of the hollow part of the shaft that connects to the hydraulic motor. It is obvious that both the worm gear and the horizontal toothed gear it turns were hitting each other fast and hard whenever the left or right limits stopped the rotation. Both gears were "peened" severly from the multiple collisions.
There was no warning in the instructions to alert me to a chute control problem where damage was possible. The speed of the chute rotation was so fast and so powerful that it is impossible to stop the action ahead of its limits. There are no rotation limits marked on the unit to tell where the limits are anyhow.
If I simply replace the worm gear and put it back the way it was, I'm positive that the same thing will happen again in a matter of time, and I will have to spend another $200 for another worm gear every 4 or 5 years, at best.
So I'm looking for a way to slow the speed down and reduce the torque so I can get some control over its travel before it reaches the limits, without doing Kubota's design work for them.
I'm sure your electric motor set-up would solve the problem, but I hate to convert the system without getting Kubota into the problem. Kubota caused the problem by selling something that was not properly designed. In my opinion, they should be held accountable. I have not been able to get any response from them in spite of 5 attempts to do so.
I was also hoping that someone else had the same hydraulic chute rotation system as I have to find out how they might have avoided the same problem.
I've had several good suggestions from this "thread" such as your, about how I can correct the problem, but I want Kubota to stand behind their standard sales pitch about quality and customer satisfaction, and get involved.
Thanks for your excellent input and very detailed information.