L4150 HYDRAULIC ISSUE

[nightowl490]

GOT ONE FOR YA ALL..... I had to run over to my farmer friends house to pick up a 12" auger (It's a real meat hog!) It's about about a 6 mile trip in road gear, approximately 20 minutes. A little over halfway there, my hydrualic light comes on. I of course continue to my destination and everthing is fine. After hooking on and shutting off, I hang out and leave without a light coming on. Drive back, use the implement, and return, again, halfway there my light comes on. When I get there I have no FEL operation, even under RPM. If it does move it's jerky and RUFF! I then hook on a shredder to 3PT and cannot even lift it. WHAT IS HAPPENING????

I ended up parking it, letting it cool off and restart after a few hours. Light is still on but now everything works??????????????

Only 50 hours on complete fluid change including filters and plenty on the stick...

IS IT GETTING HOT AND THE OIL THINNING- Engine was never hot....

IS THE FILTER CLOGGED OR SOMETHING- Sometimes it works sometimes the light just comes on......

ANY RECCOMMENDATIONS.... I WAS THINKING JUST A FILTER CHANGE OR A COMPLETE FLUID/FILTER CHANGE.

USING udt, NOT KUBOTA, GOOD STUFF FROM A FARM & HOME STORE.

Tractor has 1750 hours on it and if you are using it without heavy RPM for easy tractor work it's a horse. If you run it in it's guts, the light comes on. Today is the first day it has done the hydraulic dance.

YOU GUYS ARE THE BOMB, I'M A HEAVY READER, LOOKING FORWARD TO HEARING FROM Ya'LL...

Thanks

 

[TedLaRue]

Since both the 3Pt hitch and the loader were not functioning properly, the problem must be something in common with both. That could be your intake screen, hydraulic filter, pressure relief valve, or your pump. Let's hope it's not the pump!

... When I get there I have no FEL operation, even under RPM. If it does move it's jerky and RUFF! ...

That jerky operation was probably caused by the hydraulic pump being starved of fluid.

You didn't say whether you checked the level of your hydraulic fluid. Being low on fluid could have caused the problems you described. Did the light come on when you were driving up a hill? That would be another symptom of low fluid level.

Another common cause of this is a clogged intake screen. A common cause of a clogged intake screen is a hydraulic cylinder going bad (pieces of the failing seals plug up the screen). If you clean the screen and find a lot of tiny pieces of rubber clogging it, you probably have one or more cylinders which need rebuilt (new seal kits installed). If you don't find and fix that or those cylinders, you'll have the screen plugged up again in short order.

A clogged hydraulic filter could also cause jerky loader operation, but your filter shouldn't be clogged after only 50 hours unless your screen is also clogged because of a cylinder breaking down.

However, if your fluid level was good, a plugged screen or filter wouldn't explain why your light came on while you were driving.

... IS IT GETTING HOT AND THE OIL THINNING- Engine was never hot....

The temperature of the engine and the temperature of the hydraulic fluid are not related. When you're just driving, the hydraulic system isn't doing much except, perhaps, for your steering. But the fluid may get hot just from lubricating the transmission, so this could contribute to your problem, especially if you have a worn pump. But let's hope it's not the pump.

First, check the fluid level. Then try cleaning the take-up screen and replacing the filter. The first time this happened to me, the screen didn't look like it had very much debris on it, but I cleaned it and that solved my jerky loader problem. Also note whether the take-up screen is clogged with fragments of rubber, indicating that you'll probably need to have a cylinder or two rebuilt.

I hope you get this figured out, nightowl...and if you do, be sure to tell us (and more importantly, future readers) what the problem was.

 

[rbargeron]

Hi Nightowl - sounds like a clogged filter - sent you a pm. The filter is on the suction side of the pump so it doesn't take too much blockage to put it out of business. When the filter cartridge is changed, there's also a magnetic filter there to take out, clean and screw back in. I doubt the brand of fluid is involved here.

 

[nightowl490]

Even the manual relates to clogged filter and I had no popping sound at road speeds. Oil level at hot was 1/8 inch below full. Unknown if updated sump kit installed on this tractor. At cold, or even after warmup work, no light, only after hard labor. That is the one that gets me the most. I did read on TBN of floating debris in system. I will do filter change and cut open for debris. Also check screens for clogging. I will refer to shop manual for screens. Are they on the pump houseing where it's mounted? I'll have to find it. Once you tear into them (with patience) things go pretty well. {Finger's crossed}. As far as a pump rebuild. We Will See..... Oil levels were fine so I'll start with simple first.

 

[nightowl490]

Thanks for info and ideas. Much appreciated. Will keep you posted on this and even If I need a pump rebuild, it doesn't appear to be to awful difficult. Maybe a good early winter project if I can last the fall..............

 

[Wayne County Hose]

Typical symptom of fluid aeration.

 

[rbargeron]

.......When the filter cartridge is changed, there's also a magnetic filter there to take out, clean and screw back in........

the later L3 models have the magnetic filter described above - but the parts book for the L-4150 shows only the cartridge filter at the intake end of the hydraulic supply pipe.

 

[nightowl490]

Thanks again for comments everyone. VERDICT...... French Fried Hydraulic pump. Not an everyday problem but one that cannot be denied when it goes out. Should be up an runnning in a couple weeks. Gives me chance to look for a backhoe attachment.

Thanks again

 

[kmdigital]

So how are you fixing the pump? Installing a new one, or rebuilt or rebuilding it? How much $$$? How did you diagnose the bad pump?

I have the same tractor, so it would be nice to know if it ever happens to me.

Mine did the same thing a few years ago, but the problem was the Kubota repair shop that had split the tractor and replaced the clutch before I got it didn't keep the old gasket material out of the tranny area. When I took the filter off, the oil wouldn't even come out (didn't drain it first) and then when I started poking around all these pieces of gasket material were jammed up in the filter inlet area of the filter mount. Picked as many out as I could, with oil pouring out to help flush them out, and installed a new filter. THen I removed the center drain, and did the same thing, using my a piece of wire to drag anything towards the hole that was in this low area. Filled it back up, and it's been fine ever since.

 

[art]

GOT ONE FOR YA ALL.....

USING udt, NOT KUBOTA, GOOD STUFF FROM A FARM & HOME STORE.

I guess the farm and home store knows more about what the Kubota tractor needs then Kubota?