I have a t190 I just bought from my grandpa. Everything works fine except for the brakes. When unloading from a trailer it will roll down the ramps on its own if I don't apply forward pressure. The parking brake works. When driving forward, if I try to turn slightly, the control gets loose and it is very jumpy as if the drive motor is trying to reverse itself in order to turn. The charge pressure on the display says 264psi at 2700rpm with a fluid temp of 112°F. And 187psi at idle.
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T190 jerky steering
- Thread starter Bjones386
- Start date
willie59
Administrator
Is this a standard control T190, not Selectable Joystick Control (SJC)?
It is standard control
willie59
Administrator
Ok, if I were there seeing myself what the machine was doing I might have a better idea of what's going on, but being disconnected from the machine via the internet I can't really say yet for certain what your problem is without some more information. But from what you describe, one thing that you should look for is a loose pintle arm on the pump on the pump control shaft of both left and right drive pumps. When those pintle arms get loose where they clamp to the pump control shafts a Bobcat will buck like a bronco.
Here's a thread that has some information about the pintle arms, check them out and let us know what you find. > https://www.heavyequipmentforums.com/showthread.php?19690-Repairing-creeping-Bobcat&highlight=
Here's a thread that has some information about the pintle arms, check them out and let us know what you find. > https://www.heavyequipmentforums.com/showthread.php?19690-Repairing-creeping-Bobcat&highlight=
willie59
Administrator
Bobcat machines don't have a "service" brake, they only use a parking brake that is spring applied when you either flip the parking brake switch on the center console, lift the seat bar, or shut down the engine. Once you release the parking brake by starting the engine, dropping the seat bar, and push the green operate loader button, the brake is no longer in play during machine operation. Anything that would be construed as brakes during operation would be when the drive pump swash plates are returned to null (neutral) which blocks oil from passing through the drive motors, thereby making a brake.
Up until recently, and by recently I mean the past week.. You could drive the machine as soon as the engine started running, even when the parking brake switch was on, and you were only reminded that you forgot to push the green button when it finally applied the brakes after running for a while. I checked the fuses and relays, all checked good. I'm not avoiding taking apart the Pintle arm assembly, I just want to reassure myself that, that could very well be the issue because it looks like a tedious job.
willie59
Administrator
First, I'm not suggesting you take the "take apart the pintle arm assembly", I'm only saying inspect it for a loose arm, you can typically do this without taking things apart, might require an inspection mirror.
Second, If you can start the machine and drive it without even pushing the green "operate" button then you have a curious problem. What about the loader functions, will they operate even before the operate button is pushed?
And then there's this,
I have never seen a Bobcat do that. I'd have to know a whole lot more about that machine to even have a clue what's up with that. Post anymore information if you think of anything.
Second, If you can start the machine and drive it without even pushing the green "operate" button then you have a curious problem. What about the loader functions, will they operate even before the operate button is pushed?
And then there's this,
I have never seen a Bobcat do that. I'd have to know a whole lot more about that machine to even have a clue what's up with that. Post anymore information if you think of anything.
In this video you can see my issue when turning. My grandpa has been running it like this for a while I guess. The boom and tilt will operate without pushing the green button. The parking break is working as it should with the switch, and the machine will not move without pushing the green button. And the Pintle arm assembly does not appear to be loose. I took a video of that too if you would like to see that also. [video=youtube_share;UBIW_9XbP2s]http://youtu.be/UBIW_9XbP2s[/video]
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