personally owned and used machine. later serial number range 559862. bought a year ago with 5000 hours. have put 500 hours on it problem free and has worked perfectly. now, out of nowhere i have observed the stick in function and bucket curl or in function slowed way down and now won’t come in almost at all. maybe if you hold joystick activated for 10 minutes it may creep just barely. when flip lever to bypass electronic mode it does the same. have gone thru instructions on computer box and no joy. i did notice a light of “heavy load sense” or something of sort on during one of the modes. little confusing how to interpret the lights and patterns. all other functions work perfectly, stick out, boom up and down, swing and propel i do have owners manual as well as tm1508 and tm1509. really don’t know where to start?? after reading theory of operation i noticed the two functions i have problems with are on different valve bodies???? have talked to a few local independent service techs and seem to get “trash in a valve” or stuck valve type of general thoughts. but two different function losses on different valve bodies???? no excavator expierence here but lots of mechanical expierence on dozers and other equipment. i am looking for advise on some checks to point me where to look.
Do you have the machine setup with the Deere control pattern ie: stick and bucket on the right side joystick ? If so , you may have an issue with the right side pilot controller.
yes, the bucket and stick are on right side joystick. when machine was first obtained, i only changed in versus out on stick direction. Has worked flawlessly since day one. I also noticed, bucket is slow to curl in and out, however, if you mix another control(like stick out) at same time, the bucket dump speed increases to normal speed. Only, stick in, and bucket both directions are suddenly at creep speed.
Does the bucket drift in either direction with all controls in neutral
i have not noticed it creeping just sitting un commanded, I do question from time to time when i first engage the safety arm to operate, a slight movement of the arm or bucket or some creep movement of some sort, but not sure. Its so slight, it almost makes me think its an illusion. I have also noticed that when start up first time of day, when you boom up, the stick may swing in freely a short to medium distance, like there is no oil on one side of the piston until you give it a command with joy stick. After you function it in or out (when it was working properly)it seems fine and no slack in the system of the stick. No other control demonstrated this abnormal "slack" as i call it, in a cylinder. I am not sure if there is any connection, but this problem showed up after trying to handle two big hardwood trees. After a couple attempts to grab up and relocate to a fire pile, I thought better of taking any chance of overworking machine since it seemed not so easy like most trees. I then resorted to cutting up in smaller sections to handle. Problem didn't just show up right away, its like over the rest of the day the two functions in question slowly disappeared. I would also offer the fact that since we obtained this machine and used it continuously, one by one the cylinders not only began to leak, but the piston packings failed. When we tore down, the packing and orings were coming apart in pieces, like dry rotted. The thumb cylinder, and crowd, then bucket cylinder months apart. We do know this machine has sat up unused for a period of time.
There is a stick in speed adjustment on the control block , maybe that is jammed up with debris restricting the oil flow.
I spoke with a knowledgeable person that is trying to help me, his first thoughts were port relief valve check. I failed to mention that a recent hose blown on the boom to stick location was just replaced in recent weeks. He offered that every service call they make, the first question they ask is "any blown hoses lately?" He says its very common to observe new hoses that were made up locally, often or never are rinsed and cleaned before installation. Chop saw cutting of hose material ends up leaving rubber and shards of steel debris in the uncleaned hose, that gets caught up in port relief valves and spool valves. He observes it may take a week or two sometimes to show the malfunction. He says now they rinse all NEW hoses before installation. Any advise at this point gives us something to eliminate. I wish I knew where to look. I did also read up in the manual about the bleed adjustment for "dead spot" on the stick while booming up, I have never made any adjustments, as its not been a problem...
I think it’s time to start pulling the stick and bucket spools from the control valves. They should move smooth as butter. I would also remove to check the stick in adjuster valve could be some debris restricting oil flow
may be moving in the right direction, not sure. Have swapped hoses on the manifold to reverse stick in and stick out. Now problem is on stick out. So that tells me no matter what function i connect to the "PULL BACK RIGHT SIDE JOYSTICK", that function will not operate. However, any non working function can be swapped to "FORWARD JOYSTICK" and that function will work. So it looks like the pilot control valve is the problem. Will pull and inspect or replace...
Apart from external oil leaks at the 4 plungers ,pilot controllers in general are pretty bullet proof. I suspect you have some dirt / debris in it. Take it apart, flush and clean everything really well and reassemble.