Loader Loader won't hold position

[AlanLukes]

My dealer tells me that "all hydraulics slowly fall". Well, my loader won't hold at all - keeps slowly falling down; all the way down. A nuisance. Is this really normal? I've had other JD utility tractors and none of them behaved this way. Features of the new John Deere equipment???? Mine is a 2011 JD3320.

 

[J_J]

You should do a cyl test and see if the piston seals are bypassing.

 

[hokil3425081]

Cylinder Leak is two ( outside and inside )
it is inside leak, beacuse piston seal have some damaged.

cause 1 -> long useing
cause 2 -> inside metal chip ( production problem )
cause 3 -> poor seal ( production problem )
cause 4 -> Hydraulic oil probelm , worn out.


So, change piston seal.

 

[arlen4720]

how much does it leak down in inches per hour or minute?

 

[Wrenchin]

Does loader handle / to loader valve hard to move or is operations smooth? had one bind just enough to have hydro blow by.

 

[Wrenchin]

I've also had one wherey hyd_ro pioneer quick coupler at the valve for loader,the dent ball inside wasn't seating.

 

[AlanLukes]

Thanks, guys, for the good things to check. I'm afraid I'll have to bring it in to my favorite JD dealer as the issue appears to be in the hydraulic valve within the tractor. Symptoms are same if I mount the loader, broom, snowblower, etc. The fall rate is way too high per minute. The control lever inside the cab works nicely - free and seems to lock in all positions. But, probably a defective o-ring in there somewhere.

 

[oldnslo]

Alan,
Not to ruin your day but I doubt there are any O-rings in the control valve that would cause this leak down. Most hydraulic control valves are metal to metal seal via precise machined surfaces called lands. The spool is a sliding fit inside the casting with and the amount of clearance between the spool and the valve body bore along with the amount of overlap of the spool to the valve body land determines leakage rate.

If you have quick disconnects did you try swapping the lower and raise hoses? This would possibly help identify if the spool is not centering properly or one of the lands on the spool or body is damaged.

 

[arlen4720]

If you disconnect all the hoses, and it still leaks, then it's the cylinder. If it doesn't leak down, then it's leaking back through the valve.

 

[/pine]

just a thought...with the tractor off and the loader raised (and dropping) you might try just barely moving the joystick in the raise position and see if it has any effect on the leak down...

 

[kg7il]

just a thought...with the tractor off and the loader raised (and dropping) you might try just barely moving the joystick in the raise position and see if it has any effect on the leak down...

Excellent suggestion.

ALSO => check any other hydraulic control. ESPECIALLY the 3pt Control (lever for the valve that controls the lifting arms).

My Kubota Control lever has misaligned with the shaft and put it at the end of the travel and causes leak down and loss of power.

 

[AlanLukes]

Good suggestions. When I fire up the unit in a few days I'll do some experimenting. Good ideas from all of you. Thanks.