2008 KX91-3. Just did the 2500 hour service check. Changed all the filters and all the fluids. Used genuine Kubota filters, that hurt! Didn't touch or make any control or pressure changes but it feels like it has about half the power it did before. Tracks will stop if you run into a muddy hill. Bucket will not dig as powerfully as it did before. Affects every hyrdraulic control the same, hopefully that narrows it down. Any ideas, thoughts, comments are welcome, well, almost any comments.... Thanks in advance for any help.
Same weight oil?
did you bleed fuel system if so did you also make sure all old seals from fuel filters came off with the old filter,possibly sucking asmall amount of air?
Good question 250c. It is the same weight, ISO 47 I think I put in it so I can use it through the winter. I got it from Tractor Supply, I'm hoping ISO 47 is all the same, got to be right? A lot of oil to change but might be worth it if that is the problem, I'll check into it, thanks. The fuel system is working fine, you are right about the seal though, if somebody wasn't careful they could stick 2 seals on there, but I got the old one off.
I've had weird coincidences that just bit me in the butt and had me running in circles so it could be something that just Happened to fail at the same time. The oil would really have to be way off to affect power that much like if you put in 90 weight gear oil or some such. I did have an issue with a Hydrostatic Cat where they supplied a hydraulic oil filter that had a too small micron spec. Machine was very sluggish. Turned out they gave me a filter that was meant to be used after a system failure to clean out left over small particles. After running for a while it was supposed to be changed out to the standard filter.
Good thought, I'll check with the dealer to make sure I got the right filter. Has to be something in common with the oil change. Seems simple enough. Thanks everybody for the good thoughts and ideas.
Have you worked it 8 hrs? Sometimes these things have a way of working things out. Lack of power seems to be fuel related.
Sorry so long to get back to you. I am finishing building my house and since it is at least working, I thought I would leave it alone until the house is done. I put another 35 hours on it and it is still the same. The rpms are right at 2400 like they were before I changed the filters. No sputtering, no miss fires, engine starts and runs perfect. Still no normal power throughout the whole hydraulic system. The bucket, the boom, the tracks, everything is missing about the same amount of power. If you push forward on the right track lever it won't even move unless the left side is moving too. My neighbor is a tractor mechanic, when the house is finished I will have him take a look at it. Frustrating because it is probably something really simple.
I had a similar problem, took me a while to work out, I got out of my bobcat mini and on return everything was slow and no power. Thought the worst and could see big bills coming but, it turned out I had disrurbed the foot pedal for the breaker feed and it had not sprung back to centre properly. Had me worried for a while but it was only something simple in the end, might be worth a look to see if your pedals are all in the fully off position?
Wow, I will be so happy if that's all it is. I will check it out first thing in the morning. Like they always taught us in any mechanical school, always check the simplest, cheapest things first! I'll let you know what i find out, thanks for the thought.
Older Kubota KH-033 excavator. (Grey market). No computer, levers instead of joysticks..... Total loss of hydraulics overnight. All functions worked fine the day before... next morning the engine started as usual but absolutely no response from any controls. Engine revs up as usual. The hydraulic oil tank is full, filter is fresh about 10 hours ago. There is one thing, though. There is a large hose connected to the back of the fuel injection pump to what looks like a small pump, and to a manifold that I think is a return to the oil tank. This hose is always collapsed as if it is under vacuum. I don't think the conditions are related, as the machine works fine even with this hose collapsed. Anything on the no hydraulic problem would be appreciated. I cannot move the machine. Thanks,
Good luck figuring out your problem. I still haven't figured mine out yet. Frustrating because the hydraulic system is basically a simple system. Maybe I need to start looking at my problem with that frame of mind instead of looking for a big, expensive problem. Again, good luck. JB
So I drained the oil tank and found the screen completely clogged up with a varnish type of stuff. I was able to clean it with paint thinner and compressed air. Put it all back together, confident that a completely clogged screen would cause a low flow or even absent flow. Started the machine, same problem! I am now going after the piping and hoses that supply the pumps. The manifold pipe couldn't be located in harder place to access so I'm not looking forward to it. I am hoping to find a blockage of some sort and not broken pumps.....
I'd be checking the coupling between the motor and pump. Just a thought. jr
I know nothing about the components on a KH-033, but whatever your are describing connected to the back of the injection pump does not sound like the main hyd pump that would operate machine functions, the main pump should be driven by engine flywheel. If you drained the hyd tank and found the strainer was completely clogged, and if the machine uses a hydrostat pump for main pump, it's possible you've emptied the pump of oil and it now can't purge the air locked in the pump. Just a thought.
There is a third pump driven off the fuel injection pump that provides additional oil flow for the faster travel speed. I ended up draining the tank again, removing the strainer and putting enough oil back in to see if I had flow to the supply side of the pumps. Sure enough, oil showed. So I reinstalled the strainer and the flow stopped. I said, screw it, and took out the strainer and refilled the tank. I watched for oil flow to the top of the pump fitting blocks, and after some time of air purging, I had flow to all pumps. I reassembled everything and everything works, even better than before. I guess diligent attention to cleanliness and frequent filter changes will make up for the removed strainer.
Geeze, I can see that working out well in the long run...
I've been light working the machine now for a couple of days, seems ok now. I is still a mystery why the oil will not flow through the strainer - maybe everything is worn out to the point where it can't pull oil anymore? But then I don't think I would have as much functionality as I've got. Anyway, I am going to run for a while this way. My next question is does anyone have a regular trailer hitch reciever assembly attached to a bucket? I would like to launch the boat with this machine....
I would like to see some pictures of the ball hitch if anybody has some, I have a need for the same thing.
do you still have machine i have the same one and having a hard time locating a manual and parts?
looking for manual and parts for same type of machine
I would get your oil sampled, its only 12 - 15 dollars. Its weird that your screen was clogged that bad. Sampling could give you some direction on what to look for.
Still have the machine. Been so long now I've gotten used to the less amount of power. Just have to take 10 times longer to pull out a stump. Only manuals I can find are through the dealer, seems like nobody makes or sells any manuals for this type of machine. Just lube yourself up well and get ready for the overpriced Kubota dealer!