JCB 8026 Hydraulic Schematic

[HeliPilot]

Hi

Could anyone possibly help reading the attached hydraulic schematic?
The 8026 currently has proportional control with a roller button on the right joystick which controls the current auxiliary.

I’m looking to install a secondary auxiliary which will take its oil from the boom swing via the current changeover valve, the changeover valve is operated via push button on the left joystick. (So push left button and boom swing disables and new secondary aux enabled)

The machine currently utilises the changeover valve to swap the current aux function from the right button to the foot pedal

Hope this all makes sense

 

[jd6820]

Hi

Could anyone possibly help reading the attached hydraulic schematic?
The 8026 currently has proportional control with a roller button on the right joystick which controls the current auxiliary.

I’m looking to install a secondary auxiliary which will take its oil from the boom swing via the current changeover valve, the changeover valve is operated via push button on the left joystick. (So push left button and boom swing disables and new secondary aux enabled)

The machine currently utilises the changeover valve to swap the current aux function from the right button to the foot pedal

Hope this all makes sense

Looks like after reading the diagram that the changeover valve simply swaps which function is driven by the proportional roller on the joystick? I'm assuming you are wanting to use the pedal and roller to make up two auxillary services, one service driven by each?

 

[jd6820]

The only way I could see you can plumb that second Auxillary in, given the fact you don't have an auxillary slice spare in your valve block is to divert the boom swing to make your second auxillary service using a 6 x 2 diverter and use a relay to switch it when you press the button on the joystick or flick a switch on the dash.

You wouldn't gain anything taking it off the changeover valve itself as all that is doing is diverting pilot oil pressure to the corresponding valve, either auxillary or boom swing. Unless you pilot control an additional service added to the machine but that's just getting more complicated. Unecessarily in my opinion...

 

[HeliPilot]

Looks like after reading the diagram that the changeover valve simply swaps which function is driven by the proportional roller on the joystick? I'm assuming you are wanting to use the pedal and roller to make up two auxillary services, one service driven by each?

Yes kind of. But im thinking of changing the foot pedal to a solinoid valve which will opperate via a roller button on the left joystick. And yes one service driven by each.

 

[jd6820]

Yes kind of. But im thinking of changing the foot pedal to a solinoid valve which will opperate via a roller button on the left joystick. And yes one service driven by each.

Have you got the joystick/ roller for the left side and the associated valve and hardware to drive said valve, then you've still to switch oil flow at the main control valve to change oil flow from boom swing to second aux as there isn't a spare valve slice according to that schematic? Just done an E27/DZ27 machine and simply diverted the boom swing. You could achieve the same only using the pedal for boom swing/one aux and the roller for the other auxillary...

 

[HeliPilot]

Have you got the joystick/ roller for the left side and the associated valve and hardware to drive said valve, then you've still to switch oil flow at the main control valve to change oil flow from boom swing to second aux as there isn't a spare valve slice according to that schematic? Just done an E27/DZ27 machine and simply diverted the boom swing. You could achieve the same only using the pedal for boom swing/one aux and the roller for the other auxillary...

I do have a left joystick roller fitted and wired with a second ecu, which should control a solinoid valve replacing the (foot pedal)

 

[HeliPilot]

Have you got the joystick/ roller for the left side and the associated valve and hardware to drive said valve, then you've still to switch oil flow at the main control valve to change oil flow from boom swing to second aux as there isn't a spare valve slice according to that schematic? Just done an E27/DZ27 machine and simply diverted the boom swing. You could achieve the same only using the pedal for boom swing/one aux and the roller for the other auxillary...

The electrical schematic assumes a new second service slice is fitted to the main valve block...!

 

[CPS]

So at the moment your proportional roller just works your Aux service?
What you are looking to do is fit a 6 port diverter valve to the offset circuit and switch 2 services right?
If you did this as the machine is then your second service would be on the foot pedal when switched.
So you want to remove the foot pedal and fit a feeder valve to run the offset and second aux.
Hope im reading it right and making sense..... if so then yes, remove the foot petal, fit a feeder valve (i can supply you one if needed) and fit a diverter to the offset .... job done

 

[HeliPilot]

So at the moment your proportional roller just works your Aux service?
What you are looking to do is fit a 6 port diverter valve to the offset circuit and switch 2 services right?
If you did this as the machine is then your second service would be on the foot pedal when switched.
So you want to remove the foot pedal and fit a feeder valve to run the offset and second aux.
Hope im reading it right and making sense..... if so then yes, remove the foot petal, fit a feeder valve (i can supply you one if needed) and fit a diverter to the offset .... job done

Yes to the first question
I am looking to divert the offset but by utilising the current changeover valve.
I have a solinoid valve to replace foot pedal valve and this will be controlled via roller button on left joystick

Going back to the hydraulic schematic my question is how to make the changeover valve switch from offset to secondary aux service?
As it currently is the function of the changeover valve is not necessary, as all it does is switch the current aux from roller button right joystick to the foot pedal. (pretty pointless function)

 

[CPS]

Im finding it tough to read the schematic on my phone.
So, do you have 2 foot pedals or 1? Or does one pedal do both the offset and Aux when switched?

 

[HeliPilot]

Im finding it tough to read the schematic on my phone.
So, do you have 2 foot pedals or 1? Or does one pedal do both the offset and Aux when switched?

Only one foot pedal which swings the boom when the roller button right joystick runs the aux.
With the left joystick button pressed boom swing stops and roller button r/j stops, but now foot pedal runs the aux.
The changeover valve basically gives you the option to run the aux from roller button or the foot pedal, but while runnung the aux from the foot pedal there is no boom swing.

 

[CPS]

Ok, il have another look on the laptop tomorrow. But im thinking your best forgetting about the change over valve, replace the foot valve with the pilot solenoid valve and divert the offset.

Use the joystick buttons to operate your diverter valve and this way your current aux switch over is done away with

 

[HeliPilot]

Ok, il have another look on the laptop tomorrow. But im thinking your best forgetting about the change over valve, replace the foot valve with the pilot solenoid valve and divert the offset.

Use the joystick buttons to operate your diverter valve and this way your current aux switch over is done away with

Ok many thanks for your help.
I thought the changeover valve was the same a diverter valve?
There is another button on the back of the joystick that is'nt connected, so this could be used for the diverter.

 

[V8Druid]

Only one foot pedal which swings the boom when the roller button right joystick runs the aux.
With the left joystick button pressed boom swing stops and roller button r/j stops, but now foot pedal runs the aux.
The changeover valve basically gives you the option to run the aux from roller button or the foot pedal, but while runnung the aux from the foot pedal there is no boom swing.

weird set up

 

[jd6820]

The electrical schematic assumes a new second service slice is fitted to the main valve block...!

Ah you’d be able to swap the foot valve for the pilot block that is driven by the ECU which it seems you have all the equipment for. But you would need to pipe up a diverter into the boom offset output so you can create an auxiliary service as according to the supplied diagram there isn’t a spare valve for you to drive with hardware you have. Sounds like the hardware you have will simply replace the pedal and operate either the boom swing or aux. I’d simply unplug the changeover so it defaults to boom on foot pedal mode. Since you are changing the foot pedal valve with left roller it will be your new boom offset control then put a 6x2 diverter into the boom swing line that when you press button on left joystick it diverts from boom offset to aux 2. May need a latching relay depending on how the button is currently set up.

See diagram as I can only see one service not the two you’d need to get away without diverting boom offset.

 

[HeliPilot]

Ah you’d be able to swap the foot valve for the pilot block that is driven by the ECU which it seems you have all the equipment for. But you would need to pipe up a diverter into the boom offset output so you can create an auxiliary service as according to the supplied diagram there isn’t a spare valve for you to drive with hardware you have. Sounds like the hardware you have will simply replace the pedal and operate either the boom swing or aux. I’d simply unplug the changeover so it defaults to boom on foot pedal mode. Since you are changing the foot pedal valve with left roller it will be your new boom offset control then put a 6x2 diverter into the boom swing line that when you press button on left joystick it diverts from boom offset to aux 2. May need a latching relay depending on how the button is currently set up.

See diagram as I can only see one service not the two you’d need to get away without diverting boom offset.

View attachment 53241

Apologies for not replying sooner only just seen this.

Many thanks for the response this definitely seems my best option.

 

[HeliPilot]

This is how it looks with a second service line, notice a slice has been added and the changeover has been removed.
I've avoided this option as it seems a great deal of work and fairly complex
JD6820 did mention this option earlier.

 

[jd6820]

This is how it looks with a second service line, notice a slice has been added and the changeover has been removed.
I've avoided this option as it seems a great deal of work and fairly complex
JD6820 did mention this option earlier.

Changeover valve is still there, take a careful look at the diagram but you are correct in saying that diagram has an extra slice. The ideal way to do it but would require messing with the main valve bank.

 

[HeliPilot]

Changeover valve is still there, take a careful look at the diagram but you are correct in saying that diagram has an extra slice. The ideal way to do it but would require messing with the main valve bank.

Are you still looking on your phone? Chengeover has definately gone it was directly above the double acting option (Ball valve)

 

[jd6820]

Are you still looking on your phone? Chengeover has definately gone it was directly above the double acting option (Ball valve)


View attachment 53334

I do see, that’s the iso/sae changeover. I was always referring to the electric changeover valve that switches between joystick and pedal.