here is a basic ms paint shematic hope this will help...
this valve body is mounted in serial before the bh65 valve body
a power beyond needs to be installed.. to avoid pressure buildup in the thumb valve body by operating the backhoe
an aditionnal drain line for the thumb needs to be...
i had the same problem with mine.. i used the same valve body as you...
i put a power beyond into it... placed before the backhoe valve body... i also plumbed a 3rd return line for the thumb cylinder
and ajusted the line releif a little lower than the bucket this way if i close the bucket the...
this is my home made hydraulic full rotation thumb for a bh65 with a quick coupler that i made... ( a video of the coupler is available on youtube )
actually i havent finished totaly my project...
video of the coupler