Backhoe Cylinder Squealing Bad

[dltucker001]

I've got a new Kubota L3901 and a BH77. I'm at 121 hours on it and most of that has been on the backhoe. Just in the last 10 or 15 hours the dipperstick cylinder (I believe) has started squealing when I extend or contract the arm. It sounds like metal on metal but all the zerks are loaded and the hydraulic fluid level is good. What else can it be? I don't want to cause any damage so it's just sitting idle now. And it's killing me. Help!!

 

[blacklion66]

Sounds like a relief valve! not a cylinder. look for something bent or broken, starting with the cylinder. If you don't find anything, a hydraulic pressure gauge might help in trouble shooting

 

[rScotty]

I've got a new Kubota L3901 and a BH77. I'm at 121 hours on it and most of that has been on the backhoe. Just in the last 10 or 15 hours the dipperstick cylinder (I believe) has started squealing when I extend or contract the arm. It sounds like metal on metal but all the zerks are loaded and the hydraulic fluid level is good. What else can it be? I don't want to cause any damage so it's just sitting idle now. And it's killing me. Help!!

I've had that same thing you are describing happen to me, too. At least the sound you describe sure sounds familiar. And in both cases it was the dipperstick cylinder. No doubt about where the noise was coming from. The noise was somewhere between a squawk and a squeal - but sure did sound like something metal to metal or else way too tight. It didn't do it every time the dipperstick was moved....maybe half the time. But it was clearly something going wrong so both times I removed the cylinder and took it to the hydraulic shop.

In each case it was that the O rings on the piston had gotten loaded up with a real fine dirt or dust, causing the O ring to be forced outwards and be too tight of a fit in the bore. The hydraulic mechanic said that it looked like a really hard claThere was no damage. Cleaning the groove and a new O ring fixed the problem completely.

Frankly I don't know why that happened - and I admit it doesn't make sense that yours has the same problem as mine with high hours.. Plus, one of my hoes had just spent a couple of years doing work out in the eastern wheat fields where there is a lot of dust...but how it got into the hydraulics is a mystery. The other one was also bought used and I don't know the history. Both machines had recently had filters and hydraulic oil changed. I'm sort of fanatic about filters and oil, so we use OEM hydraulic filters and high dollar hydraulic oil.

But what you are describing sounds exactly what I experienced. The sound is really distinctive. I first heard it from a hundred yards away because the hired operator was sort of playing with the sound and I found that I could too......sort of play with the sound, I mean..... - especially when the dipperstick cylinder was approximently horizontal.
The good news is that I was expecting a big rebuild cost, but it was just cleaning and O rings. No damage.
rScotty