L245Dt FEL front hydraulic pump and shaft problem

[Russell King]

I think your picture is deceptive in the way the gauge looks like it is in between the valve and the filter. When I zoom in, the filter is actually placed in a line that enters the valve on the left hand side. That would be the pressure in port of the valve and the output from the pump.

That port must be connected to the tractor’s hydraulic pump output. The port that has the filter attached must be connected to the other pipe going to the three point hitch. That port is generally called the power beyond port if there is a power beyond sleeve installed. In your case that is the tank return being used for high pressure carry over (I think I have the correct name.). That line is the input into the three point control valve.

Your pressure is good enough but I think the tractor pump will get to around 2000 PSI unless it is worn out.

I think you can find the Work Shop Manual (WSM) here

Index of Kubotabooks/Tractor Owners Manuals/

Added on edit:
@NIW has beat me to the answer again. BUT I don’t think you will be returning any fluid from the tractor pump to that existing FEL sump. I am assuming you intend to abandon the front mounted pump and switch to the tractor pump. The tractor pump draws out of the transmission through a mesh screen so would empty the tractor sump quickly and overflow the FEL sump. The tractor pump would run dry and become damaged.

 

[TheOldHokie]

Thanks, I'm slowly getting it. Attached is a picture of my current FEL valve. The supply line is where the pressure gauge is. The four lines are for the lift and tilt functions. So I could take the line that goes to the filter and connect it to the return port as shown on the previously posted hydraulic block diagram? I've previously thought of this as a lower pressure since it goes to filter on my tractor. The pressure at the gauge is 0 until the levers are operated and goes to 1,500 +/- .
What is the nominal pressure to the 3 point (control valve?) system from the pump?

This is an open center system. The pressure on both sides of the valve is "zero" when the valves are in the neutral (centered) position. When a valve is shifted pressure on the inlet side will increase to whatever is required to move the cylinders. The output side remains at "zero". The MAXIMUM pressure that the pump can create is determined by the relief valve setting in the loader valve.

To use the tractor hydraulics you would eliminate the filter and maximum pump pressure will still be determined by the relieve valve in the loader valve. But now the output side is supplying the 3pt and pressure can get as high as the inlet side which is why you have to eliminate the filter.

I think you will find replacing that old valve with one with joystick control is a win in and of itself and also cleans up the plumbing.

Dan

 

[Allegany Kubota]

I think your picture is deceptive in the way the gauge looks like it is in between the valve and the filter. When I zoom in, the filter is actually placed in a line that enters the valve on the left hand side. That would be the pressure in port of the valve and the output from the pump.

That port must be connected to the tractor’s hydraulic pump output. The port that has the filter attached must be connected to the other pipe going to the three point hitch. That port is generally called the power beyond port if there is a power beyond sleeve installed. In your case that is the tank return being used for high pressure carry over (I think I have the correct name.). That line is the input into the three point control valve.

Your pressure is good enough but I think the tractor pump will get to around 2000 PSI unless it is worn out.

I think you can find the Work Shop Manual (WSM) here

Index of Kubotabooks/Tractor Owners Manuals/

Added on edit:
@NIW has beat me to the answer again. BUT I don’t think you will be returning any fluid from the tractor pump to that existing FEL sump. I am assuming you intend to abandon the front mounted pump and switch to the tractor pump. The tractor pump draws out of the transmission through a mesh screen so would empty the tractor sump quickly and overflow the FEL sump. The tractor pump would run dry and become damaged.

Hi, attached is a better picture of the FEL valve. The guage was to be temporary while I investigated a performance issue (the loader would not lift the tractor front).
I understand the FEL input should be connected as line #4 in the attached diagram and the port that goes to the filter should be connected as line #7 in the diagram.
A few observations. I will be losing the FEL filter and reservoir. I'm currently using NAPA AW-46 for my hydraulics (loader and 3 point backhoe). The transmission fluid is at the full level but I do not know the type as I got it with the farm. The previous owner was knowledable so it is probably UDT or UTF as recommended. How would I flush the existing fluid in the loader to not contaminate the transmission?
Alternatively, could I connect unused Port #2 in the diagram to the FEL valve and run the return to the transmission reservior?

 

[TheOldHokie]

Alternatively, could I connect unused Port #2 in the diagram to the FEL valve and run the return to the transmission reservior?

NO!! You would have no pressure at 3pt or loader. Thats why you need the replacement block.

You are over thinking this. It is really simple - follow the directions as given.

There is no need to flush the old oil.

Dan

 

[Russell King]

You are currently using the transmission sump and fluid for the three point hitch. The FEL is currently a separate system. So the fluid may be different in those two systems.

But if you switch to the tractor pump then they will both use the same fluid. And as stated above there will not be any difficulties with some mixing of fluids. Don’t worry too much about it or drain and refill the transmission fluid after you switch the system over and have used it a few times. (There is not much volume of fluid in the FEL valve, hoses and cylinders compared to the transmission case volume.).

I would recommend the use of a Universal Tractor Transmission Fluid (UTTF) type fluid in the transmission. Don’t use pure hydraulic fluid in the transmission since there are gears being lubricated by that fluid.

I use Traveler brand UTTF from Tractor Supply but Walmart and other places have similar types of UTTF that are basically the same fluid and are basically the same as the original UDT from Kubota (which I think is now discontinued).

 

[Allegany Kubota]

NO!! You would have no pressure at 3pt or loader. Thats why you need the replacement block.

You are over thinking this. It is really simple - follow the directions as given.

There is no need to flush the old oil.

Dan

I'm an engineer and like to weigh options, alternatives, and solutions. My difficulties of this modification are routing the high pressure lines and building the replacement block. The alternative is rebuilding the sprocket chain coupler and repairing damaged keyways. The tractor has finished its immediate needs and I'll be parking it for a couple months for downtime.
Dan and Russel have been very helpful explaining what needs to be done. Thank you both.
Curtis on a small farm in Allegheny.

 

[TheOldHokie]

I'm an engineer and like to weigh options, alternatives, and solutions. My difficulties of this modification are routing the high pressure lines and building the replacement block. The alternative is rebuilding the sprocket chain coupler and repairing damaged keyways. The tractor has finished its immediate needs and I'll be parking it for a couple months for downtime.
Dan and Russel have been very helpful explaining what needs to be done. Thank you both.
Curtis on a small farm in Allegheny.

For the engineer. As far as the neutral circuit goes all valves have to be in series. Just that simple.

Dan