BobCat T190 travel problems- lockup

[steve(ill)]

Son just bought a 2006 Bobcat T190. First week ran 8 hours a day. Now runs great for about an hour, then all of a sudden the tracks lockup. Travel levers are hard to push. Will drag motor rpm down and stall out if you push hard on the levers. If he jerks the levers around back and forth, something seems to pop loose, then he is ok to go again... might last 5 seconds or 5 minutes then do it again. Seems to run o.k. for the first hour. I don't have a manual yet, trying to figure out if this is solenoid (electrical), solenoid spool, hydraulic spool, or other. We did change the hydraulic oil after this happened, and it still occurred the next time he ran it.. Other than that, its a great machine.

 

[willie59]

Welcome to HEF steve. :drinkup

Without the benefit of looking at the machine myself it would be hard for me to say exactly what's going on. Yes, you could have a problem with the parking brake valve, but I kinda of doubt it, jerking the levers back and forth typically doesn't fix a fault with the parking brake valve. As for something "popping loose" I would think a problem with the drive motors. But then, the odds of both drive motors going bad at the same time would be a Las Vegas bet.

Question, when it locks down, is the green LED light for the traction lock on the BICS panel lit up, or is it off?

 

[steve(ill)]

As far as I know willie, there are no light. When / if it does "pop" loose it seems to run o.k. so I don't think it is the drive motors. He does say the levers "don't want to move" or "move real hard".. I was hoping that would give someone a clue to the problem. I know nothing about the tractor, but since it happens real quick, and only after it is warmed up good, I was thinking a spool is sticking in a bore... just don't know if it is a pilot type spool (hydraulic),, or more of a solenoid spool ? Im assuming it has both ?

 

[willie59]

No, you need to familiarize yourself with the Bobcat. The BICS system (Bobcat Integrated Control System) has 4 LED lights on the left cab console, one of those LED lights is the traction lock (parking brake). When you start the machine, let the seat bar down, and push the green enable button on the BICS panel, if all things are good, all 4 LED lights will light up and stay lit during operation. What I need to know is...at the very moment that the machine locks down...is the LED light for the traction lock lit up or no.

 

[steve(ill)]

OK... I will ask the kids. I have never run the machine.. I have seen the seat bar / lower and I have been told the problems.. Will ask about the light.

 

[willie59]

Good, thanks. You do have a strange problem, and the very first thing we need to know is if the traction LED is lit or not when the machine locks down.

 

[steve(ill)]

Boy is working OT right now and may be unavailable for a few days. I will repost when I see him again. Thanks willie... and I will be back !

 

[crewchief888]

and the very first thing we need to know is if the traction LED is lit or not when the machine locks down.

if the light is flashing, you should also hear 3 beeps, do NOT turn the key off, press and hold the light button down, and watch the hr meter display in the LH panel.
it should change from the hr display to a 4 digit number. that number is the fault code.
once you turn the key off, it clears from the display, and stores in the memory of the bobcat controller, (unreadable except with bobcat's service software)
there may be a small booklet behind the seat, you can look up the 4 digit fault code, it may lead you in the right direction for diagnosis.

:drinkup

 

[steve(ill)]

Talked to the #1 son tonight. He is still working and no chance or running the tractor till weekend... BUT, he did say the when things lock up , one of the three lights comes on and he hears 3 beeps. I though he said the light had a triangle like a general alarm light... I told him about the light button and read code on the hour meter... will try that this weekend. Thanks for the patience !

 

[willie59]

Steve, when the machine is in operation, and the BICS has no issues, all 4 LED lights on the BICS panel are lit. If you have a fault, say with the traction lock circuit, the traction lock LED on the BICS panel will flash and you'll here the 3 beeps. The beeps are an audible alarm to notify you there is a fault, and the BICS LED that is flashing is the circuit that has the fault. At that point, like crewchief said, don't touch nothing, don't raise the seat bar, don't shut the machine down. Instead, right then, push and hold down the work light button, this will bring up the fault code(s) in the hour meter display.

 

[steve(ill)]

OK, he told me he started the tractor last night and it was locked up immediately. He had 3 lights on above the key, not 4. HE had the one light on the other side and the 3 beeps. HE pushed the button and the code is 06-13.

Like I said, he could not move the machine, it was locked up as soon as he started the motor. I hope I am explaining this o.k. second hand.

 

[steve(ill)]

the three lights are on the dash above the hour meter. 1-2-3 from the left. The 4th light (right) is off.

Up above by the key is the trouble lite that stays lite and he has 3 beeps. code 06-13

 

[steve(ill)]

OK, I went to try the tractor myself so I could explain better what is happening...

I sat in the seat and pulled down the safety bar.
I turned the key to the first position and all 4 light on the upper left dash lit up for 1 second
The 1-3-4 lights then went out and only #2 is lit.
I started the motor and the 1-2-3 lights lit up, but traction lite does nothing.
I got a red diamond light in the upper right corner and the 3 dings sounded.
There is a red toggle "brake lock" switch dead center in front of your forehead. It was on. Son said if you turn it on - off you should hear a solenoid click. We hear nothing.
Bumped the travel levers forward and you can feel the tractor want to move, but it stalls down. Sounds like oil is dead headed against something.
Son has cleaned all the terminals, checked several lines to see if there is "crud" inside, cleaned filters.... so far no successs.
I think there is a "traction lock" toggle switch on the left side ? You toggle that and still nothing happens.

 

[willie59]

4th BICS panel LED from the left is the traction lock. Code 06-13 is no signal from engine speed sensor. I can't say specifically if that's what's causing your traction lock problem, but no signal from the engine speed sensor can make the ECU do some weird things.

 

[willie59]

We need to make sure we're on the same page steve. When you turn on ignition (not start) all 4 BICS lights flash as a self test. Start engine, no LED lights should be on. Drop seat bar, LED #2 should come on. Push the button marked "press to operate loader" and LED #1, 2, and 4 should now come on. If #4 doesn't come on, instead it flashes, and you get beeps, with code 06-13, you have a problem with the engine speed sensor. According to the manual the ECU won't allow the traction lock off if there's no input from the engine speed sensor.

BTW, you may not hear an audible "click" of the traction lock on a T190. Unlike the wheel loaders that uses a solenoid that makes a click noise, the solenoid valve that controls the traction lock on a T190 is much less audible.

 

[steve(ill)]

we are close willie--- all happens as you say, but I don't get #4 light to flash... it lights up during the initial test, but don't flash after startup....... 06-13 no engine speed (ort low)... maybe that wont let the brakes back off because it don't see the motor running at adequate speed ??? You know where the speed sensor is ? Will pull it and check wires / continuity. Can I bypass it or hot wire to run a test and see if that's the problem, or do you suggest a new sensor ? Should I get voltage or continuity at the wires on the sensor ? Resistance on the sensor ? What kind of test ?

 

[willie59]

The speed sensor is mounted into the flywheel housing just above the starter. I don't know that there's a way to test the sensor, the manual doesn't give any procedure, probably some form of variable reluctance resistor, doubt it's Hall Effect, but I don't know. Unless crewchief has some advice, only thing I could think to do is replace the sensor if you don't find wiring problems.

If you do replace the sensor, the new ones come with a plastic tip on them. Screw the new sensor into the flywheel housing until the plastic tip touches flywheel, lock down the jam nut. The plastic tip is designed to snap off when engine is started. This gives you the proper gap between sensor and flywheel.

 

[steve(ill)]

Thanks willie.... this sounds like a real good possibility.. Code says low engine speed and I can understand that brakes should be engaged until engine speed is adequate to get hydraulic power. I will look at the sensor / wiring / then consider a new sensor if all else looks good........ thanks for a step in the right direction.

 

[steve(ill)]

By the time I got message to son he had switched the two solenoids and ran a test... no difference. He was in the process of pulling the two solenoid spools when I gave him the message. The cleaned both hydraulic spools and cleaned the wire connector on the RPM pickup. The brakes started working, but the bucket cylinders did not. Thought he might have it narrowed down to the two hydraulic valves. Took both apart and polished and cleaned and reassembled. Tractor ran for 2 hours and locked up again........... Getting close.. has it narrowed down to sticky hydraulic spools, or intermittent RPM pickup. Did not check the codes this last time...... I think he can take it from here and finish repairs.

 

[steve(ill)]

I talked him into pulling the speed sensor out of the motor. It had crud/ rust growing on the probe end. Cleaned it up and reinstalled this morning and he rad a couple hours since then.. Thanks Willie / crewchief ... I think we got this !