Kubota MX4700- Steering Locks Up when Loader Used

EuropeanAM · Nov 4, 2010

Let's see if anyone here has any ideas....

2009 Kubota MX4700 with less than 35 hours. Loader equipped 2WD model.

When NEW, steering worked flawlessly. Carried 800# on loader while steering with one finger.

At around 15 hours, the steering began to LOCK one way or the other anytime a load was on the bucket or forks. Doesn't seem to matter how much weight.... even 350# causes the steering to lock. Added RPM's make NO difference. Neither does dropping the loader back to the ground.

Problem seems more pronounced in warmer weather (80+ degrees). Once the steering locks, you have to set the load down, back up (steering still locked), and shut the tractor down for several minutes. Restart... 90% of the time normal steering function returns.

Been round and round with local dealer, Kubota Technical and Field Rep. Filters replaced, pressures checked, counterweights added, tire pressures checked, etc. etc.

Last communication with them was told "2 wheel drive tractor with loader won't steer with load on loader... you should have 4 wheel drive model". Offered to upgrade to 4 wheel drive for "X amount of dollars".

Still going on after 6 months.... called the field rep last week and said we'd agree to the upgrade (don't really NEED 4WD, but if it solves the problem... that is what we need to do). Told me the dealer would call us..... but no call after one week.

Really beginning to get aggravated.... love the tractor, but it kindof defeats the purpose of having a loader and forks IF YOU CAN'T STEER!!!

Suggestions???? Would really like to get this taken care of, or fixed. Stinks that we have to spend thousands of dollars to "fix" it, but if that's what's necessary.....

jinman · Nov 4, 2010

I would ask the dealer/rep one question. Why would they sell a configuration that will not work? If you added the loader after buying the tractor, then they might have a tiny bit of justification for their premise, but if they sold you a tractor with a loader, my demand would be that they make it work correctly or take the tractor back. Besides, I'd bet if you asked them to give you the details of why power steering would work better with 4wd, they'd be "blowin' smoke" your way.

My tractor is 4wd and may stall the power steering while it is sitting still, but as soon as I roll a couple of inches, it begins to work fine. The fact that you have to shut your tractor down and restart tells me that there is a cavitation, airlock, or some other malfuntion that has to bleed off before the power steering pump and control motor will work. Why oh why would you buy another tractor from somebody who couldn't make the first tractor work as it did when new? I think you're being fed a ration of BS and you know it. Don't let them off the hook. Be respectful, but be firm.

Treemonkey1000 · Nov 4, 2010

I would agree the dealer is blowing smoke. Espcially since the tractor worked fine at first. Cavitation like the other guy said. Or you may have bent part of the frame or steering linkage. Up grading to 4wd is going to give you more power in the mud or snow is the only benefit. Still for them to sell you that rig and not be able to drive around with a load in the bucket is nonsense.

art · Nov 4, 2010

I'd try changing dealers! It is under warrantee.

Gator6x4 · Nov 4, 2010

If memory serves several New Holland owners have posted with having the same problem when using a loader on a 2wd unit. You may do a search and see what their resolution was.

mrmikey · Nov 4, 2010

Not familiar with a Kubota system so I may be way out in left field here.
If it uses the same pump for the loader and power steering there may be a splitter valve in the circuit (if they don't use a power beyond configuration). If so, it sounds like the spool in the valve is hanging up, expanding due to heat. That would explain why shutting it down for awhile allows it to work, it allows the spring to center the spool once things cool off.
Just for the heck of it, trace out the plumbing from the pump and see if there's a splitter there, if there is the next time it screws up give it a sharp rap with a hammer......Mike

nikdfish · Nov 4, 2010

Back when we were shopping around for a tractor, we were talking with a Massey Ferguson dealer who described exactly the same thing happening with some of their smaller models. He had had customers that could not turn the steering wheel while standing still with a full load in the bucket.

He said the problem they had run into was the factory arbitrarily setting too low a pressure on the power steering pump, well below the pump's capacity. The fix they finally got the factory engineers to sign off on was increasing the size of an output aperture on a plate on the pump, which raised the pressure of the steering hydraulics to be comparable with that of models which didn't have the problem ...

Nick

woodlandfarms · Nov 4, 2010

So, I don't have this in question, but I can tell you a weirdness with mine that might relate.

PT's do the same thing, Can't turn when tilting or dumping (well, you can but tilt dump slow down a bit and sometimes stop).

it is related to the following on our machines. The pump that drives steering drives lift and tilt. It has a charge valve that keep the pressure up on the system.

My thought is that your charge valve (if you have one, it is this little gas cylinder looking thingy) might be empty. Sometimes they discharge.

Carl

jinman · Nov 5, 2010

The MX4700 has a dedicated 4.9 gpm power steering pump and a separate 9.5 gpm main hydraulic pump. If 4.9 gpm can't steer that tractor with 800 lb in the FEL, it's a sad, sad hydraulic day.

Treemonkey1000 · Nov 5, 2010

jinman said:
The MX4700 has a dedicated 4.9 gpm power steering pump and a separate 9.5 gpm main hydraulic pump. If 4.9 gpm can't steer that tractor with 800 lb in the FEL, it's a sad, sad hydraulic day.

I agree with you Jinman. Maybe as someone suggested there is a valve that is sticking or crudded up. I would be an unhappy camper if that were my tractor having to shut it down to get the steering back..

Kernopelli · Nov 6, 2010

Wow, I would think this is a pretty basic set up, (I am guessing) if you break the system down it's going to basically look like a pump, orbital valve, hoses/tubing and cylinder...and the dealer, Kubota tech and field rep "can't" diagnose and fix it.....give me a break. As was mentioned before, if this tractor "can't" work w/ an FEL, why are they sold w/ this option...give me a break.

I too would suggest contacting another dealer and giving them a shot at it. I don't know much about them but I think most orbital valves have the relief valve built into them. If it were mine and I was having to try to fix it myself I would start with putting a gauge in various locations in the hydraulic circuit and see what's going on when the problem occurs. It sounds like the relief valve is opening at too low of pressure and then sticking open ( or simply staying open, even under reduced pressure after opening -for lack of better way of saying it). This might explain why the tractor has to be shut off to get steering function back.

Whatever the problem is, the tractor is nearly new and shouldn't be behaving this way...it's really pretty dangerous. Kubota should have little problem with finding the issue and making it right and I'd make every aspect of the warranty, their responsibility and my options clear to them.

firefighter jim · Nov 6, 2010

It's a new tractor that is under warranty and it doesn't work.... Return it to the dealer and have it fixed. Period....................If the dealer can't fix it, have him refund your money and buy something else...............

EuropeanAM · Nov 12, 2010

Update:

After multiple attempts, finally got to speak with a District Rep. He told me I had to talk with the dealer to work it out.

Well... that conversation went well. Dealer says we have to pay over $6000 to upgrade tractor to something that will work (a 4WD model)... they're not going to work on this one anymore.

We HATE attorneys and lawsuits.... and since what we really want is for this thing to be REPAIRED (or replaced only if it can't be repaired- surely this is a reasonable request)... we contacted the local Better Business Bureau and filed a complaint.

Took the dealer all of six hours to respond to the BBB:

----------------------------
"Mr. and Mrs. X are not stating all of the facts. The tractor is performing to factory specifications and mis-use is not a mechanical or manufacture issue.
This matter is closed.

Mr. Owner (name removed)
Owner
(Name Removed) Tractor and Turf Equipment"

---------------------------

Misuse? I don't know where that comes from (it's certainly the first time we've heard him say that). This unit has been cared for, hasn't ever been over-revved or overloaded (if it won't steering with 800# on the forks- it's a little hard to imaging overloading the 1800# fork/loader combined capacity), is clean, nubs still on the tires, and only 33 hours!

Anybody have a contact AT KUBOTA that might be capable of discussing this?

jimmer2880 · Nov 12, 2010

I can't believe this. 100% irresponsible for Kubota to allow this dealer to treat you like this.

I would understand if it was an aftermarket loader, but it's not. Do you have any ability to respond to the BBB reply from the dealership?

I hate to say it, because they are usually the only ones who make out, but I see an attorney in your near future. Good for you, to wait this long. Personally, I agree with you about attorneys.

Joe H · Nov 12, 2010

This is complete BS. These people are screwing you and the factory rep is going along with it?
Why are you blocking the dealer's name, let the world know how these people treat their customers.
Don't know where you are, European kinda leads me to think you're in Europe?
If you're in the US there is a state consumer protection agency that you can contact. They sell this tractor with this attachment, it did work and now it doesn't and it's your fault?
Give me a break, my grandchildren can come up with better lies than that.
Joe H

jimmer2880 · Nov 12, 2010

My guess, is that they are required to show proof of misuse, or proof that you are trying to do something it's not designed to do. I would be sure to let the BBB know that they haven't done that.

You simply have to produce the tractor and loader specifications stating it will lift what you are lifting.

IMO - They committed fraud, selling you a tool that doesn't do the job they said it would.

Hooked_on_HP · Nov 12, 2010

Let the BBB know that they did work on it under warranty and that abuse was never mentioned untill they couldn't fix it. How about posting some pics of the tractor.
Bill

Treemonkey1000 · Nov 12, 2010

This was the specs posted on one dealers website
GENERAL INFORMATION
Manufacturer Kubota
Model Year 2010
Model MX4700 (2WD)
Retail Price $15,999.00
Price *$14,999.00
Color Orange
MEASUREMENTS
Length 127.8 in. (3,245 mm) without 3P
Height 95.7 in. (2,430 mm) top of ROPS
Width 69.7 in. (1,770 mm) minimum
Weight 3,369 lbs. (1,528 kg)
Wheelbase 74.6 in. (1,895 mm)
Turning Radius 8.5 ft. (2.6 m) with brake
Fuel Capacity 12.6 gal. (48 l)
Ground Clearance 15.9 in. (405 mm)
ENGINE
Engine Type E-TVCS
Engine Make Kubota
Engine Model V2403-M
Fuel Type Diesel
Cylinders 4
Gross Horsepower 48.2 hp (35.9 kW)
Net Horsepower 46 hp (34.3 kW)
Injection Indirect
Aspiration Natural
Cooling Liquid
Displacement 148.5 ci
Air Cleaner Dry-dual element
DRIVETRAIN
Transmission Type Mechanical shuttle, dry single plate clutch, rear standard (mechanical) differential lock
Number of Speeds 8 forward / 8 reverse
Drive Type 2WD
Tire Size Front: 7.5L-15
Rear: 14.9-26
Brakes Mechanical wet disc
Speed - Forward 1 - 16 mph (1.6 - 25.9 km/h)
Speed - Reverse 0.9 - 14.7 mph (1.5 - 23.7 km/h)
Steering Hydrostatic power
ELECTRICAL
Alternator 45A
HYDRAULICS
Standard Pump Flow Main: 9.5 gpm (35.8 l/min.)
Power Steering: 4.9 gpm (18.6 l/min.)
OPERATIONAL
Power Take-Off Live independent, hydraulic PTO with PTO brake, wet clutch
PTO Horsepower 39.5 hp (29.4 kW)
PTO Speed 540 rpm
Lift Capacity 2,310 lbs. (1,050 kg) at 24 in. behind lift point
Hitch Category Category I & II

EuropeanAM · Nov 13, 2010

Never low on oil.... at least not until the dealer attempted to replace the hydraulic filter when the problem developed.

Were in the Greenville, SC area, BTW.

I happen to be a Master "rated" technician for a specific line of Marine Engines (which includes some very intricate electronic "fly-by-wire" and hydraulic controls), so I'm at least "vaguely" familiar with the workings of a hydraulic system.

Here's the response sent back to the BBB (for those of you interested):

---------------------------
We do not understand the dealer's comment about mis-use, and Specifically REFUTE AND DENY that this unit has been misused in any way, form or fashion. The dealer was informed (in the presence of a witness) of exactly what we needed the unit to do, exactly what the intended "particular purpose" for the tractor was, and chose a specific unit (which we agreed to) from his inventory. He then specified the loader, the forks, the bucket, the quick attach bracket, and other accessories via his computer system to put together a complete purchase that "would" work together to suit our needs. Dealer was fully aware of the exact nature of our intended use, and made no indication that the tractor would not steer when being used as intended. At no time prior to purchase did the dealer indicate that "a 2WD model cannot be steered when using the loader with forks". Dealer assembled the comlete unit and delivered it as "one sale".

At no time has the tractor been used to pull, lift, move or carry any weight that is not within the specifications listed within the Kubota Owner's or Users Manuals (one of which we had to request, as it did not come with the unit).

Dealer specifically informed us that the loader (with forks) was rated to lift and carry 1800 lbs. We even discussed what specific items would be on the loader forks most commonly. It cannot be steered with 1/2 of that weight- and the steering "locks" to the left with less than 400 lbs. on the forks at times. This was not the case when the tractor was first purchased- it would originally steer effortlessly with 900 lbs. on the loader (problem began abruptly at around 15 hours on the hourmeter).

We have expressed to the dealer (and the manufacturer, Kubota) that this problem is not only preventing us from using the tractor for it's "particular purpose"... it poses an obvious safety hazard to persons and property as well.

We firmly believe that the problem is in a control valve or cylinder for the steering. Unfortunately, it is not appropriate for us to diagnose or repair the tractor- by direction of the owner's manual that should be done specifically at the selling Kubota Dealership.

Again, we simply want the unit repaired (preferably)... or if it cannot be repaired, we would want it replaced with a comparable unit that functions properly. In an effort to help bring a closure to this situation, we even offered to meet the dealer's original offer of $2500 to upgrade/replace the tractor... to which he responded "that offer is off the table- it will be upwards of $6000 now..."

--------------------

I've not named the dealer because I'm not a vindictive person (although it's been a bit trying to remain that way given the circumstances). Simply trying to find a reasonable solution that will restore our confidence in our purchase.