Bucket will not curl

[djm1204]

My tractor is a 2014 L4600 with the LA765 loader

My problem is the bucket will not curl. When I activate the control, the bucket will curl forward, or downward, about ¼ of the way and stop. If I hold the control to the right to continue the curl, I can hear the pump trying, but the bucket does not go any further. When I release the control, the noise of the pump stops. When I move the control to the left, the bucket immediately curls backwards towards the tractor.

All other hydraulics work fine. The lifting up and down works fine, actually I have a grapple attached and all of it’s functions work fine, it is just the curling that is not working.

Trouble shooting, I checked that all connections are clean and tight. I checked that the rear 3 point hitch was not in the wrong position. Finally, I reversed the hydraulic lines that go to the cylinders that control the curling of the bucket. When I reversed the lines, the bucket would curl down 100% as it should, however now it would only curl back about ¼ of the way. When I return the hydraulic lines to the original connections, the original issue returns, I can only curl the bucket 1/4 of way forward.

So, before I spend a fortune at the stealers shop, is there anything else that I should/could check? I am not a master mechanic but can follow directions and turn a wrench.

Any help will be greatly appreciated !

Dan

 

[djm1204]

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[rentthis]

The first thing to re-check is your quick disconnects on the hoses. Those things will fool you. Break them loose and reconnect them. Sometimes the fittings will fail. Push on them really hard and see if that helps.

 

[100 td]

By swapping the lines you have proved the cylinder extends and retracts fully.
So it comes back to the valve body, does your valve body have auto level on it, could it be hampering the operation? Is your valve body controlled by cables, are they tight or binding? Can you physically see the spool valve and ensure it is operating full stroke? Does your valve have regen feature or detents that may be affecting/jamming the spool.
It sounds most likely a spool issue, with one of the above scenarios affecting it, stopping it from traveling or there is something jamming the spool.

 

[North Idaho Wolfman]

Swap the lines from lift to roll.
If the issue moves to the lift, it's a the quick disconnect on the valve side or worse the valve is bad.
If the issue stays with the roll you have an issue with the Quick connect on the line or a bad cylinder.

 

[Dave B.]

This just happened to our B3300SU - after tearing a hydraulic hose on FEL. Replaced the hose and lost the bucket curl - all other FEL functions worked well - cracked the oil lines leading to the bucket - no oil on the bucket return cylinder. Press in on the joystick to curl bucket back - audible sound of the pressure relief valve kicking in on the HST pump. Next replaced the hydraulic hose fitting attached to hard lines leaving the spool valve (the barbed fitting that the quick-connect hoses attach to when removing the loader arms)..turns out that when the hydraulic hose was originally torn - it shocked the pressurized side of the hydraulic lines...blew out an o-ring at the spool valve & also damaged the fixed barbed fitting...this was hard to troubleshoot as the spring-loaded center valve was still working. Removed the barbed fitting and looked inside with a bright flashlight the 3 spring-loaded arms that hold the fitting into the inner flange had blown out on all 3 contact points - when attaching the new hose to this barbed fitting - it was still pressurized, press in on the center valve after releasing pressure using the joystick functions - must have turned the 3 spring-loaded arms about 1/4 turn - so that they were once again seated on their inner flange - with 3 obvious blow outs in the flange...the broken flange pieces were jammed into the tip of the barbed fitting - which is why there was restricted (almost none) oil flow. The new barbed fitting only cost $8 at the hose shop - FEL curl function started working immediately without bleeding any additional air from the hydraulic system.