I bought a 2020 L3901 with bh77 hoe. From day one, when I'm on a hard dig the dipper has a chatter or quite short jumping pattern. It starts when dipper is just about at its hardest pull pressure, then when I pull back the boom to help the dipper along it chatters even more till the ground finally starts to cut easier and chatter goes away. I can make it do this every time. The boom cylinder seems to carry the noise the most and you can feel it through the platform and controls. It's back at the dealer for second time. I had a previous B3300 with same hoe and never made noise. They checked for air in fluid and said was none. Nobody seems to have a clue. Question : Can a relief valve be sporadic and not smooth?
BH77 issue with chatter
- Thread starter Manhut
- Start date
nbryan
Well-known member
Equipment
B2650 BH77 LA534 54" ssqa Forks B2782B BB1560 Woods M5-4 MaxxHaul 50039
Doesn't sound like anything that my BH77 has ever done. If the tractor has a loader, is there any similar noise/vibration using that? In case it's hydraulic pump related?
One thing I found with my new BH77 (in 2017) was that the control levers struck the metal framing and cover plate in 4 places when trying to operate them to their full extent. I had to bend forward the handlebar a bit at the top as the right lever hit it before fully opening. And I simply removed the cover plate to deal with the other 3 contact spots on it, leaving the rubber boots on the levers. No more travel interference, and full speed/power every direction now, which actually was a noticeable improvement especially with swinging the boom left.
I also re-tightened the link rod bolts where they attach to the spool, as several had come loose. Now after a few seasons of use, even with lock-tight on them, they're loose again and I'll have to remember to get in there before I forget and fix that again. That alone makes a huge difference in control!
Could it be that play in the lever links causing the chattering on your backhoe?
The only other thing that comes to mind is as it's a new machine that there's something stuck in the valve assembly somewhere, in the spool, or relief valve, from manufacture, that escaped QC. Or a defective component or hose.
No nothing happens with front loader. I'm still thinking it's more with the spool.
leveraddict
Well-known member
Equipment
2017 BX23S 60" LP BoxBlade 54" mower 60" BackBlade EA 12" 1 bottom plow & Forks
Are any of the grease zerks on the backhoe painted over? This has been a problem lately with Kubota. The paint on the zerks wont let grease enter and the pins are dry and some break!
If I were at the end of my rope, I would probably swap two functions and see if the problem moved. If so then I would suspect the control valve.
Swapping functions would require swapping pairs of hoses connecting to the control valves. Not sure if you are up to this. OR if the hoses are long enough to make the swap possible.
The goal would be to isolate whether the issue is with the control valve or the boom mechanics.
Just an idea...
almost sounds like you're chattering across hard packed surfaces, which is normal--that's just asking too much of the little back hoe and will break stuff quickly.
There could also be possibility of a safety valve that is sticking then releasing-causing chatter. Remote possibility at that.
does it chatter with no load on it?
There could also be possibility of a safety valve that is sticking then releasing-causing chatter. Remote possibility at that.
does it chatter with no load on it?
My first impression was it was happening on no load, but on reread, that does not seem to be the case.
Puzzling. I’ve used my backhoe a lot and never experienced chatter like that.
It does it on regular dirt. Remember how it jumps and chatters when your skipping across a hard rock. well that's kind out the vibration you get just no so dramatic.
Good idea, right now it's at the dealer. I don't know how good their call in tech help is but I guess I'll find out. It's under warranty now so don't want to touch it.
I have the same problem with chatter on my bh77. I get chatter when I swing the boom either way, right or left. I have 137 hrs on it and this just started. And you can feel the chatter. The pivet joints have plenty of grease.
Manhut, could you let me know what the dealer found? Thanks
Manhut, could you let me know what the dealer found? Thanks
I have a fairly new B2601 with the BH77 back hoe, and once in a while I was getting the chatter. I found that each time I have to install the back hoe on the machine again, the first thing I do is do a stretch. I extend the booms out as full as they go. Run side to side and curl the bucket. I also run the outriggers down and up one time. I do this for two resons. One is to get any trapped air to move, and second making the movements help the grease to coat the pins and joints before I use it. Since doing this, I have not had any chatter at all.
Not sure if that helps your situation at all, but when I mentioned this to my dealer about that chatter, he told me to move everything like I now do to help any trapped air that may have gotten in the lines from disconnect and reconnect.
Hope you get it figured out soon. Good luck.
Not sure if that helps your situation at all, but when I mentioned this to my dealer about that chatter, he told me to move everything like I now do to help any trapped air that may have gotten in the lines from disconnect and reconnect.
Hope you get it figured out soon. Good luck.
Last edited:
dirtydeed
Well-known member
Lifetime Member
Equipment
B2650 BH77, U27-4R2, BX23TLBM, box blade, rear blade, flail mower, Stump Grinder
Manhut, what position is your three point hitch control lever in when you have the hoe mounted/in use? Is it possible that your 3PH is trying to lift/bottom out thereby siphoning off fluid/pressure from your hoe?