What would cause jerky movements only on boom and no where else?
Read this thread.
Bowden, did you figure your's out? and do you mean that air is the problem for Reilly? The boom cylinder is the largest so it takes the most flow. That could be why the jerkiness only shows on the boom. Also, on the previous thread, do these machines have safety valves so the machine won't drop if the engine is off and the stabilizers are let up? Either that or just the small hoses could explain the stabilizers putting more load on the engine. It's not too likely that you bent both of your rods?
I added some fluid which helped but the problem is still there. I suspect I have some contamination on my fluid. I plan to change it but I wanted to wait until I get all the seals replaced because this will lose lots of fluid anyway. I do not think the stabilizer rods are bent but I did oil the pivot points good. Mine jerks worse after the fluid gets really warmed up.
Hey, your stabilizer cyls. have lock valves on them thus it takes more power to operate them (they wont work without the engine running) safety feature,, as far as the boom , I think as another has posted, maybe valve problem, we have a 580C and the boom valve section cracked inside, but make sure all linkages are oiled properly to , good luck