Kubota LB552 loader weak lifting

[rrogers]

I have a Kubota L4300 w/ LB552 loader. It only has 100 hrs on it and once lifted just about anything I needed without problem. Now it seems to have problems lifting even a round bale more than a foot or two.

I blew off a line a few years back pulling fence posts and working it pretty hard. I replaced the line and added fluid, although it wasn't the Kubota fluid. Just the generic from Tractor Supply. It worked fine after that but seems to be getting continually weaker. The lift capacity on this loader is 1300-1700 lbs but I'm getting nothing close to that. All other hydraulics(3 point, etc) work fine and the fluid level is good. Surely the pump isn't going bad at 100 hrs or did adding the generic fluid hurt it? Any advice would ba appreciated.

 

[kennyd]

Welcome to TBN

-Have you ever done a complete fluid change-including filters and cleaning the suction screen?
-Does it sound like it's trying to lift? (engine lugging, squealing noises)
-It may be worth getting a gauge (one can be put together for about $35.00) and testing your PRV (pressure relief valve) pressure.

 

[rrogers]

Since it only has 100 hrs on it and it takes 41 qts to replace I have not tried that. However, I thought I might try a filter change first. Where would I look for the screen so I can replace it too? It's not in the owners manual. Thanks.

 

[kennyd]

The first fluid change is usually scheduled at 50 hrs to get casting and machining debris out of the transmission....can't help with the screen location.

Even though it has low hours, you still should be changing fluids on a regular basis. You stated "several years"...how old is that fluid!

 

[Duff]

Since you say all other hydraulics is working ok, and it only effects your lift.

Then I would:

1/ check that your linkage for the boom lift has a full free movement. Make sure your control valve for this function moves its full travel. If need be, take the linkage off the valve, and it must be very easy to move, if not get some WD40 on it to free it up.

2/ Check your quick disconnect couplings are fully in. Have a quick look at all your hoses to make sure there is no kinks/ squashed etc.

3/ Im suspecting one of your lift cylinder piston rings have had it.
Drive your tractor and place your bucket under a very heavy load that it will not lift. Such has big tree. Now try lifting it up under full revs. Your bucket is not to move! If it does, reposition your bucket or find somewhere else so it doesnt.
Once your bucket does not move, turn tractor off and remove the rod end hoses ( if you can, blank the hoses off ).
Now start the tractor and try to lift boom up under full revs.
There should be no oil that comes out of the oil port of the rod end of the cylinder. If oil comes out of one cylinder then remove that cylinder and replace the piston seals, or if both leak, then do both.


Best of luck

Duff

 

[heylloyd]

If you have the manual for the LB552 loader, look on page 12 under "Hydraulic Lines" and you will find a picture of the hydraulic block which has what looks like a screw head in the middle top portion. This screw head must be oriented with the slot vertical for proper operation. Unfortunately, it is in a position where it can come in contact with brush and the like which can turn it slightly off the vertical. The further from vertical the worse the operation.

If you don't have the manual, look under the foot board on the right side of the tractor next to the hydraulic filter and you will find this hydraulic block right there. Good luck from the only town in Texas with Frost on the water tower 365 days a year.

 

[kennyd]

If you have the manual for the LB552 loader, look on page 12 under "Hydraulic Lines" and you will find a picture of the hydraulic block which has what looks like a screw head in the middle top portion. This screw head must be oriented with the slot vertical for proper operation. Unfortunately, it is in a position where it can come in contact with brush and the like which can turn it slightly off the vertical. The further from vertical the worse the operation.

If you don't have the manual, look under the foot board on the right side of the tractor next to the hydraulic filter and you will find this hydraulic block right there. Good luck from the only town in Texas with Frost on the water tower 365 days a year.

Welcome, but please realize this is a 4+ year old thread that you replied to. Hopefully he got it fixed by now!