We bought JLG 600S a few years back for work here at the farm and have an issue. New here so if this isn't the right thread, please let me know which one I need to go to. My issue is with the basket swivel(left to right) Was using it on an extremely cold day and the bucket will now move to the side on it's on when on a lean. It's like a check valve isn't closing. Switch/control will move it find, it just bleeds off. You can move the basket with your hand. Any experts know what I need to look at? Is it in the hyrdraulic motor itself? Forgive my rookie question.
Try bleeding the rotator real quick. Make sure its stowed in travel mode. All boom sections fully retracted, boom fully lowered and creep mode off for functions..there are two screws on the side of the rotator. Loosen them up and see if the basket moves. How easy does the basket move by hand ? Freely or does it have some resistance? Some times the bolts that hold the basket bracket to the rotator sheer off and will allow the rotator to spin with out taking the basket. Probably a good idea to check those for tightness if you have not done so. The plastic cover is held on with two bolts. If bleeding it does not help let us know and we can go from there.
Just as a side thought was it working good before that particular day ? The rotator is not a motor its a helical swivel. The manifold thats mounted to the rotater also has two holding valves one per side.It gets fluid from the function manifold under the hood. In all my years i have never seen one fail internally but have resealed alot of them. Also when you activate the toggle to swing the basket do you see the lines that feed the rotator jump and get stiff like they are getting pressure ? They should flex when you stroke the function. If they are flexing try to bleed it first. Sorry for jumping around it just popped into my head after re reading my post.
Thanks for the reply. It was working fine prior to this and had no "slip" what so ever. you can move the basket VERY easy with one hand. Had some leaky hoses and replaced those over the past few years but none within 6 months so not an air issue. May be a little while till I get back to it as I have other things going on but I will reply with what I find. I appreciate the info to where to start looking. This unit was a low hour unit bought from a dealer in the last bigger recesession. We do use it quite a bit for a private owner and really like it.
If you can push the basket by hand with ease check your holding valves. They should basically hydro lock the system to prevent movement. You can pull them out and make sure nothing is stuck inside one and that they are functioning correctly. I would look there first and let us know.
Where is the "holding valve" located?
On the rotator you will see a manifold mounted to the front where the hydraulic hoses connect. The holding valves top and bottom of that manifold block.
Thank you sir.
Ive replaced alot of broken bolts where the rotator attaches to the bascket. Many with all the bolts broken. just a shot in the dark but did you check the bolts on top of the rotator
I have a lot of things to check now Thanks to you guys. Working 7 days and 10hrs so my time is limited. Trying to get ready for another concrete pour so it may be a little while till I get back to it. I now have a plan of attack or know what to check so I WILL report back with what I find. So nice you all are willing to help a newbie out.
Had a few minutes and checked a few things. I took one of the eight bolts out of the top and it was not sheared. Didn't see the need to pull any more. I got an Allen wrench loosened one of 2 plugs on the side of the drum and I guess that is the bleeder? What is the process to bleed? New detail is the basket only bleeds off on one side. Meaning when it is straight you can spin to the right(looking at controls) but when you push it back it will NOT go passed being straight. I looked on the bottom but don't see anything else other than the main center bolt. I haven't taken the holding valves off yet.
Flip the two hose on the rotator. Its a quick check. If the basket then goes the other direction with hoses flipped the problem is most likely one of the coils is not working or you can flip the coils as well. What is easier for you. The bleed screws actually bleed the rotator. Since its a helical gear and not a large volume of fluid actually passes through the helical air gets trapped in the screw and cant work its way out as easy as say it could in the cylinder. But since your moving in one direction i would start to focus in on the coils or toggle switch. You can always check with a meter but since im usually always by myself in the field i find the hose swap method works best for me and is the quickest way.
The basket will move when using the toggle switch in both directions as designed. It just bleeds off on the one side and you have to keep moving it back when you are in an incline. Guess I wasn't clear on that.
Ahhhh gotcha. I was working under the impression it did not rotate. If its bleeding off then one of your holding valves is the most likely culprit followed by the shuttle valve for basket rotate function.
Had some time and pulled both holding valves off. They look to be the same so I figured I'd compare them. I cleaned both and pulled the snap ring, disc, spring and bottom "piston" with the teflon split ring and Oring. Nothing damaged or nicks in the orings anywhere. The one oring behind the telfon did look a little smaller than the other side but didn't have one the correct size here to replace it quick. Does the valve come apart more than that? There looks to be a stud where the "piston" hits but didn't want to come out. All the port holes were open and no dirt anywhere. I put the back in and it still does the same thing.