287B Hydraulics bogging engine

[Blacksmoke300]

Hello,
I have a 2006 Cat 287B XPS High Flow I recently picked up. It has roughly 2600 hrs on it. I'm having a hydraulic issue that bogs down the engine to a stall at idle when I go to feather the right joystick that controls the lift/tilt function. If I push it the joystick quickly for quick movement of the lift/tilt function it does not bog the motor and operates as it should. I have noticed it's mostly when trying to slowly drop arms or tilt back bucket when fine tuning grade. Another thing I have noticed is when you pick the arms up and let off, the arms slowly creep down. If you drop the arms down, it slowly creeps up. I have checked for sticking pilot buttons and all are moving freely. Any help on what else to check would be greatly appreciated.

 

[Mark250]

hi, serial number, recent history ,i.e. service ,repairs, after market attachments
Mark

 

[Blacksmoke300]

Hello Mark,
Currently not at the machine so I don't have the serial number. The machine had sat for 2-3 years with a issue that the right joystick did not function so there was no operation of the arms, it did however start and drive. It was believed to be a electrical issue but couldn't be found. I bought the machine after they gave up and found the problem to be corroded and rotted out ecms that were packed in dirt in the belly of the machine. Replaced both the interlock and hydraulic ecm and now both joysticks function. I have changed the hydraulic oil and filter, checked the pilot buttons underneath the joystick, and turned the relief valve screw in to tighten the spring for the lift relief valve but so far has not helped with the right joystick issue. I have only put about 4 hours on the machine since having the work tool joystick functioning for the first time in years so i believe something could possibly be stuck or sticking? Again the issue I'm having is only when trying to feather the right joystick to drop the arms or curl the bucket back it's bogging the motor to the point where I could stall it out. If I push the joystick all the way to do any function it doesn't bog the engine at all. Inter-related to that issue is if I raise the arms, they creep down. Drop the arms and they creep up. I've noticed there to be a ticking sound that sounds like it's coming from the rear of the machine if you raise the arms and turn off the machine.
I appreciate any insight you might have on what could be my problem and your time.
Thanks in advance,
Dominic.

 

[f311fr1]

The ticking could be a leaking load check in the main hydraulic valve.

 

[Blacksmoke300]

Do you think that could be related to why it's bogging the motor down at idle when retracting hydraulic cylinders? (Moving arm down and curling back bucket)

 

[f311fr1]

Possible. Have you looked and listened to the valve bank while some one else runs the machine. A heat gun while doing this might help you locate a hot spot (internal leakage).

 

[Mark250]

serial number MSH or ZSA
Have you checked pilot pressure (charge pressure) ?
Have you checked margin pressure?

 

[catman13]

I have a 289c and it will stall the motor at an idle when you run the hydraulics . talked to Cat and found out that standard on this model , raise the rpm just a little and it is fine,
that might be the same on that model

 

[Tyler Mofield]

wondering if anybody found a fix to this issue. I have a 287b with the same problem