853 Wheel Lock Problem

[barnyardman]

I have a Bobcat 853 that when the bucket is raised about two thirds the way up the brake will lock and traction light will flicker on & off. You can raise, lower & tilt bucket, but won't move until you shut the machine off & let it reset. Thanks

 

[antfarmer2]

Sounds like a bad or loose connection.......maby a weak or craped up solinoid

 

[antfarmer2]

Sounds like a bad or loose connection.......maby a weak or craped up solinoid

Try pulling and swaping relays and fuses make sure they are clean

 

[antfarmer2]

Try pulling and swaping relays and fuses make sure they are clean

Check and clean seat and seat belt switch

 

[barnyardman]

Check and clean seat and seat belt switch

Thanks for the reply. The seat switch has been unhooked because of a replacement seat. What I don't under stand is I can use it all day long with no problem unless I raise the bucket bucket about 2/3 the way up and it locks the wheels

 

[koko3052]

Thanks for the reply. The seat switch has been unhooked because of a replacement seat. What I don't under stand is I can use it all day long with no problem unless I raise the bucket bucket about 2/3 the way up and it locks the wheels

Sounds like the wiring is being "strained" when the bucket goes that far up! I'll have a look at mine to see if any wiring is attached to the lift arms… but I don't think so.

 

[barnyardman]

Sounds like the wiring is being "strained" when the bucket goes that far up! I'll have a look at mine to see if any wiring is attached to the lift arms… but I don't think so.

Is there a lift sensor?

 

[Tazza]

Is there a lift sensor?

An OEM machine has no lift sensor, it's not low on oil is it? not that i can see that causing teh brake to engage....
I like the idea of straining wiring, but i can't think of any wiring that would be moved that could do this....

 

[OldMachinist]

Is there a lift sensor?

Definitely is a strange problem. A couple of things I can think of to cause it would be something with the brake pedal or the wiring to it is being moved when you push the lift pedal or the hoses that go up to the lift cylinder on the left side are rubbing/pushing the wiring behind the fuse/relay panel.
You can lift the cab and disconnect the brake switch wiring connector where it comes out of the protective steel tubing and see if it acts normal.

 

[barnyardman]

Definitely is a strange problem. A couple of things I can think of to cause it would be something with the brake pedal or the wiring to it is being moved when you push the lift pedal or the hoses that go up to the lift cylinder on the left side are rubbing/pushing the wiring behind the fuse/relay panel.
You can lift the cab and disconnect the brake switch wiring connector where it comes out of the protective steel tubing and see if it acts normal.

Thanks I will try that this week end and report back.

 

[jerry]

Thanks I will try that this week end and report back.

Didn't some of those models have auto bucket positioning controlled by solenoid? If so might be some of that wiring involved.

 

[barnyardman]

I noticed this weekend that it was worse when I first started using the machine. Unhooked brake switch and made no difference, but did not have time to trace the wires. Hydraulic fluid is full. Is it possible that the brake solenoid is the problem? Not sure how to test that. Thanks for any help

 

[Tazza]

I noticed this weekend that it was worse when I first started using the machine. Unhooked brake switch and made no difference, but did not have time to trace the wires. Hydraulic fluid is full. Is it possible that the brake solenoid is the problem? Not sure how to test that. Thanks for any help

It could be the solenoid failing or a bad relay. Hard to know for sure though.

 

[barnyardman]

PROBLEM SOLVED. First of all I want to thank every one for their input. The problem was the hose for the lift arm cylinder was real close to the brake relay and some times it would rub against the plug on the relay. Relocating the relay was the easiest thing to do. no problems since then Thanks very much for every ones help

 

[reaperman]

PROBLEM SOLVED. First of all I want to thank every one for their input. The problem was the hose for the lift arm cylinder was real close to the brake relay and some times it would rub against the plug on the relay. Relocating the relay was the easiest thing to do. no problems since then Thanks very much for every ones help

Thanks for posting the issue, it will come in handy for someone, someday. I'm happy to see it wasnt an expensive fix.

 

[Tazza]

Thanks for posting the issue, it will come in handy for someone, someday. I'm happy to see it wasnt an expensive fix.

Nice catch, at least now it's sorted out.