Kubota mixup ?? on Pump Line hose and Power Beyond Line hose installation to loader

[Tx Jim]

Out of the 4 LA1002 FEL variations only 2 are for model M6800 tractors. Both loader valves I looked at had relief valves listed on the valve component pages. Photo of RV is later FEL serial number. What's the serial number of loader in question?

 

[J_J]

Jim,

I agree with you in what is displayed.

I never saw a relief valve in the pictures.

However jasong123 observed that the loader valve does not have a relief valve, but instead, a plug or shut off valve.

I looked at all 4 loaders.

At least one of the loader for the M6800 has a shut off valve. Several of the loaders had a relief valve on the loader valve.

Now, that brings up the question, what is the routing for the pump flow.

If there is only one relief on the tractor, and the one I saw was at the rear, then that would mean that the relief is before the 3pt and all other circuits including the loader.

I can not recall when an open center loader valve did not have a relief valve.

You really only need one relief valve before the first valve.

If wen would tell us the loader number we could probably determine how things work.

He says his tractor does not have a hyd blk.

However in some of the PDF's I see a hyd block and some of the other loaders has a coupling that connect a line to the back of the tractor.

 

[Tx Jim]

J_J
I was replying about a LA1002 loader not a TL421 such as jasong123 has. IMHO Kubota parts schematics are the most difficult schematics I've ever tried to look at. I did not see a shut off valve on the FEL(LA1002) control valve for a M6800 but I'll look again. UPDATE: I still can't locate a shutoff valve for a LA1002 FEL valve. Were you looking at Kubota parts or somewhere else? Here's a schematic for the hyd block for attaching LA1002 on a M6800

 

[J_J]

Look up loader LA 1002 -68R/6R1 control valve

Definitely a shut off valve.

Item 130

 

[Tx Jim]

OK but 120 that 130 is included into states it's a load check valve on the page I viewed. To make any good judgments one needs the FEL serial number.

 

[W5FL]

Here is the p/n and s/n of the Loader on my M6800 tractor. LA1002-68R S/N 10082

 

[J_J]

I looked at the PDF for your loader, and it does not have a relief valve, but does have a shut off valve.
Item 130 in the PDF for the LA 1002 68R


Apparently the only relief on your tractor is back on the 3pt assembly.

Somehow the relief valve is just after the pump and before any valve sees the flow.

I have not seen this setup before., and the other loaders for the M6800 are different .

It don't make sense, but it is what it is.

It took 36 post to find out the exact model number, and that poses a problem when trying to do long distance troubleshooting.

Here is a description for a shut off plug.

A SHUT-OFF PLUG P/N 52610 IS PLACED IN THE AUXILIARY
PORT TO DIRECT THE THRU NEUTRAL PASSAGE TO HIGH
PRESSURE POWER BEYOND. POWER BEYOND IS ACTIVE
WHEN ALL THE SPOOLS IN THE VALVE ASSEMBLY ARE IN
THE NEUTRAL POSITION.*

A closed center valve would use a shut off valve, and you also plug the PB to make that valve a closed center valve.

I have no idea why they choose to use only one relief, whereas some tractor have 3 to 4 relief.

 

[Tx Jim]

J_J
According to Messicks 52610 isn't the complete part number. Most Kubota part numbers have 10 or more digits. Can you post the PDF that you're viewing? What type closed center system have you seen with a shut off valve and a power beyond plug as I can't think of any JD's I been around with those items??
Thanks,Jim

 

[W5FL]

I looked at the PDF for your loader, and it does not have a relief valve, but does have a shut off valve.
Item 130 in the PDF for the LA 1002 68R


Apparently the only relief on your tractor is back on the 3pt assembly.

Somehow the relief valve is just after the pump and before any valve sees the flow.

I have not seen this setup before., and the other loaders for the M6800 are different .

It don't make sense, but it is what it is.

It took 36 post to find out the exact model number, and that poses a problem when trying to do long distance troubleshooting.

Here is a description for a shut off plug.

A SHUT-OFF PLUG P/N 52610 IS PLACED IN THE AUXILIARY
PORT TO DIRECT THE THRU NEUTRAL PASSAGE TO HIGH
PRESSURE POWER BEYOND. POWER BEYOND IS ACTIVE
WHEN ALL THE SPOOLS IN THE VALVE ASSEMBLY ARE IN
THE NEUTRAL POSITION.*

A closed center valve would use a shut off valve, and you also plug the PB to make that valve a closed center valve.

I have no idea why they choose to use only one relief, whereas some tractor have 3 to 4 relief.

Sorry, JJ. I didn't remember you ever asking for the loader number and s/n. I did look it up on Messicks and it is confusing, but if you know to go to the B001606 version, then they call the entire assembly that shows in my first picture "a hydraulic block" (the one with the wrench on it).

The picture on Messicks e-mail does show all three hoses and where they go, but does not identify them as power/beyond, pressure, or return. I believe I have all three hoses connected correctly now. I do know a little about hydraulics, having designed and installed a rotary hydraulic actuator that was used on test aircraft to flutter surfaces to determine the aircraft stability.

It was more difficult than it should have been to simply determine if the hoses were connected properly even though the Kubota documentation was obviously incorrect.

I am still unsure of what should have happened if the pump hose to the loader and the power beyond hose were reversed as shown in the Kubota installation manual. For me, it just didn't work that way.

Thanks again to all who contributed to this thread.

 

[Tx Jim]

I looked at the PDF for your loader, and it does not have a relief valve, but does have a shut off valve.
Item 130 in the PDF for the LA 1002 68R


I have no idea why they choose to use only one relief, whereas some tractor have 3 to 4 relief.

According to FEL serial number(LA1002-68R S/N 10082) outlined in red the valve in photo is the correct valve with no shut off valve listed.