TRACTION LOCK

[DLR773]

I have a bobcat 773 the 25 amp brake fuse blew and the cat would not move . I replaced fuse and it blew again , started trying to figure out what was wrong . I did not find any bad wires are anything . Well replaced the traction lock solenoid and fuse and everything was fine . Went to work . WELL yesterday it happen again fuse blew and no movement . I open the cab and the solenoid smelled burnt I took it out so I could move the bobcat . ANY THOUGHTS ON WHY THIS MAY BE HAPPENING . I CANT BUY THESE SOLENIODS EVERY FEW WEEKS TO KEEP IT GOING. Anything else I should check I would love the input .. it does not have a seat sensor . THANKS

 

[SSdoxie]

The solenoid has 3 wires on it. 1 is ground, 1 is high amp 12v momentary pull to pull the stem up, and the other is low amp 12v to hold the solenoid in unlock position. The Pull circuit which has the 25 amp fuse and a relay on only supposed to be on for fraction of second the power is shut off. On F-series and older units the relay for this has a timer to cut the power, on G series and later it is done through the controller. I suspect the Pull circuit is not shutting OFF and the continued high amp will cook a solenoid very quickly. If your 773 requires engine to be running before brake will release be sure block all 4 wheels off the ground before attempting any voltage tests. A weak//poor ground can also overheat a solenoid but usually this will result in an intermittent brake lockup while operating.

PS. this should have been posted in Bobcat Construction Equipment not Tractor so see if you can get an Admin to move it for you.

 

[DLR773]

Thank you sir for your help . I am working on this problem today . Mine is an f-series where would I find this timer location ? I also have a fuse #6 for the PMW blown (whatever that is ) I am checking on this too , don't know if they are related or not . If you have anymore info I would to hear from you . Thank you Larry

 

[DLR773]

The solenoid has 3 wires on it. 1 is ground, 1 is high amp 12v momentary pull to pull the stem up, and the other is low amp 12v to hold the solenoid in unlock position. The Pull circuit which has the 25 amp fuse and a relay on only supposed to be on for fraction of second the power is shut off. On F-series and older units the relay for this has a timer to cut the power, on G series and later it is done through the controller. I suspect the Pull circuit is not shutting OFF and the continued high amp will cook a solenoid very quickly. If your 773 requires engine to be running before brake will release be sure block all 4 wheels off the ground before attempting any voltage tests. A weak//poor ground can also overheat a solenoid but usually this will result in an intermittent brake lockup while operating.

PS. this should have been posted in Bobcat Construction Equipment not Tractor so see if you can get an Admin to move it for you.

I am working on this I have a f-series 773 ser 509645966 . Can you tell me where this timer would be located ? I also found fuse #6 blown for the PMW (whatever that is ) any info on where this is located are what it is ? Thank You for your help
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