B2601 Power Steering Not Working Correctly?

[JustinB60]

I had my tractor picked up by dealer because when I was moving some topsoil around my property I noticed that I could not move the steering wheel at all back and forth when the machine was sitting still. When I would creep forward the steering would work again, this seemed to be worst when tractor was hot. I also noticed an occasional drip of fluid wherever I had to turn sharp. It seemed to get a little worse over time, to the point where right before they picked it up the tractor wouldn't turn steering wheel back and forth in the grass with an empty bucket! There is a noise like the power steering is trying to go but it just doesn't move the wheels at all, steering wheel gives feedback almost as if I'm pushing against a rock, it won't budge unless I really crank on it which I only did once to see if it would turn that way... it barely did a few inches.

I asked dealer to start off with checking hydraulic pressure, they said it checked out fine. They also said that this "might be normal for this type of tractor" as they aren't sure they've ever tried the same maneuver on another machine. Has anyone ever had this issue? This doesn't seem normal at all to me. They claim my front tires were like 5-10psi low... but if thats the issue then this front steering is pretty weak in my opinion.


Any thuoghts?

 

[BAP]

Was your bucket full and off the ground? Did you check the hydraulic fluid level? Were you at an idle or reved up pretty good?

 

[JustinB60]

Was your bucket full and off the ground? Did you check the hydraulic fluid level? Were you at an idle or reved up pretty good?

My bucket could be just 1/2 full and it would do the same thing. In fact when I drove through about an inch of mud and stopped with the bucket empty it did it then too.

Hydraulic fluid is clean and full. I was revved up to about 2000RPm and then when it did it I tried Max RPM and same thing.

 

[MikeyA]

It sounds like the center seal inside of steering ram has let go.

 

[Steve67]

Power steering on my tractor works with ease moving or sitting still, hope dealer finds the issue. Somethin ain’t right

 

[Bmbbm]

Sounds like a seal in the ram to me... Just guessing.. Had my old BX2200 do something similar.

 

[North Idaho Wolfman]

tractor wouldn't turn steering wheel back and forth in the grass with an empty bucket!
Steering wheel gives feedback almost as if I'm pushing against a rock, it won't budge unless I really crank on it which I only did once to see if it would turn that way... it barely did a few inches.

You have a bad hydraulic feed to the steering unit, or more likely a bad steering unit, or far less likely a bent steering ram.
It's not a bad steering ram seal as you have extra resistance on the wheel and the wheels aren't moving, a bad ram seal would present as no extra resistance on the steering wheel and the wheels either not moving or moving sluggishly.

They also said that this "might be normal for this type of tractor" as they aren't sure they've ever tried the same maneuver on another machine.

I really hope your dealership is truly not this stupid! "Might be normal"?
Normal for a 1945 Studebaker, but not a Kubota with Hydrostatic steering!
Your steering should work at any RPM and with all the weight it's rated for on the front wheels, yes even with a fully loaded Bucket on the FEL!

 

[JustinB60]

You have a bad hydraulic feed to the steering unit, or more likely a bad steering unit, or far less likely a bent steering ram.
It's not a bad steering ram seal as you have extra resistance on the wheel and the wheels aren't moving, a bad ram seal would present as no extra resistance on the steering wheel and the wheels either not moving or moving sluggishly.




I really hope your dealership is truly not this stupid! "Might be normal"?
Normal for a 1945 Studebaker, but not a Kubota with Hydrostatic steering!
Your steering should work at any RPM and with all the weight it's rated for on the front wheels, yes even with a fully loaded Bucket on the FEL!

@North Idaho Wolfman or anyone else who knows a lot about these tractors...

Dealer contacted me today. They've replaced the hydraulic pump, the steering hydraulic cylinder, and the steering unit itself. The dealer also claims they've checked the hydraulic lines going between the hydraulic pump and the steering system and they are not the culprit.

The unfortunate part comes in his next portion of the discussion...The Dealer then tried to say that the problem seems to be the loader because whenever they take the loader off the tractor steers fine at a stand still but with loader on the front steering is limited or even stops working. I explained to him its due to the extra load/resistance on front end. I got him to agree to that and he is going to keep workign with kubota to try to figure out what the problem is.

Do you have any other ideas of what to check next? Any suggestions are appreciated!

 

[North Idaho Wolfman]

It is very possible that the loader control has a fault in it that would cause it to stick in a relief position and bypass fluid thus making the steering not work.

Wow they are throwing a lot of parts at it and don't seem to even know how to test the system.

 

[100 td]

Wow they are throwing a lot of parts at it and don't seem to even know how to test the system.

Seems to be the norm these days...............

 

[100 td]

Something to consider, maybe?
I had a quick look at the parts diagram, I don't have a service manual, from the parts diagram I conclude the following. It may not be correct, so happy to be corrected.

It "appears" the "separate hydraulic steering pump" is indeed separate from the main hydraulic pump and circuit supplying oil to the FEL and 3pt.
This separate pump supplies fluid to the controller, out to the ram, back to the controller, fluid exits the controller to the oil cooler, through the PTO valve to the transmission.
"If" this is actually the case.........
They have replaced the pump. Why, was it's output pressure and flow not to spec?
They have replaced the hydraulic cylinder and steering unit, well I guess they mustn't have made the test regime either?
So everything is new, whats left?
If there is a fault in the PTO valve, or squashed oil cooler line, and oil flow is being excessively restricted from returning to tank from the controller, I expect it would certainly impact on steering function.
Since they have replaced everything in the steering circuit up to the cooler, you could ask them to remove the controller to cooler line and run it into a bucket and see how the steering responds. (I would also check the PTO valve first though)

Without looking at the hydraulic circuit schematic, I'm unsure what goes on in the PTO valve, what pressure the steering circuit is held at and how it utilizes return flow from the controller to actuate the valve, but if the poppet valve in it is stuck then fun things could happen. YMMV.

 

[JustinB60]

Thanks for the input fellas! IVe shared some of this information with them and hopefully it helps them out.

To be honest Im annoyed by the amount of time theyve had the tractor but Im even more annoyed by imagining how many more hours will be on it when I get it back after a month of repair, test, repair, test, etc. Hope Im getting it back with as few hours as possible, as the month without a tractor is already a big enough issue. Im having to rent another machine here in the near future in order to keep getting stuff done in my back yard project.

Is there some sort of statute of limitations on repair attempts duration? I know with cars its 30 days or more in the shop for a repair attempt and you get a replacement vehicle... anyone know if there is any set consumer protection for tractors? I know dealer is trying to fix it... I imagine they are as tired of this as I am, but at the end of a day a tractor in the shop isnt getting me any closer to finishing my projects and I need this to get resolved!

 

[Russell King]

Perhaps the dealer can loan you a tractor until you get your tractor back? Can’t hurt to ask!


Sent from my iPad using Tapatalk

 

[100 td]

I had a look at a another tractor with a similar hydraulic circuit, PTO relief valve was set at ~70lbs, the circuit also supplied the HST, so I expect the line is held at charge pressure for the HST circuit, relief set @ 80~100 lbs. (I thought I looked at another where the PTO relief was @~200 lbs, but was too tired so don't recall if the circuit was close enough to compare)
But if the HST charge relief or PTO regulator/relief valve was playing up it would create the same result I expect. Removing the hose at the cooler would leave the steering circuit totally isolated for testing. I expect the HST circuit could run in neutral for a short time without supply, but this timeframe would need to be considered carefully.

If I were doing the testing on my own machine, I would install a pressure gauge teed into the cooler line so continual monitoring the steering return line at 70~100 lbs (or whatever the specs are for this machine) could be done and still be supplying the HST with oil. Any substantial increase in pressure would require investigation. This would also allow extensive testing/driving/operating under load.

Whilst unlikely, the HST filter may be between the PTO and HST relief, if there were contaminants in this filter the line pressure would be increased.

Whilst everything they have done is about hydraulics, I hope they have also checked the front axle/steering components properly to ensure there is nothing binding in them. Good luck.

 

[ipz2222]

And you shouldn't have to pay for the parts that didn't fix the problem!!!!

 

[100 td]

And you shouldn't have to pay for the parts that didn't fix the problem!!!!

I haven't read that is was a warranty job, but pressumed it was.

 

[JustinB60]

Yes this is a warranty job... I noticed it acting up and got it into dealer a couple weeks before full warranty expired (will still have a couple years of Powertrain left when/if I get it back.

I will talk to the manager or tech today and share this information with them!

 

[lugbolt]

Ask them to get their regional service rep involved. I hear that he's a pretty sharp tractor guy.

 

[JustinB60]

It sounds like regional service rep is getting involved either tomorrow or Wednesday.

Talked with service manager again today, Im at a loss for words now. If they only knew how far this has put me behind on projects and how much money Im out because of this delay. Because I have been without a tractor for about 5 and a half weeks now Im borrowing from friends (which means Im renting trailers), renting equipment, and I event got to a point where I have purchased another piece of equipment to try to keep things going forward. Im now to a point where even if I got my tractor back tomorrow in perfect working order Id still be out so much money and personal time that Id be getting screwed. Sorry to vent here guys but Im just tired of saying the same thing to the service manager every few days for weeks on end.

 

[lacasmi117]

WSM available on kubotabooks.com for future reference, that being said, running a B2301 for over a year now, never has this issue come up, bucket loaded or unloaded, nor should presence of leaks be "part of this tractors design"