Backhoe Wobbly Backhoe

Kubota-monkey · Jun 23, 2000

Ok well here is my problem-
On my L35 when the throttle is up about halfway and I am using the backhoe, when I swing the backhoe from a side to center it shakes uncontrollably. I have to wait about 10 sec before the things settles back down. I have checked the nuts and bolts- everything seems tight. I even over-greased the thing to see if that would slow the shaking... Nothing worked! Right now I am at a loss as to what to do. Does anyone have any suggestions??-Thanks

Anonymous Poster · Jun 23, 2000

Is this a new backhoe? Has it always done this? With the hydraulic flow of the L35 if you move it to center without lightly "feathering" the stick...if you just jam the stick over and then let it go, the whole tractor will jerk around. Backhoe movements are supposed to be gentle.

Of course I can't know what yours is like to be sure if it's normal or not. I have a new one and also got to play with a 1400 hour L35 that lived it's hard life as a rental unit. I found the hoe on it remarkedly tight, was expecting it to be worn out. The tractor looked like it had been run through the grinder/w3tcompact/icons/mad.gif

It went for $13,000. Pretty good when some full-size "earthmovers" actually they are called motor scrapers went for $1500! 13,000lb excavators went for $6-10,000. One 60,000lb excavator went for $8500. Two D9L's went for $50K. Too much equipment not enough buyers this time I think. People were blown away in the audience. Wow, $1500 for the earthmover, I should have bought it and used it for a flower pot. These were all running items that went across the selling ramp. A couple of times my hands started shaking and I finally had to sit on them to keep from bidding on something I didn't need. Four 4x4 Case 580L Extendahoes went for $18K per, which is far under the "normal" 25K. These was a no reserve auction. Scary if you're the seller.

Von · Jun 23, 2000

Del,
I can't believe that you didn't get the earth mover for $1500.00! Talk about a conversation piece! My wife is glad I was not at that auction! You should have seen her face when I dragged home the 67' Zamboni for the back yard icerink!

Von

TomG · Jun 24, 2000

I don't think I know enough hydraulics to be much help, but as Dell mentioned, more information would be useful. From the question: I guess the problem has been there since you've had the hoe, it shakes when swinging to centre from either side, but not when swinging centre to side. More guesses are: The jerks are the same on both sides, and the other hoe operations are normal. I also guess, that the oil level was checked since the hoe was mounted; that the hoe runs from the tractor pump, and that other things like the loader operate normally. I'd also guess the hoe is operated with the loader bucket held on the ground.

Some types of hydraulic problems might be identified by operating the hoe with different engine RPM's, especially lower RPM. Also, by feathering the valve for different rates of speed. Another thing to check is whether the jerking is the same with the bucket full and empty. The swings also could be tried with greater and lesser stabilizer down pressure.

Such a specific and symmetrical problem does seems curious. On the surface, I'd suspect hydraulics, because there are a few parts that would be common to both right and left swing toward the centre. Ordinarily, I wouldn't expect wear or abuse to produce such a specific symmetrical problem. However, the pivot point and swing cylinder mounts and pins could be checked and swapped with other parts if possible. I wouldn't expect the pivot point to be put together with any threaded parts. However, if it is, then something could be too tight.

Swapping hydraulic parts also could help check out the problem. I guess the swing valve itself would be a good candidate. The swing cylinder is likely a lessor candidate, but it would be easy to swap if a similar cylinder is available.

Anonymous Poster · Jun 24, 2000

All operations are very jerky- as when I use the dipperstick the bucket shakes incredibly. The backhoe is used very little and is only a year old. I figure that this must be normal since there is no logical explanation-
Thanks for all the help

MChalkley · Jun 24, 2000

It's not normal, I'm sure of that, but I'm not sure what it is, either. I've rummaged through my hydraulics books, too, but they haven't been any help. Are the other cylinders acting the same way?

Mark

Anonymous Poster · Jun 24, 2000

I'd try to find a dealer with an L35, run it the same RPM and see how it acts. On mine, at anything above an idle, if you move the hoe without the loader bucket and legs down you can get thrown out of your seat if you aren't careful.