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Bobcat 335 300 hours Jerky Hydraulics

Yellowdog

Well-Known Member
Joined
Oct 22, 2004
Messages
208
Is it just me or does a 2009 Bobcat 335 have jerky hydraulics? My machine is ultra low hours for the year.. we only use it for loading a trailer and planting trees and occasionally for moving/digging boulders. The turntable feels a little sloppy too. When I stop the slew, it seems to go back and forth a little. Is that normal? The rest of the machine, boom, stick, are all tight. Lots of power, too, for digging but I just don't have much control even with low rpms.

I feel like I can't do anything right lately with the hydraulics. I can make my hand controls in my s750 and Toolcat do whatever I want but not so in the 335. Is there an adjustment or is this just par for the course? Is there a good rpm range that someone has discovered where I can smooth this thing out some?

Note: I've had this machine since new but don't get to use it much and going from the s750 to the excavator makes me feel like I'm a noob and I'm frustrated.

By the way. Merry Christmas everyone!!
 

bigsmoke

Active Member
Joined
Aug 21, 2014
Messages
27
Location
Canada
Occupation
Heavy equipment mechanic
Jumpy hydraulics would make me wonder what your pilot pressure is; if it's too high or low, you won't be able to feather anything to save your life.

As for the rocking in the house, I'm fairly certain the 300 and 400 series excavators did not have slew brakes, but the newer M series do. The slop you feel is just the clearance between the slew gear teeth and in the motor.
 

KSSS

Senior Member
Joined
Feb 27, 2005
Messages
4,318
Location
Idaho
Occupation
excavation
I think BC has always had those "highly responsive hydraulics" as far back as I can remember. I spoke to some BC engineers about it one time and was told that is the way the BC customers want them to run. Highly responsive and fast is what they want and most BC excavators I have run behave like that. Now whether yours is overly sensitive I don't know. Have you run any other BC excavators to compare how others react?
 

Yellowdog

Well-Known Member
Joined
Oct 22, 2004
Messages
208
I've run a 331 a couple of times. I don't remember it being that jerky. Maybe I'm just out of practice but they are responsive. When I am digging, I can shake my bucket quickly to dislodge dirt and the thumb is ultra responsive. Slew is fast, too. Wish it had a slew brake as I hate the feeling that it's gonna break with the little studder at the end of my slewing. All in all, I like my machine and plan on keeping it as it would be hard to replace in the hp to weight ratio I have. I can dig almost 12 feet and lift more than I should be lifting.

As far as pilot pressure, I guess I'd need the dealer to check that. I know that my machine has 26 gpm for hydraulic functions and that seems like a lot for a small machine. Maybe I need to drop the throttle even more?

I'm 100% self-taught on everything. My speciality is running a skid steer and grapple and mulcher and I can do amazing things with those but I wish I could find someone around here that is gentle but skilled in operating an excavator so I could pick up some pointers. I drive by construction sites and it's funny to watch the guys jerking around and bouncing the machines. Not too far back I watched a guy digging with a backhoe without his stablizers down. It was crazy and he was throwing himself all over the place... on a commercial project nonetheless.
 
Last edited:

melli

Senior Member
Joined
Dec 15, 2012
Messages
260
Location
BC
I am probably stating the obvious, but I always put my blade down to stabilize while digging (a little positive downward pressure on blade). Things stop bouncing and jerking around a whole lot. My back thanks me.
 
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