sticky 753 parking brake

[bobcat753]

Basically what the subject title states. Most of the time if I play with the seat bar or the flipper on the floor after a few trys it will release. Sometimes I have to shut it down and restart it. Is there anyway to fix this? Thanks, Ryan

 

[skidsteer.ca]

Sounds like a bad relay, just like a bad starter solinoid. You hit the key but nothing, try it 5 times and it finally makes contact. The relays are back in the engine compartment wth the fuses, Swap the park brake one for the glow plugs and see what happens.
Ken

 

[bobcat753]

Sounds like a bad relay, just like a bad starter solinoid. You hit the key but nothing, try it 5 times and it finally makes contact. The relays are back in the engine compartment wth the fuses, Swap the park brake one for the glow plugs and see what happens.
Ken

Just an update on this one, Now it will happen when I'm in motion. Its scary as hell I'll be driving along full tilt and the thing will lock up on me, almost flipping the machine. I've also noticed the traction light is now blinking 3 times and according to my manual that means Traction Lock hold coil circuit shorted to ground. Does anyone know what this means? I have to turn off the machine and restart it to get the code to go away. Could it be the symptoms of a bad brake solenoid?? I plan on switching the relays today once it stops snowing to see if that will change anything. Ryan

 

[Tazza]

Just an update on this one, Now it will happen when I'm in motion. Its scary as hell I'll be driving along full tilt and the thing will lock up on me, almost flipping the machine. I've also noticed the traction light is now blinking 3 times and according to my manual that means Traction Lock hold coil circuit shorted to ground. Does anyone know what this means? I have to turn off the machine and restart it to get the code to go away. Could it be the symptoms of a bad brake solenoid?? I plan on switching the relays today once it stops snowing to see if that will change anything. Ryan

Yes, it could be a bad coil. I can imagine it putting the machine on 2 wheels!

 

[bobcat753]

Yes, it could be a bad coil. I can imagine it putting the machine on 2 wheels!

Awesome good to know. Someone told me if you simply unplugged the sensor and tried it you can eliminate it that way? I tried doing that with the seat sensor and the brake solonoid, didnt seem to do anything, still had problems. Tazza when you flip the cab that sensor is located right under where the seat would be with 3 wires coming from it?

 

[Tazza]

Awesome good to know. Someone told me if you simply unplugged the sensor and tried it you can eliminate it that way? I tried doing that with the seat sensor and the brake solonoid, didnt seem to do anything, still had problems. Tazza when you flip the cab that sensor is located right under where the seat would be with 3 wires coming from it?

Thats the sender yes, but you can't simply bridge it. If your seat is rusted out you can install a bolt to pull it down so it thinks you are sitting in the seat at all times. You should be able to look at your BICS box and see if the light is lit or not, when its not lit it thinks you are not in the seat.
Simply removing the sensor will not work, it needs to think you are in the seat.

 

[bobcat753]

Thats the sender yes, but you can't simply bridge it. If your seat is rusted out you can install a bolt to pull it down so it thinks you are sitting in the seat at all times. You should be able to look at your BICS box and see if the light is lit or not, when its not lit it thinks you are not in the seat.
Simply removing the sensor will not work, it needs to think you are in the seat.

Thanks for the info, I think Im gonna try to fool the seat bar and seat sensors to see if that will fix my problem. Is there a way to fool the parking brake to test?? If none of this works I'll have to buy the brake solenoid or take the machine into the shop. Now if it would just stop snowing, I'd get right at it!

 

[Tazza]

Thanks for the info, I think Im gonna try to fool the seat bar and seat sensors to see if that will fix my problem. Is there a way to fool the parking brake to test?? If none of this works I'll have to buy the brake solenoid or take the machine into the shop. Now if it would just stop snowing, I'd get right at it!

You can, my 751 i'm working on STILL i took the sensors off and the magnets too. I have them hanging in place using tape to hold the magnets in the rite spots to fool the sensor into thinking everything is rite. You should be able to do the same to test it out. When the light on the BICS box is lit the sensor thinks its all good.

 

[mrfixitpaul]

You can, my 751 i'm working on STILL i took the sensors off and the magnets too. I have them hanging in place using tape to hold the magnets in the rite spots to fool the sensor into thinking everything is rite. You should be able to do the same to test it out. When the light on the BICS box is lit the sensor thinks its all good.

I've replaced the brake solenoids on several machines over the years due to them 'shorting out' , sometimes only when they got hot. Very rarely is it the relay but check the wiring to make sure it isn't rubbing somewhere. When it's apart to change the solenoid make sure that the 1/4 inch bolt that holds the plunger to the lock isn't grooved or you'll still have troubles, and make sure the 4 bolts with 3/4 heads are tight to prevent binding. As far as the seat and seatbar sensors....the magnet causes a change in resistance in the circuit when in the correct position....you can't just disconnect or jump the wires to bypass either one.

 

[bobcat753]

I've replaced the brake solenoids on several machines over the years due to them 'shorting out' , sometimes only when they got hot. Very rarely is it the relay but check the wiring to make sure it isn't rubbing somewhere. When it's apart to change the solenoid make sure that the 1/4 inch bolt that holds the plunger to the lock isn't grooved or you'll still have troubles, and make sure the 4 bolts with 3/4 heads are tight to prevent binding. As far as the seat and seatbar sensors....the magnet causes a change in resistance in the circuit when in the correct position....you can't just disconnect or jump the wires to bypass either one.

Paul thanks for the advice, I'm starting to think your right on the brake solenoid being the culprit. Today I did the following: 1. Unhooked the seat bar sensor and taped the magnet in the proper location. I think I'm gonna leave it this way! Plan on doing this to the seat sensor as well. 2. Went through all the fuses, added dialectric grease and installed all new fuses. 3. Rotated all the relays around. 4. Checked the wires under the cab yesterday and they looked good. Where I'm at now is it will not move at all. All the lights on the BIC will light up like its ready to go but its still locked. I'll try to move fwd and back a few times and then the traction light will start to blink 3 times. Problem is now I'm half in the garage, half out. Gonna have to hook up my truck and drag it out so I can flip the cab. Is there any point in pulling the solenoid out and taking the wedge out to test it? If I did order one its gonna take a week for me to get it.

 

[skidsteer.ca]

Paul thanks for the advice, I'm starting to think your right on the brake solenoid being the culprit. Today I did the following: 1. Unhooked the seat bar sensor and taped the magnet in the proper location. I think I'm gonna leave it this way! Plan on doing this to the seat sensor as well. 2. Went through all the fuses, added dialectric grease and installed all new fuses. 3. Rotated all the relays around. 4. Checked the wires under the cab yesterday and they looked good. Where I'm at now is it will not move at all. All the lights on the BIC will light up like its ready to go but its still locked. I'll try to move fwd and back a few times and then the traction light will start to blink 3 times. Problem is now I'm half in the garage, half out. Gonna have to hook up my truck and drag it out so I can flip the cab. Is there any point in pulling the solenoid out and taking the wedge out to test it? If I did order one its gonna take a week for me to get it.

Its easy to remove the wedge under the solinoid coil ,or just pull the rod up (after removeing the coil) and put a hose clamp on it to hold it there. Then you can move again. Not sure if you can glue the magnet on the seat bar sensor in place, I know you can with the seat on because it expects you to be seated when you turn the key on, however the seat bar one may be your trouble with the bics.
Ken

 

[bobcat753]

Its easy to remove the wedge under the solinoid coil ,or just pull the rod up (after removeing the coil) and put a hose clamp on it to hold it there. Then you can move again. Not sure if you can glue the magnet on the seat bar sensor in place, I know you can with the seat on because it expects you to be seated when you turn the key on, however the seat bar one may be your trouble with the bics.
Ken

Ken arn't the seat bar and seat sensors the same? If so I can just take the magnet, rotate it till the green light is on and tape it there?!? Looking in the service manual they look the same, I guess I'll find out tmrw.

 

[Tazza]

Ken arn't the seat bar and seat sensors the same? If so I can just take the magnet, rotate it till the green light is on and tape it there?!? Looking in the service manual they look the same, I guess I'll find out tmrw.

Ken - my BICS on the 751 doesn't care that i taped the seat bar magnet in place, same with the seat. The BICS operates just fine. Turn the key to the auto glow you hear a SNAP from the park break releasing then the light goes out saying its ready to start. Its never had a problem with fooling the BICS box, later BOSS machines may be different though......

 

[farmer]

Paul thanks for the advice, I'm starting to think your right on the brake solenoid being the culprit. Today I did the following: 1. Unhooked the seat bar sensor and taped the magnet in the proper location. I think I'm gonna leave it this way! Plan on doing this to the seat sensor as well. 2. Went through all the fuses, added dialectric grease and installed all new fuses. 3. Rotated all the relays around. 4. Checked the wires under the cab yesterday and they looked good. Where I'm at now is it will not move at all. All the lights on the BIC will light up like its ready to go but its still locked. I'll try to move fwd and back a few times and then the traction light will start to blink 3 times. Problem is now I'm half in the garage, half out. Gonna have to hook up my truck and drag it out so I can flip the cab. Is there any point in pulling the solenoid out and taking the wedge out to test it? If I did order one its gonna take a week for me to get it.

I have had the same problem with my 753, although it didn't stop me while I was moving. my problem seemed to be solved with bending the clips for the fuses a little tighter and new fuses also cleaned it all up with contact cleaner. The cover was missing so oil dirt etc was in there and made a bit of a mess.... That has been a month or so now and seems to work okay. I know how frustrating this is, hope it helps

 

[bobcat753]

I have had the same problem with my 753, although it didn't stop me while I was moving. my problem seemed to be solved with bending the clips for the fuses a little tighter and new fuses also cleaned it all up with contact cleaner. The cover was missing so oil dirt etc was in there and made a bit of a mess.... That has been a month or so now and seems to work okay. I know how frustrating this is, hope it helps

Farmer, I thought about that, but so thats why I went through it cleaned them and put new ones in. They all seemed pretty tight tho. Question tho. I just took the seat sensor apart and by using a bolt and two washers believed I've fooled it. Will it not start unless this sensor is activated??? After doing this It will start but I'm having the same problem. So now its the brake solonoid I'm gonna pull...

 

[bobcat753]

Farmer, I thought about that, but so thats why I went through it cleaned them and put new ones in. They all seemed pretty tight tho. Question tho. I just took the seat sensor apart and by using a bolt and two washers believed I've fooled it. Will it not start unless this sensor is activated??? After doing this It will start but I'm having the same problem. So now its the brake solonoid I'm gonna pull...

Well looks like you guys might be right, pulled the brake solenoid and it looks like it might have overheated. The cap where the wires go in is all distorted. So I'll be ordering one of those. Also looking at the parking brake, the tube that runs along the middle by your feet is loose, gonna pull it out and make sure the wires arn't rubbing while I'm at it.

 

[bobcat753]

Well looks like you guys might be right, pulled the brake solenoid and it looks like it might have overheated. The cap where the wires go in is all distorted. So I'll be ordering one of those. Also looking at the parking brake, the tube that runs along the middle by your feet is loose, gonna pull it out and make sure the wires arn't rubbing while I'm at it.

Just an update, so I changed the brake solenoid and everything works perfectly now. Also you have to keep the seat bar sensor there, if you don't you'll be able to drive the machine with the seat bar up/down. I was able to drive it in the garage by standing on the bobtach(not safe). All I have left to do now, is to weld the parking brake tube(in the middle by your feet), its loose. Plan on inspecting all the wires while I'm at it. Thanks for all the help guys.

 

[Tazza]

Just an update, so I changed the brake solenoid and everything works perfectly now. Also you have to keep the seat bar sensor there, if you don't you'll be able to drive the machine with the seat bar up/down. I was able to drive it in the garage by standing on the bobtach(not safe). All I have left to do now, is to weld the parking brake tube(in the middle by your feet), its loose. Plan on inspecting all the wires while I'm at it. Thanks for all the help guys.

Glad it was a *simple* fix, just a lot of work to work out what it was....

 

[bobcat753]

Glad it was a *simple* fix, just a lot of work to work out what it was....

It sure was lol Now is there anyway to get the wires outta the parking brake tube, other then cutting them and then connecting them back together? Don't want to weld the tube with the wires in it, might fry them....