Rotate circuit on Deere/Hitachi EX150-160

[excavator]

I need to pick some Deere/Hitachi brains, I'm plumbing a grapple rotate circuit on a Hitachi EX150-5. For what ever reason they decided to put the pilot pump inside the pump bell housing on these models so I can't use a tandem pilot pump. I'm currently plumbed into one of the test ports and it rotates OK but when you stroke any other function it spins way to fast. I looking for different ideas so when I hit the trigger it strokes the pumps, the solenoid valve has a relief built into it so I should be OK with full system pressure to it. Looking for different ideas, what others have done. TIA

 

[uffex]

Good day
Question does your machine have a option spool? if not we maybe can help with other suggestions, when you say the servo pump is in the bell housing could you post a photo please.
Kind regards
Uffex

 

[uffex]

Found this in the archives maybe it will help depending on what flow and pressure you are looking for.
KR
Uffex

 

[excavator]

The "option spool" is already being used for another function. As far as a picture, the pilot pump is inside the bell housing so not visible. I will see if I can download a parts breakdown. Thanks.

 

[uffex]

Good day excavator
Is the option spool required in combination with the additional rotation or could this be a doubled up for both another possibility is to use the swing if the swing is not used in combination of the new rotation. Our experience is that rotation circuits require low flow and pressure, have you any details on these ?
Kind regards
Uffex

 

[excavator]

This is on a rotating grapple so the thumb (aux) circuit is used to open and close. I'm working on the grapple rotate circuit which I can make work, I'm just curious if there are other ideas out there. Thanks again.

 

[TVA]

Do you need to use both functions simultaneously? If not you can install diverter valve to switch between them.

 

[uffex]

Good day
TVA point is where I was going but those we have been involved with require low flow & pressure in which case the additional vale may require these features.
Kind regards
Uffex