jturbo10
New Member
I have a 2006 John Deere 35D mini excavator that I use on my ranch. Recently I purchased a 28 inch thumb which welds to the bucket arm and has an extend and retract two way hydraulic cylinder. The 35d already had the auxiliary hydraulic plumbing with Faster couplers. Purchased an OEM John Deere male coupler and a Parker female coupler from Ebay. We tried to insert the male coupler into the female coupler I had purchased on Ebay but the aux female would not lock up to the John Deere male coupler. However each Ebay coupler did engage and lock with the JD 35 Aux Couplers when I added the hoses and cylinder connectors. The cylinder will close the thumb to the bucket but it will not retract. We get some fluid flow but no pressure to the non functional male hose side plus the flow will decrease when I push the aux pedal. The engine rpm lowers and we get the grunting signal but the cylinder will not retract. We switched from backhoe to excavator without any change. Both me and my part time employee are fairly knowledgeable mechanics but limited on how the aux system works. I know there is only one way flow for some aux attachments like a jack hammer but does that apply to a thumb????? Is there a switch to allow two way flow or a valve???? We are stumped on how to get the thumb to extend and retract. Any help would be greatly appreciated as I'm anxious to use my thumb on the ranch. Appreciate any suggestions. Thanks. Joe
! When posting please include machine serial number, thanks. Left side of the machine should be a rubber plug you remove and in there is a valve you can switch from one flow to two way flow.