B2920 HST Creaking Sound

BrierPatch · May 22, 2011

My B2620 makes the exact same sound as your tractor. I called it a ratcheting sound. It only does it when it is under a load. I don't know if it is a bypass or pressure relief thing. Do you feel that your tractor rolls easier than it should when on a slope? I have had several hst tractors and none of them roll as easy as my B2620. I am very interested to see what you find out. I tried to show my dealer, but was unsuccessful in convincing them of anything. My warrenty ends this summer I may have to try again. Just to let you know mine has done it since new and at 130 hrs has not changed.

bp fick · May 22, 2011

Add another. My B2320 makes that same sound when I really, really pull hard, such as running my middle buster. It doesn't make it just driving around as yours does. Nonetheless, the sound is identical. I agree with BrierPatch. Describe it how you wish. Clattering. Ratcheting. Chattering. Whatever. I'll be interested to see if anyone can figure this noise's source.

It's gotta be in the hydro, at least mine is, as it does not seem to be coming from the engine compartment. I too suspect a control or relief valve of some kind.

OrangeRidge · May 22, 2011

This is one for an Owner Survey . Has this sound been mentioned by
others since the model was released ?

bp fick · May 22, 2011

I'm game to try just about anything mechanically and have all the proper tools in my shop.

Well, I'm all for adjusting a relief or whatever, but do not have the shop manual and I'd be shooting completely in the dark. Apparently, this has nothing do with which engine one gets, according to the last few posts, but seems common to the 20 series. Anybody got any guidance of this?

bp fick · May 22, 2011

http://www.tractorbynet.com/forums/kubota-owning-operating/115836-b7610-squealing-noise-2.html

Here's an earlier thread that sounds eerily familiar. I am going to check this out and see what there is to see. It sure cannot hurt. Even the B3030 guys chimes in, so it sounds a little like this may be an issue on several Kubota models dating back awhile.

Hey, it's a place to start anyhow. Drive shaft boot.

BrierPatch · May 22, 2011

I don't have to work mine hard at all for it to make the sound, just like in the video. Simply going up slight hill.

I plan on getting a shop manual for mine. I was waiting until the warranty was up so I didn't get over anxious and start working on it and void the warranty.

e171fish · May 22, 2011

Just checked the drive shaft boot. No dice.

bp fick · May 22, 2011

e171fish said:
Just checked the drive shaft boot. No dice.

I just crawled under mine and identified the drive shaft boot. I did not take the time to loosen the keeper bolt and grease it up, as mentioned in that old thread. I intend to do this tomorrow. The sound complained about in the old thread might be an entirely different, who knows.

For sure, greasing and adjusting that boot sure isn't going to void any warranty.

bp fick · May 23, 2011

Time for an update. I loosened the keeper clamp on the drive shaft cover and slid it back. I lubed the shaft and u-joint, and put the cover back on. Whatever sound guys in earlier threads attributed to that cover, it is not the source of this particular chattering.

Warmed up my tractor and did some mowing. When I was finished, I made the tractor bare to do some testing. I can not generate the sound at idle. I cannot make the sound in Lo gear just driving around. I cannot make the sound in Medium just driving around. I can however get a bit of it when taking off in High. Since I definitely get the ratcheting clatter when pulling hard with the plow, I am quite certain it is the HST.

This must be some kind of protective relief valve or pressure device. That I can replicate precisely the same sound under duress, it suggests that, while annoying, the sound is relatively normal on my machine, most likely, although I think it is set too sensitive.

This logic also suggests, however, that if your relief valve/device is clattering at idle, or under "normal" operation, that it is set far too sensitive or is not working properly. Does that makes sense? I hope so.

Surely, a good tech or Kubota themselves know which of their devices emits this gawd-awful noise? They've gotta know.

OrangeRidge · May 23, 2011

bp fick said:
This must be some kind of protective relief valve or pressure device. That I can replicate precisely the same sound under duress, it suggests that the sound is relatively normal on my machine, most likely, although I think it is set too sensitive.

This logic also suggests, however, that if your relief valve/device is clattering at idle, or under "normal" operation, that it is set far too sensitive or is not working properly. Does that makes sense? I hope so.

Makes sense to me . Now for someone with a WSM for B##20

BrierPatch · May 23, 2011

Thanks BP. Appreciate your help and troubleshooting on this.

Good Job ! :thumbsup:

Creek44 · May 23, 2011

My opinion of the offending noise after 100hrs of use has been that it is of HST origin and that it is a normally abnormal manifestation of this particular model.

jambx · May 24, 2011

Your U-Tube was great - made me feel I was not alone - I am at 140 hours and the exact noise is still there most when under load - I have never been able to isolate it - since other owners too hear this sound I am begining to think its just normal HST whine for the 2X20's

When I think back to my origional BX22 - that baby just purred at all speeds when compared to this B - although I a still very happy with this platform.

Here was my thread back in 2009;

http://www.tractorbynet.com/forums/kubota-owning-operating/145409-b2920-vibration-under-load.html

bstrom · May 24, 2011

I've got a 2008 B2620 with around 240 hrs on it. I've used it pretty hard at times and never noticed this noise so I don't think it's normal I'm sorry to say. The only thing I did maybe different than normal is change the HST oil at around 50 to 60 hrs but I doubt that's it. I also did not run it fast or hard the first 50 hrs but I'm sure most people do that I guess.

Also mine does not roll easily on slopes, especially in 4 wheel drive. What about something wrong with the diff lock or the L-M-H gearing or clutch adjustment? I don't know what, just wild guessing because it's a clattering sound.

bp fick · May 24, 2011

Even if, if it is "normal" under heavy load, how can it be normal when just driving around? Nope. Not ready to accept that such a ratcheting racket is normal with the OP just driving around. $.02

BrierPatch · May 24, 2011

bstrom said:
I've got a 2008 B2620 with around 240 hrs on it. I've used it pretty hard at times and never noticed this noise so I don't think it's normal I'm sorry to say. The only thing I did maybe different than normal is change the HST oil at around 50 to 60 hrs but I doubt that's it. I also did not run it fast or hard the first 50 hrs but I'm sure most people do that I guess.

Also mine does not roll easily on slopes, especially in 4 wheel drive. What about something wrong with the diff lock or the L-M-H gearing or clutch adjustment? I don't know what, just wild guessing because it's a clattering sound.

I was concerned enough about mine that instead of doing the 50 hr service myself I had the dealer do it so there was no chance of it being something I did. However this is when I was unable to convince them of the problem also.:confused2: I also tried to break it in by not running it hard or constant speed/rpm for extended periods and not running it full throttle.

donn12 · May 24, 2011

I am pretty sure mine makes a similar noise when in high gear but I do not use high very often. I have always thought it was normal.

wowwee · May 24, 2011

I have a B2320, it makes the same noise. I have 60 hours on it now. I never noticed the noise until a few months ago when moving snow. Noise only happens under load, doesn't always have to be a heavy load. First time I heard it I immediatly thought it sounded like a hydrostatic transmission noise. Hope it stays the same for another 3000 hours, or even better, self destruct while it's in warranty.

Dale

chriscos · Jun 5, 2011

i have a 2920. Mine makes the same noise when I have the rpms set too low, or I am pushing into a huge pile, but I don't seem to recall it making this noise "normally", or better yet, it doesn't make that sound when I don't expect it to.

To me, it sounds like my HST when I am "bogging it", For example, if I have the RPM set too low.

Did you have the go pedal all the way down in the second video? Does it make that noise with the go pedal all the way down at full RPM?

It might not be pressure relief, but instead, the sound of the fluid going through valves that are not open all of the way?

I'll experiment some more, but one thing to keep in mind, if you are running at full RPMs you might as well press that pedal to the floor, since you are burning the fuel anyway

I don't like to run at full throttle if I don't have to.. and now that I think about it, I make my gear/RPM choice based on not having to hear that sound.

My $0.02...

ackerrj · Jun 6, 2011

chriscos said:
i have a 2920. Mine makes the same noise when I have the rpms set too low, or I am pushing into a huge pile, but I don't seem to recall it making this noise "normally", or better yet, it doesn't make that sound when I don't expect it to.

To me, it sounds like my HST when I am "bogging it", For example, if I have the RPM set too low.

Did you have the go pedal all the way down in the second video? Does it make that noise with the go pedal all the way down at full RPM?

It might not be pressure relief, but instead, the sound of the fluid going through valves that are not open all of the way?

I'll experiment some more, but one thing to keep in mind, if you are running at full RPMs you might as well press that pedal to the floor, since you are burning the fuel anyway

I don't like to run at full throttle if I don't have to.. and now that I think about it, I make my gear/RPM choice based on not having to hear that sound.

My $0.02...

I have a B2320 with 13 hrs on it that does not make that noise even under load. Your noise does sound like a vibrating heat shield. I have run mine at 2600 rpm with a 400 lb king kutter rotary mower, no unusual noises. Also under heavy load doing subsoiling. The noise there sounded like hydraulic fluid under pressure, kind of a wooshing noise. Dealer assured me this was normal HST noise under load.