My hoe boom just started drifting pretty fast on the last job.If you put down pressure on it,it will not move at all but from transport position to the ground it will drop completely in about 30 seconds.Did some diagnostic reading in my manual--there's a mention of a drift valve.Anybody know where this might be or any other logistics on my problem.Machine only has 2200 hrs.,oil,filters,and all other functions are perfect.
Hi tuney, I've worked on the 310 and 410 models, both in the C and D series, but I haven't worked on a G series, not familiar with the components Deere has on that model. Drift valve could be acting as a hyd holding valve to prevent drift of hoe boom as oil leaks around valve spool. It would have to be either located on the hoe cylinder or at the control valve. I'm trying to find the parts pages for your machine, and for some reason, the 410G isn't at the Deere website??? I can find every 410 series except for the G. :Banghead I'll keep looking this weekend, but if I can't find anything, I'll call my Deere dealer on monday and ask him what up with that?
Here's the hoe boom valve section for a 410J, may be some similarities. Item #28 at the bottom of the page is noted as "drift check". To look at that illustration, I don't know how that thing is operating as a check valve, might be worth looking into though. I take it this is a machine you own? If so, you really should contact your local dealer and obtain the hyd schematic for your machine. These machines don't use a simple hyd system, and a schematic would be a great help for you in troubleshooting problems.
I just wanted to mention that my machine has pilot controls--don't know if that makes a difference .
The only way the boom drift would be caused by pilot controls would be if the joystick lever valve was applying some pressure to the boom down side of boom control valve while joystick lever is in the null position. You mentioned the boom will drift down rather quickly, does it do the same with the engine not running?
Yes,it drifts down without the engine running.
That right there tells us it's not a pilot control problem. It could still be the piston seal in the cylinder, but I really don't think so in this case. It's hard for me to say for sure, but if your control valve section for the boom is like the one I posted for the 410J, I can somewhat see where item #28 is a load check for the boom. What I can't see is there is nothing in the drawing that would unseat the check when you go to boom down. I'm thinking there's a spool that's located in the port inline between item #28 and item #19 plug. That spool wouldn't be your problem, unless it's stuck, it's possible. Check your 410G parts pages and see if you have something like item 28 on your machine, I'd say your problem is there.
Fixed the problem.It was part #23,it's a screw that backed itself off,not holding pressure on the spring.Apparently,someone at Deere and Co. only put the smallest amount imaginable of loctite on the threads.The whole spool came out the top,not the bottom as my service dep't. at Deere told me.Too bad,I wouldn't have wasted about 3 gallons of oil.Anyway,this must have been loose for awhile because the boom always drifted a slight amount--more than an almost still new rig should.Now you can't see it move at all.I do see Deere didn't put all the different types of boom valves in my parts book--the one you posted here Atcoe is closer to mine on the J model than anything in my book,but it is slioghtly different.Thanks for your help.
Ha! Slayed the dog didn't ya! :woohoo Yep, if #23 came loose, the spool would shift off center. Thing is, if you had linkage controls you would have felt this. But since you have pilot controls, no way you would have known it. Well, seems the advice I gave didn't exactly fix your problem, but hey, got ya plundering around down in there 'till ya found it. Rock on bro.
hey guys i have a john deere 401d backhoe. I am having problems with the main boom control valve. I think the valve body is cracked internally. Does any one know where I can find a control valve for a 1985 John Deere 401d backhoe. Thanks.
Welcome to the forum randy144. :usa It would really be better if you get your three posts in somewhere and start your own thread about your question. But I have to ask, what makes you think the valve body is cracked?
I have changed the spool from another valve and the problem is still there. All the hoses and check valves have been checked. The only other thing left is the valve body.