Bobcat 953 Skidsteer Bucket Won't Lower

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sauciechick

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Jun 26, 2018
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We bought a used Bobcat Skidsteer 953 that was leaking hydraulic fluid and the tilt wasn't holding. Took to a mechanic, who said the tilt valve was bad. Replaced the tilt valve, and the leak stopped but the tilt still didn't work. Rebuilt the hydraulic cylinders and everything worked on the drive around. Went to pick it up the next day and the bucket went up but would not lower, and there it sits. Any ideas? Thanks in advance.
 

bobbie-g

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Mar 15, 2004
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Serial number is 513111100. Checking if any error codes.
Unsure what you mean by bucket went up but wouldn't come down. Are you referring to the tilt, so that the bucket tilts upward but will not tilt downward? Or are you referring to the lift arms that went up but wouldn't come down? :) ---Bobbie-G
 
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sauciechick

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Unsure what you mean by bucket went up but wouldn't come down. Are you referring to the tilt, so that the bucket tilts upward but will not tilt downward? Or are you referring to the lift arms that went up but wouldn't come down? :) ---Bobbie-G
The tilt now longer works at all, and the lift arms went up but will not lower. Thank you
 

bobbie-g

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Thank you -any idea where to start looking for a fix?
OK, lemme offer some half-baked thoughts here, as I'm still a novice at Bobcats. First, I think the 900 series machines are fairly old, so probably not computer controlled, but we need to sort that out first. What do the upper left and upper right panels in the cab look like? Is there a module with about 5 green LEDs just behind the operator's right elbow? That will get us started with understanding how your machine is configured. --- The valves on the arms and bucket are "locked" by solenoids until the machine decides it's ready to work. If neither arms or bucket will move, then the solenoids are not releasing, most likely because the safety control mechanism hasn't told them to release. So somehow, the control mechanism probably thinks it's not OK to operate the machine. There is likely a seat switch and a lap bar switch. If either are not "engaging", then the control mechanism won't let the machine do anything. That would be a place to start looking to see if either of those may be preventing an unlock. BTW, since the arms won't move, sounds like the "parking brake" will be engaged also, so the machine probably won't move more than a few inches. --- So with some answers to the above, some of us can offer more advice. BTW, the hydraulic release Tom... mentioned is adjacent to the seat on the right hand side, about an inch to the right of the seat edge, right in the middle (front-to-back). Or maybe the knob got lost and it's just a 1/4" threaded stud sticking up an inch or so. If you pull up an inch or so and rotate it to the right, the hyd pressure will be released and the arms will come down. Be really careful to be out of the way, since there's no getting the arms back up. Also, if you will need to drag this machine anywhere, you may want to stop the arms before the bucket drags the ground. Good luck! :) ---Bobbie-G
 
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sauciechick

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Jun 26, 2018
Messages
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OK, lemme offer some half-baked thoughts here, as I'm still a novice at Bobcats. First, I think the 900 series machines are fairly old, so probably not computer controlled, but we need to sort that out first. What do the upper left and upper right panels in the cab look like? Is there a module with about 5 green LEDs just behind the operator's right elbow? That will get us started with understanding how your machine is configured. --- The valves on the arms and bucket are "locked" by solenoids until the machine decides it's ready to work. If neither arms or bucket will move, then the solenoids are not releasing, most likely because the safety control mechanism hasn't told them to release. So somehow, the control mechanism probably thinks it's not OK to operate the machine. There is likely a seat switch and a lap bar switch. If either are not "engaging", then the control mechanism won't let the machine do anything. That would be a place to start looking to see if either of those may be preventing an unlock. BTW, since the arms won't move, sounds like the "parking brake" will be engaged also, so the machine probably won't move more than a few inches. --- So with some answers to the above, some of us can offer more advice. BTW, the hydraulic release Tom... mentioned is adjacent to the seat on the right hand side, about an inch to the right of the seat edge, right in the middle (front-to-back). Or maybe the knob got lost and it's just a 1/4" threaded stud sticking up an inch or so. If you pull up an inch or so and rotate it to the right, the hyd pressure will be released and the arms will come down. Be really careful to be out of the way, since there's no getting the arms back up. Also, if you will need to drag this machine anywhere, you may want to stop the arms before the bucket drags the ground. Good luck! :) ---Bobbie-G
Thank you. It's a 1995, and does have the BICS control in the cab. I'm trying to find out what the lights are showing.
 

bobbie-g

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Thank you. It's a 1995, and does have the BICS control in the cab. I'm trying to find out what the lights are showing.
Five BICS lights: bottom one is power. Top one is seat switch, next one down is lap bar. Then valves, then traction. The seat switch gives folks problems, so that's a place to start, to make sure the seat LED is on. Lap bar switch seems to not give much trouble. But both of those LEDs must be illuminated before the BICS module will actuate the valve and traction solenoids. ---Bobbie-G
 

Tazza

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Five BICS lights: bottom one is power. Top one is seat switch, next one down is lap bar. Then valves, then traction. The seat switch gives folks problems, so that's a place to start, to make sure the seat LED is on. Lap bar switch seems to not give much trouble. But both of those LEDs must be illuminated before the BICS module will actuate the valve and traction solenoids. ---Bobbie-G
Bobbie-G is on the right path. The later model machines have a lockout solenoid for the lift section. All the BICS lights need to be lit for it to disengage, if they are all on and it still does not work, you may need to check your lockout solenoid. Lift the cab and look at the control block. There should be two solenoids, one at either end of the calve, this should be the aux hydraulics. If there is one on its own, that should be the lockout. Check it's getting power.
 
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sauciechick

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Jun 26, 2018
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Bobbie-G is on the right path. The later model machines have a lockout solenoid for the lift section. All the BICS lights need to be lit for it to disengage, if they are all on and it still does not work, you may need to check your lockout solenoid. Lift the cab and look at the control block. There should be two solenoids, one at either end of the calve, this should be the aux hydraulics. If there is one on its own, that should be the lockout. Check it's getting power.
Thanks Tazza and Bobby - were going to try these things out and I'll post back.
 
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sauciechick

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Jun 26, 2018
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Thanks Tazza and Bobby - were going to try these things out and I'll post back.
Wow - this is getting really frustrating! Machine started working properly. It set overnight and when the mechanic went to test it in this morning, it was back to the original problem, which is: Bucket arms are raising and lowering. Tilt will go up, but bleeds down (can hold it there with foot control). Pouring hydraulic fluid out of the tilt valve when in neutral. We have already replaced the tilt valve, and that replacement valve passed inspection.
 

bobbie-g

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Mar 15, 2004
Messages
577
Wow - this is getting really frustrating! Machine started working properly. It set overnight and when the mechanic went to test it in this morning, it was back to the original problem, which is: Bucket arms are raising and lowering. Tilt will go up, but bleeds down (can hold it there with foot control). Pouring hydraulic fluid out of the tilt valve when in neutral. We have already replaced the tilt valve, and that replacement valve passed inspection.
Sounds like two issues. One is the leaking valve, and the second is related to the BICS system. I have no experience with the valve leaking. With the BICS, my first thought is again to suspect the seat switch or lapbar switch. Try leaning into the cab and working the seat back back-and-forth while watching the BICS box to see if the seat switch LED comes on and off as is should. Same for the lapbar LED. Some folks fix the issue with the seat switch by relocating the switch and glueing the magnet in place; other will say that's not a good idea to bypass that protection. Up to you. Bobcat at one point sold a "bypass" switch assembly for the seat switch. In my case, I've just played with the switch mounting (under the operator's right thigh, forward bolt on the seat) and shimmed with washers till the switch worked OK when I was seated. It's a bit tricky to get it right. BTW, those use a magnetic switch and no one has yet figured out a way to remove the switch and jumper the three connector pins on the harness. :) ---Bobbie-G
 
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