I am working on a 310 SG John Deere. I had to change three of the back hoe valve sections, the boom section, the croud section and the extend-a-hoe section. When the machine is started the boom picks the machine up and you cant move the control lever to a natural poshion and have no loader controls at all. The locai Deere dealer is also scratcihing their heads also.......................any ideas ?:Banghead
Does it have pilot controls. Did you dissasemble the valves and mix the spools up
No pilot controls and I replaced compleat valve sections. I only took apart the old ones to find that were worn out.
Are the O rings seated between sections
I had no external leaks what so ever
Can you move the spool when the engine is turned off?? If not have you over tightened the through bolts?
I figured it out back a few days ago, I have a helper in the shop. I had told him that he needed to mark every hose and connection so that everything would go back in the same place. Un-known to me, he only marked the hoses out of the valve body to the boom and not the hoses going in to the valve body on the back. After some time in the book looking at the flow charts, I found that the pressure and return lines were reviersed, the flow was backward. Thanks for all of the help.