New EK1 series - weird hydraulics?

[valex1p]

new to the forum and looking for some advice and guidance...

apologies for the long scene setting!

I'm in the UK and recently purchased a new EK1-261 (a result of the purchase of Escorts by Kubota I believe and the machine is almost identical to the FarmTrac FT26).
The machine comes with an auxiliary rear single DA spool with QC. The dealer fitted a Kubota loader (actually manufactured by Tenias in Spain).
I have a tipping trailer with a 3 stage SA cylinder which has worked fine on my B1750 although it is a pain in the tush having to switch between 3 point lift and tipping pipe with the little valve under the seat.

Anyway I thought I would improve my life with the dedicated aux spool on the EK1. It doesn't even have a valve to switch between tipper and 3 point lift .

The dealer told me 'it will be fine' just connect the SA tipper to one of the QC's. It wasn't. The tipper raises but won't come down (as I suspected). I had planned for this and so swapped the single DA spool for a monobloc with 1 DA and 1 SA spool. Connect the tipper to the new SA spool- tipper goes up with spool in one position - and then goes up some more (though more slowly) with the spool in the other position. WTF???
After some head scratching and pipework chasing I deduced the following:-

1. The Tank connection from the spool goes directly to the 3 point hitch control block and must have some sort of restriction in flow such that a DA arrangement will go to tank OK as its under more pressure than my SA arrangement​

2. The restriction is causing small backfeed of pressure so that when my SA spool should be emptying to tank it is actually filling the ram a bit more.​

​

So I move things along by taking the tank connection from the spool off the 3 point lift hitch control and connecting with a T to the loader tank return. Now we have a slight improvement. Tipper goes up OK and comes down although pretty slowly. More weight in the tipper increases the down speed. Turn the engine off and the down speed is great and as expected.

So further deductions:-

3. The T in the tank return is shared with the loader and as the loader spool is open centre there is not enough pressure from the tipper going down compared to the returning pressure from the loader​

4. The 3 point hitch no longer lifts ). The tank out from the spool must act as the Pressure in for the 3 point hitch.​

​

So before I completely lose it does anybody recognise and agree with my deductions and any suggestions about what to do next?

 

[Russell King]

I am no expert on your tractor or hydraulic system but will say it sounds like you have a fairly good understanding but I will explain a few things just to clarify what should be going on.

Kubota tractors use an open center system which means the fluid flows from the pump into the valve (usually referred to as P port) and flows through the valve and out through the PB pot to the next valve‘s in port and eventually goes to the 3PH and dumps back to the sump. The valves can direct the flow and pressure into a cylinder that then moves. Usually the cylinder is double acting so fluid is on both sides of the piston. As one side extends the other side has to dump fluid back to the sump usually out a T port then into the main sump. There are a few instances where the T port is used for pressure out similar to the PB port, but that is limited.

You mention that the tractor has a loader and that is working fine.

You have a tipper (dump trailer) that has a single acting cylinder that you want to use and the tractor has a rear remote valve that is for a double acting valve. That has been replaced by a mono block valve that has a single acting valve but the tipper is still not working properly in the down (gravity) direction. It is too slow in the down direction.

So here is what I think is incorrectly plumbed: the new valve needs the tank line directly back to the sump of the tractor and a separate Power Beyond sleeve that also screws into a second T port in the valve that then goes to the 3 PH input. I think you are missing the PB sleeve since they are usually ordered separately from the valve. I am not sure that is the problem but please advise if you have the PB sleeve or not and how the rear remote is plumbed in more detail.

Hopefully that will help you resolve your issue but if not please provide more details about the plumbing and the valve you installed. For the valve provide the make and model if you can.

 

[TheOldHokie]

new to the forum and looking for some advice and guidance...

apologies for the long scene setting!

I'm in the UK and recently purchased a new EK1-261 (a result of the purchase of Escorts by Kubota I believe and the machine is almost identical to the FarmTrac FT26).
The machine comes with an auxiliary rear single DA spool with QC. The dealer fitted a Kubota loader (actually manufactured by Tenias in Spain).
I have a tipping trailer with a 3 stage SA cylinder which has worked fine on my B1750 although it is a pain in the tush having to switch between 3 point lift and tipping pipe with the little valve under the seat.

Anyway I thought I would improve my life with the dedicated aux spool on the EK1. It doesn't even have a valve to switch between tipper and 3 point lift .

The dealer told me 'it will be fine' just connect the SA tipper to one of the QC's. It wasn't. The tipper raises but won't come down (as I suspected). I had planned for this and so swapped the single DA spool for a monobloc with 1 DA and 1 SA spool. Connect the tipper to the new SA spool- tipper goes up with spool in one position - and then goes up some more (though more slowly) with the spool in the other position. WTF???
After some head scratching and pipework chasing I deduced the following:-

1. The Tank connection from the spool goes directly to the 3 point hitch control block and must have some sort of restriction in flow such that a DA arrangement will go to tank OK as its under more pressure than my SA arrangement​

2. The restriction is causing small backfeed of pressure so that when my SA spool should be emptying to tank it is actually filling the ram a bit more.​

​

So I move things along by taking the tank connection from the spool off the 3 point lift hitch control and connecting with a T to the loader tank return. Now we have a slight improvement. Tipper goes up OK and comes down although pretty slowly. More weight in the tipper increases the down speed. Turn the engine off and the down speed is great and as expected.

So further deductions:-

3. The T in the tank return is shared with the loader and as the loader spool is open centre there is not enough pressure from the tipper going down compared to the returning pressure from the loader​

4. The 3 point hitch no longer lifts ). The tank out from the spool must act as the Pressure in for the 3 point hitch.​

​

So before I completely lose it does anybody recognise and agree with my deductions and any suggestions about what to do next?

Zero familiarity with any of those makes or models but I think you are confusing a tank return with a power beyond circuit. Sounds like you have put a tee in the loader's power beyond that feeds the 3pt. As you discovered that will not work.

Post some pictures of both your loader valve and the two spool monoblock valve.

Dan

 

[TheOldHokie]

new to the forum and looking for some advice and guidance...

apologies for the long scene setting!

I'm in the UK and recently purchased a new EK1-261 (a result of the purchase of Escorts by Kubota I believe and the machine is almost identical to the FarmTrac FT26).
The machine comes with an auxiliary rear single DA spool with QC. The dealer fitted a Kubota loader (actually manufactured by Tenias in Spain).
I have a tipping trailer with a 3 stage SA cylinder which has worked fine on my B1750 although it is a pain in the tush having to switch between 3 point lift and tipping pipe with the little valve under the seat.

Anyway I thought I would improve my life with the dedicated aux spool on the EK1. It doesn't even have a valve to switch between tipper and 3 point lift .

The dealer told me 'it will be fine' just connect the SA tipper to one of the QC's. It wasn't. The tipper raises but won't come down (as I suspected). I had planned for this and so swapped the single DA spool for a monobloc with 1 DA and 1 SA spool. Connect the tipper to the new SA spool- tipper goes up with spool in one position - and then goes up some more (though more slowly) with the spool in the other position. WTF???
After some head scratching and pipework chasing I deduced the following:-

1. The Tank connection from the spool goes directly to the 3 point hitch control block and must have some sort of restriction in flow such that a DA arrangement will go to tank OK as its under more pressure than my SA arrangement​

2. The restriction is causing small backfeed of pressure so that when my SA spool should be emptying to tank it is actually filling the ram a bit more.​

​

So I move things along by taking the tank connection from the spool off the 3 point lift hitch control and connecting with a T to the loader tank return. Now we have a slight improvement. Tipper goes up OK and comes down although pretty slowly. More weight in the tipper increases the down speed. Turn the engine off and the down speed is great and as expected.

So further deductions:-

3. The T in the tank return is shared with the loader and as the loader spool is open centre there is not enough pressure from the tipper going down compared to the returning pressure from the loader​

4. The 3 point hitch no longer lifts ). The tank out from the spool must act as the Pressure in for the 3 point hitch.​

​

So before I completely lose it does anybody and agree with my deductions and any suggestions about what to do next?

As I said in my earlier response I know nothing about your specific machine but assuming Kubota is using their traditional CUT hydraulic system design this is the circuit you want.

RED is the high pressure oil flow
BLUE is the low pressure flow.

The loader valve should have two outlets. One is a tank return that goes straight to the sump and the second is a power beyond (often called High Pressure Carry Over (HPCO) in Europe) outlet that supplies pressurized oil to the 3pt. The HPCO outlet is what you use to feed your auxiliary valve.

Your monoblock valve needs to be plumbed with both tank and HPCO outlets just like the loader valve. HPCO is typically an option that you must specify/purchase with the valve Thats why I asked for a picture of your valves.

The main purpose of HPCO is isolating the tank and pump circuits to eliminate unwanted interactions like you are experiencing with your SA cylinder. There are times when you can cheat and use tank for HPCO but yours is not one of them. The original OEM DA valve could have been used for your SA application but not hooked up like the dealer told you

Dan

 

[valex1p]

Thanks Dan - makes sense when you draw it out like that. The OEM aux spool just had Tank out and no HPCO which confused matters for me.

Just need to collect the bits to plumb in the new aux spool HPCO/Power Beyond (which is actually stamped 'N' (Next??) and see if that resolves everything.

 

[TheOldHokie]

Thanks Dan - makes sense when you draw it out like that. The OEM aux spool just had Tank out and no HPCO which confused matters for me.

Just need to collect the bits to plumb in the new aux spool HPCO/Power Beyond (which is actually stamped 'N' (Next??) and see if that resolves everything.

As Russel said earlier to use the N (neutral) port for HPCO you typically need to install a conversion sleeve. Without the sleeve N is just the same as T and you are going to have the same issues

By chance, does your new valve look anything like this?

Dan

 

[valex1p]

Yup that is the one although mine has 1 DA and 1 SA. I have ordered a power beyond plug so hopefully all will be sorted once plumbed in.
For anyone else suffering the power beyond plug part no is MBV95C2GP for a valve in the MBV5 range.

 

[TheOldHokie]

Yup that is the one although mine has 1 DA and 1 SA. I have ordered a power beyond plug so hopefully all will be sorted once plumbed in.
For anyone else suffering the power beyond plug part no is MBV95C2GP for a valve in the MBV5 range. View attachment 129026

Figured as much. Badestnost is one of the biggest producers of those valves with several distributors here in the USA.

BADESHTNOST Plc. - Hydraulic products, valves, > HOME

Dan

 

[valex1p]

power beyond plug fitted and all issues now resolved!

Many thanks for the assistance.

 

[TheOldHokie]

power beyond plug fitted and all issues now resolved!

Many thanks for the assistance.

 

[joseph EK1-261]

new to the forum and looking for some advice and guidance...

apologies for the long scene setting!

I'm in the UK and recently purchased a new EK1-261 (a result of the purchase of Escorts by Kubota I believe and the machine is almost identical to the FarmTrac FT26).
The machine comes with an auxiliary rear single DA spool with QC. The dealer fitted a Kubota loader (actually manufactured by Tenias in Spain).
I have a tipping trailer with a 3 stage SA cylinder which has worked fine on my B1750 although it is a pain in the tush having to switch between 3 point lift and tipping pipe with the little valve under the seat.

Anyway I thought I would improve my life with the dedicated aux spool on the EK1. It doesn't even have a valve to switch between tipper and 3 point lift .

The dealer told me 'it will be fine' just connect the SA tipper to one of the QC's. It wasn't. The tipper raises but won't come down (as I suspected). I had planned for this and so swapped the single DA spool for a monobloc with 1 DA and 1 SA spool. Connect the tipper to the new SA spool- tipper goes up with spool in one position - and then goes up some more (though more slowly) with the spool in the other position. WTF???
After some head scratching and pipework chasing I deduced the following:-

1. The Tank connection from the spool goes directly to the 3 point hitch control block and must have some sort of restriction in flow such that a DA arrangement will go to tank OK as its under more pressure than my SA arrangement​

2. The restriction is causing small backfeed of pressure so that when my SA spool should be emptying to tank it is actually filling the ram a bit more.​

​

So I move things along by taking the tank connection from the spool off the 3 point lift hitch control and connecting with a T to the loader tank return. Now we have a slight improvement. Tipper goes up OK and comes down although pretty slowly. More weight in the tipper increases the down speed. Turn the engine off and the down speed is great and as expected.

So further deductions:-

3. The T in the tank return is shared with the loader and as the loader spool is open centre there is not enough pressure from the tipper going down compared to the returning pressure from the loader​

4. The 3 point hitch no longer lifts ). The tank out from the spool must act as the Pressure in for the 3 point hitch.​

​

So before I completely lose it does anybody recognise and agree with my deductions and any suggestions about what to do next?

New to the group. Had you tried this one.