L245DT Hydraulic Problem

[kenan]

I have a Kubota L245DT. I just installed a Kubota Front End Loader. I used the original Kubota block located to the left of the seat. This block has 2 lines coming out going to the FEL control valves (mine has 2 levers). One line goes from the fill plug near the front of the seat to the FEL control valve. Three hydraulic lines total from the tractor to the FEL control valve.

My 3 point hitch lift worked great before I installed the FEL. The FEL works great but now my 3 point hitch lift will not work at all.

I assume I either have two of the lines switched OR there is a problem in the control valve for the FEL.

Does anyone have any ideas?

Thank you,
Kenan

 

[J_J]

This might be your problem. The three lines coming to the FEL should be pressure in to the FEL,and that seems to be connected correctly

A PB line going back to the block for the 3pt, and a return line. These two might be switched.

If the source for the 3pt is getting the FEL cyl OUT fluid, it would only get a little fluid while the cyl is moving.

That leaves the PB from the FEL valve. If it is going to the tank, then no fluid is available for the 3pt.

A hyd gage might help solve the problem.

 

[kenan]

J J,
I was hoping you would see this post! I am new to this forum but I already appreciate your knowledge about hydraulics.

I will try this this morning and let you know the results.

Thank you again for your input.

Kenan

 

[kenan]

JJ,
I hooked up a hydraulic gage like you suggested.
I now know what the problem is.
I do NOT know what the solution is.
My control valve is not factory Kubota.
The control valve is labeled with "IN" and "OUT" ports.
The pressure side from the tractor block is hooked into the "IN" port. The FEL works.
On the "OUT" side of the control valves, the return pressure to the tractor block for the 3 PH AND the bypass return to the gear case, come out of the same block.
The problem is that the block is completely open. There is no pressure on this side on either line, the fluid is dumping straight to the gear case.

I have temporaraly plugged one port.
I plugged the port that was going to the gear case.
Now I have pressure to the lift and the lift will work and the FEL works - EXCEPT if the 3 PH is fully raised and I raise the FEL, the FEL will not come back down until I lower the 3 PH. There is no bypass for the fluid.

What is missing? I do not know what to buy to fix this problem.
I have pictures of my block but I could not figure out how to attach them to this reply.

My e-mail is kenanweekend@yahoo.com
If you need to see the valve setup, send me an e-mail and I will reply with the pictures attached.

Thank you again for all of your input!

 

[J_J]

If you move the 3pt lever down from fully up, the 3pt valve should be in neutral, and the fluid should go to tank.

You did not say that you had PB out from the FEL. If you only have 6 hoses on the FEL valve you do not have PB.

If you only have two hoses from the FEL valve, then the hyd flow is from the tank port on the FEL. So if you pressurize the 3pt line, the cyl fluid from the FEL has no place to go, until you release the 3pt valve to neutral.

In most cases, the return/tank port goes to tank, but some manufacturers do the cheap route.

If you hold the 3pt lever up, the fluid will be relieved, but the line is still pressurized.

 

[J_J]

Your 3pt hitch work great before you installed the FEL, because the pump fed the 3pt valve directly and there was only one line from the pump to the 3pt valve. The relief valve in the 3pt valve regulated the pressure. If you raised the 3pt lever to the max, the valve relief, relieved the pressure, until you lowered it slightly to neutral.

Some tractors use a hyd block to route the fluid.

 

[kenan]

JJ,
I want to fix this correctly.

The block I have can be added too.

Can I add a Pressure Out block to the valve control block I have?

OR

Do I need to buy a new control valve setup with a Pressure Out port?

 

[J_J]

Best bet is for one of the Kubota guys to jump in here about that hyd block. The hyd block on my Kubota is a simple block with a small lever to select source and destination.

One hardly uses the FEL and 3pt at the same time, so it could work. Just make sure the 3pt is in neutral.

If you have the gage installed on the FEL valve where you can see it, then you will know when the lines are pressurized. With the gage installed, you can also check the relief pressures on the FEL and the 3pt.

If you wanted to, you could install a new joystick FEL valve with PB, float and regen on the bucket, for less than $300.

 

[kenan]

JJ,
Thank you. I think I will buy a new FEL block.

Do you have a supplier you recommend?

If not, thank you so much for the help.

 

[J_J]

Do you mean FEL valve. You should already have the hyd block/manifold.

This FEL valve is a 10 GPM valve with PB, float, regen.

Surplus Center - 2 SPOOL COMPACT 10 GPM JOYSTICK CONTROL VALVE

 

[kenan]

JJ,
I apologize for the delay. I have been away from e-mail.

Yes, the valve is what I meant.

I am going to buy one with the P B feature - like the one you sent me the link too.

Thank you again for helping me solve this problem.

Kenan

 

[J_J]

Before you order a new valve, send me pictures of your current valve with a clear view of all sides to my email.

Should you order a new valve, you can make up a valve mount for the old joystick valve and have a nice set of remotes on the rear of the tractor, for T-N-T maybe or some other attachment.

Fender might be a good place to mount the valve.

 

[kenan]

JJ,
I believe the photos are attached. This is the first time I have done an attachment in this forum.

I



Thank you,
Kenan

 

[J_J]

Thanks.

In the first picture, the large hex nut could be your PB out port. Can you take a wire brush and clean off that end of the valve and see if there are any markings, like PB, or PBY.

I see 7 hoses connected, but the large hex nut is in the right place for PB OUT.

The brand name of the valve if you can read it.

You are going to need some hoses now or in the near future.

 

[kenan]

I did take the hex nut out in the first picture. It is just an open cavity to both hoses connected into this block. The hex nut on the opposite side is open to the Pressure In hose. I cannot find a brand name on the valves.
I found out that this valve setup was purchased through Northern Hydraulics.
From my research on their web site, it appears this block did not come with a PB option and a PB option cannot be added to it.

The Kubota in the picture is the tractor I took the FEL off of. My tractor is in much better shape. I have already replaced all hydraulic hoses and rebuilt the cylinders.
Everything except the bucket & main boom has been sandblasted, zinc plated, and powder coated (I have some generous friends)!

Everything is working great except the PB option is missing. Thanks to you I now understand how it is supposed to work. I think my only way out is to buy a valve body with the PB option.

The weather has been nasty here, when it clears up I will take a picture of the tractor as it is now and send it to you. I still have to get the boom painted - I just could not wait any longer to play with it!