I have a Genie S60 2001 year model that shakes/shudders when extending the boom. Now here is some details: all wear pads have been replaced or shimmed to tolerance, it does not shudder when boom is raised above horizontal, it does not shudder when retracting at any time no matter the boom position. So is it a hydraulic problem? Is the boom bent/twisted? We use this machine daily and the problem just kind of started one day. I cannot seem to nail it down. Machine is serviced regularaly with fresh oil and filters both engine and hydraulic.
did you replace any hydraulic lines recently? could be air in the cylinder?
Raise the boom to full height, Extend option 1: still shudders = issue is in cylinder option 2: boom extends normally = issue is caused by stiction.
It takes a while to work into the system, but a hydraulic oil additive such as "Lucas Hydraulic Oil Booster" solves or greatly improves the boom chatter problem in a lot of cases.
I don't know if it would help but we spray graphite on the boom which seems to help.
Check your extend/retract cables. Make sure they're tight.
If the shop you took it to for the wear pads and shims did them correctly make sure your cables are adjusted properly if it all checks out grease the boom sections where the pads ride. A lot of the time its that
Did you check to make sure the wear pads on both front and rear ends of the boom are adequate? For my fleet, usually when I encounter the same problem it is usually attributed to the lack of lubrication between contact points of the boom and wearpad. Get someone to apply sufficient grease on all surfaces touching the wear-pad and repeat the process of retracting and extending the boom until the problem fades away.
Well, my S60 is doing the exact same thing. Pads are good, and greased. Good fluid levels. Does not shutter above horizontal. During shutter the PSI bounces from 750-1250. I'm trying to see if my base idle PSI is too low and maybe a counter balance valve is coming into play. But I would think the boom lift position shouldn't matter then. Before I start tearing into this or buying pricy parts, I figured I would see if anyone has any ideas. Also checked relief pressures and proportional valve.
have you tried lubing the inner boom pads that you cant see? try that first before you get into hydrualics.