Hydraulic Drift Diagnosis

[flyguy79]

Hi guys - I'm new here, so not entirely sure this is the right place for this question, so please let me know if I should be posting it somewhere more appropriate. I recently purchased a 2011 Deere 319D for use around my property - cleaning up the woods, firewood, etc. - and have recently begun to notice hydraulic drift. The machine only had 202 original hours on it when I purchased it (had the dealer verify with the computer) and is incredibly clean - literally looks brand new. I know the previous owner took immaculate care of it, but it obviously didn't get much use.

The drift is most readily noticable in the bucket tilt. if you tilt the bucket all the way back, it VERY gradually - one creak at a time - drifts down maybe 20 percent of the way if left long enough. I have also noticed that the bucket breakout force doesn't quite seem to be what it was. Additionally, if I use the bucket / boom to lift the machine to check track tension, that also drifts slightly.

My question is this - there is clearly a ton of debate over internal seals leaking causing this (don't hardly think that's the case if the tilt and boom drift), and I don't know where to begin troubleshooting. I am very mechanical, but obviously no hydraulics technician. Any assistance you could offer would be greatly appreciated!

 

[RNeumann]

Is the machine running or not when this “drift” occurs? How fast is the drift occurring? All the way down in one minute, one hour, one day , one week etc?

 

[flyguy79]

Good evening, RNeumann. Thanks for the reply. It happens both when running and turned off. The bucket tilt will drift about 20 percent of the way down (particularly if loaded) inside a minute. it seems to slow if not stop at that. I have also noticed drift (3-4" in 15 minutes or so) when holding the machine up to check track tension. I also have a root grapple, and the grapple will drift down slightly over time if I run around for any length of time with it open. Does that help?

 

[CalG]

3-4" in fifteen minutes? Non issue.

Unless you just like chasing stuff.

Better is the mortal enemy of good enough.

 

[RNeumann]

I’d start by verifying their isn’t some air in the cylinder lines. Especially if it’s settling after a few inches of movement when loaded.

 

[kennyd]

Does the 319D have pilot operated controls?

 

[kennyd]

Is the machine running or not when this “drift” occurs? How fast is the drift occurring? All the way down in one minute, one hour, one day , one week etc?

Running or not makes no deference. When a valve is in neutral, the system can't keep pressure on or "add" pressure to keep a circuit from drifting...plus there is no sort of feedback system for the valve/pump to know something is drifting anyway.

 

[flyguy79]

Thanks for the response, KennyD. Yes, it does have pilot controls.

 

[flyguy79]

Hi CaIG. I certainly don稚 like chasing stuff - I hav three boys that scratch that itch... I do want to be sure something bigger is not going on though. The curious thing to me was the fact that bucket breakout force does not seem to be what it was when I first got the machine in October. It will barely curl out of a pile with a load of dirt - have to raise the boom first. Maybe that痴 normal, but it doesn稚 seem like it was that weak initially.

 

[flyguy79]

RNeumann - I値l certainly look at that. Is there typically a bleeder valve on each cylinder or is there a procedure for bleeding the whole system? I do have the maintenance manual and will check that. I知 leaving town for a couple of days but have the end of the week off to putter around with it.