Bobcat S590 Aux problems with attachment

[anybodii]

To start its a 2014 Bobcat s590 with 3500 hours, however, hydraulic components have almost all been completely replaced by a bobcat dealer. The bobcat functions and operates completely fine and at correct temps/pressure for driving, hauling dirt, etc. The problem: I only have one attachment that uses the aux its a fronthoe attachment. When I connect it to the aux and turn the aux on it instantly starts causing issues with the entire hydraulic system, I can hear and feel the pump going on/off if I try to drive or operate the boom it acts erratic such as I tell it to go up just a bit and it goes way up or slams down, the front hoe will move in and out if I touch its controls. What I've tried 1) Changed the hydraulic lines on the front hoe attachment 2) Replaced the cylinder on the front hoe attachment 3) Swapped the lines connected onto the cylinder of the front hoe attachment 4) Thinking possibly air in the lines I've rapidly moved the front hoe in and out I'm now thinking its likely not the fronthoe, but something in the aux system on the bobcat itself. Is there some sort of relief valve or something else specifically for the aux? Or anyone else have any ideas what to check or try?

 

[Tazza]

That's weird, does it do it when you have the revs down low too?
Wondering if the flow was too high causing it to go over the relief, messing with your other functions.

 

[7LBSSMALLIE]

I SUSPECT IT AN ISSUE WITH AUX COUPLER BLOCK , EASY DIGANOSE DEAD HEAD AUX IN ONE DIRECTION WARM OIL, IS LITTLE LINE GETTING HOT, YOU CAN FEEL IT WITH YOURE HAND, IT SHOULD NOT BE UNLESS YOU HAVE A HI FLOW ATTACH,HOOKED UP 3 LINES NOT TWO. IF SO AS IN LITTLE LINE GETTING HOT. INTERNAL LEAK AT C.OUPLER BLOCK. SO TO BE CLEAR NO ATTACHMENT TURN AUX ON FULL THROTTLE PULL TRIGGER, CHEC TEMPS AT AUX LINES IF LITTLE ONE HOT INTERNAL LEAK AT BLOCK, GOT TO THROUGH THIS IN THERE FLUID GOING OVER RESTRICTION CREATES HEAT, HEAT MEANS BYPASS, LIKE GOING OVER RELIEF RELIEF IS GOOD. LIMITS OVERPRESSURE, BUT THE CAN WEAR OUT OR STICK. SO ENDS THE LECTURE SORRY, GETTING OLD WANT TO TEACH

 

[7LBSSMALLIE]

I SUSPECT IT AN ISSUE WITH AUX COUPLER BLOCK , EASY DIGANOSE DEAD HEAD AUX IN ONE DIRECTION WARM OIL, IS LITTLE LINE GETTING HOT, YOU CAN FEEL IT WITH YOURE HAND, IT SHOULD NOT BE UNLESS YOU HAVE A HI FLOW ATTACH,HOOKED UP 3 LINES NOT TWO. IF SO AS IN LITTLE LINE GETTING HOT. INTERNAL LEAK AT C.OUPLER BLOCK. SO TO BE CLEAR NO ATTACHMENT TURN AUX ON FULL THROTTLE PULL TRIGGER, CHEC TEMPS AT AUX LINES IF LITTLE ONE HOT INTERNAL LEAK AT BLOCK, GOT TO THROUGH THIS IN THERE FLUID GOING OVER RESTRICTION CREATES HEAT, HEAT MEANS BYPASS, LIKE GOING OVER RELIEF RELIEF IS GOOD. LIMITS OVERPRESSURE, BUT THE CAN WEAR OUT OR STICK. SO ENDS THE LECTURE SORRY, GETTING OLD WANT TO TEACH

FULL THROTTLE TURN ON AUX DEADHEAD, WARM HYDS UP LITTLE LINE OR MALE QD LINE SHOULD BE COLD.,

 

[anybodii]

FULL THROTTLE TURN ON AUX DEADHEAD, WARM HYDS UP LITTLE LINE OR MALE QD LINE SHOULD BE COLD.,

Thank you for the replies guys, sorry didn't have it set to email when I got a reply. I ended up taking it to the dealer to diagnosis since they have fancy computers to read codes ( diagnosing is free from my dealer ) He said its actually a problem with the right lever ( I have lever/foot controls ) where the aux control button is on. Said $300 for the handle, 2 hours labor. Figured I'd update in case anyone else has this issue.