L2250 Kubota 3 point hitch cannot lift any weight

[ruffdog]

It sure sounds like a relief valve is free flowing and there is just enough pressure to lift the bare arms.

 

[djs l2250]

Hi Alex, no I said I checked the hydraulic delivery tube to the three point and checked for flow not at the PTO. Yes there is a pressure relief both in the 3 point and in the hydraulic block. I have had both of them out and replaced 0rings. I have the recommended pressure at the FEL 2375PSI Max but don't have the adapters to check the pressure at the 3 point. I agree, sounds like a pressure problem. One thing I'm not sure of is "if" I need a power beyond (PB) sleeve in my FEL Controller and if it makes a

difference where the two returns run back to the block are directed? ie does the PB line run to the front of the block return or to the "IN" on the front side port.

 

[Kernopelli]

Im not sure how similar the L2250 is to the L2350 but here is a link to operator's and parts manuals for the L2350. A parts manual can be very helpful in figuring out issues if you don't have a workshop manual.

Index of Kubotabooks/

 

[ptsg]

Hi Alex, no I said I checked the hydraulic delivery tube to the three point and checked for flow not at the PTO. Yes there is a pressure relief both in the 3 point and in the hydraulic block. I have had both of them out and replaced 0rings. I have the recommended pressure at the FEL 2375PSI Max but don't have the adapters to check the pressure at the 3 point. I agree, sounds like a pressure problem. One thing I'm not sure of is "if" I need a power beyond (PB) sleeve in my FEL Controller and if it makes aView attachment 786810 difference where the two returns run back to the block are directed? ie does the PB line run to the front of the block return or to the "IN" on the front side port.

So the flow goes from Out (#1) on the hydraulic block to the IN port of the hydraulic valve. From the hydraulic valve, the flow comes out the PB port with the PB sleeve and goes on IN (#4) on the hydraulic block. The Tank line from the valve goes to Tank port (#2) on the hydraulic block.

Having the Tank and PB lines reversed, can cause the symptoms you're experiencing. An easy way to check this is to try to lift some weight with the 3 pt, while lifting or curling the bucket at the same time.

 

[djs l2250]

So the flow goes from Out (#1) on the hydraulic block to the IN port of the hydraulic valve. From the hydraulic valve, the flow comes out the PB port with the PB sleeve and goes on IN (#4) on the hydraulic block. The Tank line from the valve goes to Tank port (#2) on the hydraulic block.

Having the Tank and PB lines reversed, can cause the symptoms you're experiencing. An easy way to check this is to try to lift some weight with the 3 pt, while lifting or curling the bucket at the same time.

Thanks,I'll check that out. I'm pretty sure there is no PB sleeve on that port. It's just a step down sleeve. I'll do some checking tomorrow.

 

[ptsg]

Thanks,I'll check that out. I'm pretty sure there is no PB sleeve on that port. It's just a step down sleeve. I'll do some checking tomorrow.

PB sleeve looks like this but since half of it is hidden inside the valve, it may give a false impression of a step down sleeve.

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[djs l2250]

If you have your 3pt arms up and then stand on them, do they hold your weight?

Yes

 

[ruffdog]

Yes

You would think that the lift cylinder and supply line would not be leaking. It has to be in the valve or pressure supplying the valve. A simple thing like a broken or misplaced spring etc would make the valve leak by and not supply pressure to the cylinder.

 

[djs l2250]

Ruffdog, I have ordered the PB plug from Summit Hydraulics. I'm going to install it which will disconnect it from the hydraulic block, Then I will connect the line for a closed center system hoping this will correct my pressure problem to the 3 point hitch. Thanks Dennis

 

[djs l2250]

Solved!!!!!!
I had a feeling when my joystick controller for my bucket was installed it was causing my 3 point hitch problems and I have found that it was. There was not an appropriate Power Beyond PB sleeve installed in my bucket controller so an appropriate amount of pressure was not being returned to the hydraulic block to run the 3 point hitch--regardless of the spool valve position. I completely removed the auxiliary 2 way valve that was attached. I installed a PB Plug designed for this bucket controller and removed the line to the # 2 port and blocked the #2 return port on the hydraulic block. Then I ran the tank line from the controller to the # 4 port on the block. The 3 point hitch now works perfectly. So not being an expert on hydraulics I believe my problem all along was the PB port had the wrong sleeve and/or block in it to allow the block to supply pressure to the 3 point. Hope all can follow my explanation and thanks again Wolfman for the help! Dennis ( I can supply pictures if it helps anyone, ) Also, shout out to SUMMIT HYDRAULICS for helping me find the correct PB plug for my bucket controller valve.