Kubota R510 Wheel Loader LST Issues

[Industrial Toys]

Does anyone out there know these machines intimately? Either they are not that common or they just don't break that often is my guess. I would have no problem taking it to the dealer, if I thought they knew anything about it. I don't feel like I should pay to have some mechanic figure out how the thing is supposed to work, never mind, possibly paying for parts that don't need replacement. I have already been told by dealers to try certain tests that indicate they really don't understand the machine at all. Not blaming anyone, just the way things are nowadays.

I have a shop manual, but it isn't great. Parts shown arn't there, translation is poor and flow charts don't address my problem.

I was operating for some distance on a roadway, with the machine quite hot, just below red.

Going down a rather steep hill, I let off on the accellerator. Rather then dynamically brake, something let go, and machine began to free wheel down the hill. Fortunately, the brakes worked.

At the bottom of the hill, I realized that I had no more forward motion, not hi nor low.

But reverse worked perfectly and got me home.

The Forward, reverse solenoid appears to work, juding by the clicking, although I am not sure if it works internally, correctly.

Switched hi pressure relief valves on the main pump reversing Forward and Reverse Ports with no effect.

There is the slightest forward driven effort when tried on level pavement and revving up the engine.

Tried some things on a grade.

Driving backwards DOWN a grade, machine does not dynamically brake when removing accelerator which is faulty.
At this point, it makes no difference if the selector is in Forward, Reverse or Neutral. It rolls back all the same.

Now, driving backwards up the grade, the machine stops instantly when accelerator is removed and holds perfectly in place. When put in Neutral, the machine starts to roll back down the hill and picks up speed slightly if put in Forward even without revs.

No ugly noises or oil leaking.

Any ideas? Thanks.

 

[Scooby074]

Anything you get on here will likely be a guess since I cant see nor try the machine

So if I was to guess, something let go in the trans. You need to take it to the dealer for diagnosis.

The R's are pretty tough. Ive seen them well beat and still working like a fine Timex! One of the largest landscape companies in the province uses them almost exclusively

 

[Industrial Toys]

I know its a long shot. I really found the right guy to talk to, but he is a mechanic at a dealership in Colorado and the service manager doesn't (understandably so) want me talking to him. I offered to pay for his time, but they have no mechanism in place to do that. This guy could look under my floor board and know what everything is and how it works. And I do say, there is a lot of strange hydraulic stuff under there. It's called experience! And probably some amount of enthusiasm! It took me a day, first cleaning, then taking pictures and comparing with the poor manual just to understand what half the stuff is.

I am an electronics technician and find myself working on a lot of unfamiliar stuff. I NEVER charge anyone for my time to learn (within reason) unless that was agreed in advance.

 

[Scooby074]

Of course there will be the cost of diagnostic time and getting up to speed involved. Its the nature of the beast. As a mechanic, sometimes you get lucky and its something youve seen before so its a quick fix, but the time to gain that knowledge was billed to the guy before. Just how it is.

As to the R's themselves, alot probably depends on the dealer. They are not uncommon. If your at a dealer that specializes in (or sells alot of) Kubota's construction equipment than finding a familiar mechanic should be easy. Now, a dealer that sells mostly farm tractors, or lawn mowers to homeowners, chances are they've never seen one before. I probably would NOT go to that dealer because the learning curve would be too steep.

Good luck!

 

[aczlan]

If you go to Kubota Tractor Corporation - Parts List you can pull up exploded parts diagrams. Not sure if that will help, but it might give you someplace to start.

Aaron Z

 

[Industrial Toys]

Unfortunately when I click on that link, it denies me access on account, I am in Canada. It seems that this society is really heading in a direction, where soon nothing (worthwhile or of value) will work any longer!

I have contacted a reccommended hydraulic shop, went there with my manual and had a little meeting of sorts. They told me to take some pressure readings which I will. Failing that, they will drive the hour or so distance for a modest charge and take a hands on look. I can work with them, learn a thing or two (I hope) and I am not just writing a blank cheque to a dealership, who then has my machine as ransome for payment of time and materials The dealerships are all very friendly and try and reassure me of their competence, but I have little more then zero faith in their abilities.

 

[Scooby074]

You can get Canadian parts fiche here. Kubota has separated their Canadian from US parts online. Kubota Canada Ltd. Parts

As to dealers, you should have faith in them. If you get one who is familiar with the construction side of the company, they'll have no issues. Id dare say Id trust them more than a independent shop for some things. This is coming from an ex-dealer mechanic, Ive seen the indys miss alot because they are not familiar with the idiosyncrasies of a particular machine like a dealership who sees them all the time is.

 

[Industrial Toys]

Sorry, I beg to differ. Maybe, I know too many behind the scenes horror stories from dealerships. While up front, the company passes themselves off as EXPERTS, factory trained, whatever! Meanwhile, I know, from a very demanding and smart (german) friend, that these industrial hydraulic guys know their hydraulics, no matter whos it is.

But again I say, it's only that these loaders are so **** reliable and bulletproof that there isn't any experience for the dealerships to draw on.

The other major issue I have is that with the hydraulic guys, I can talk to the guy that is actually going to fix it. Far better (and less frustrating) than going through a service manager.

Reminds me of the great experience I used to have with our local, one bay (with white painted folding wood doors), GM dealership until it was closed by GM after the 08 meltdown. I used to be working under my pickup along with the service manager/technician, at times even using my own Fluke test instruments to troubleshoot a warranty issue!

How is it that the world is going to crap in the name of progress?

 

[Industrial Toys]

I took some readings for the charge pressure. It was slightly high, and I turned it down. Might have been because I messed with the relief valve.

In the course of doing this, on account of some poor pictures in the manual, I connected the gauge to the wrong location, and got no pressures there. I think it was at that time, that the machine STARTED WORKING AGAIN! I kind of noticed that it moved but I really didn't pay more attention.

On a subsequent pressure test, we discovered that that machine had indeed become operational.

The only thing that appears amiss, is that there is a slight lag before she starts to go forward. It does not go forward slowly and smoothly but with a slight jolt. Worse with more throttle.

I am not sure if my connection to the wrong location had anything to do with the matter, but it is the only thing I did, because I am almost certain that it worked prior to adjusting the charge pump pressure.

 

[mtnman1955]

How do you adjust the charge pump pressure? Have the shop manual and owners manual can't find anything on adjustment but does tell me where to taking a pressure reading. Thanks