B2650 Do Hydraulic Pumps Quiet Down After Broken In?

   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #1  

Utopia Texas

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Aug 11, 2013
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754
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Brookshire & Cat Spring,Texas
Tractor
Kubota B2650 / Kubota L6060 / Kubota ZD2300
Have had my B2650 with cab for two days and compared to the 21year old Ford 1215 I traded in this unit is really loud! Both have the HST transmission. Borrowed a decibel meter from a neighbor and at 2400 rpm standing still the engine puts out 67db but when the HST is engaged and riding in the pasture the sound goes up to 85db. I always wear hearing protection when using ANY machinery since I have been wearing hearing aids for years, but this level to me is way into permanent hearing damage range. Will the pump quiet down when broken in or is this normal for Kubota? My NH T4.75 which is 75 hp is not even this loud at WOT. Yes, the hydraulic fluid level in thr B2650 is at the correct level. Thanks....
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #2  

diesel85

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Jun 7, 2017
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1,006
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Vernon, NY
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Kubota BX2200
That's odd. My BX2200 is pretty quiet in terms of the HST transmission. However the engine itself is loud. Seems like the smaller Kubota tractors are loud and the NH tractors are quiet across the board. My neighbor has a TC35 and even at WOT it is no louder than my truck.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #3  

PaPow

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Jun 4, 2017
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651
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NY
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Kubota BX23S
Personally, i think kubota has the loudest HST`s of any other ones out there today. And if you have a enclosed cab, it seems even worse.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #4  

CHDinCT

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Conn. & Florida
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Kubota BX25, Z422-KW
Had the same experience when I test drove a cabbed 2650 a few years ago. I thought the brake was stuck on or something. Only drove that one unit so can't say if they're all that way, but seems you're the first in a while to also complain.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #5  

PaPow

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651
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NY
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Kubota BX23S
Had the same experience when I test drove a cabbed 2650 a few years ago. I thought the brake was stuck on or something. Only drove that one unit so can't say if they're all that way, but seems you're the first in a while to also complain.

Chris,
i wasn`t really complaining about it, i just notice they seem a little noisier than other brand HST`s i`ve driven.
The hydraulic pump whine dosen`t bother me at all, i rather enjoy hearing it... its just like music to me...lol
The way i look at it is, ya can`t do anything about it, so you learn to live with it and naturally block it out.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #6  

mpham

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Oct 8, 2011
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1,085
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North/central Massachusetts
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Kubota B 2650 cab
Mine seems like it is twice as loud as my Kioti was.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #7  

CHDinCT

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Conn. & Florida
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Kubota BX25, Z422-KW
Chris,
i wasn`t really complaining about it, i just notice they seem a little noisier than other brand HST`s i`ve driven.
The hydraulic pump whine dosen`t bother me at all, i rather enjoy hearing it... its just like music to me...lol
The way i look at it is, ya can`t do anything about it, so you learn to live with it and naturally block it out.
Oh, i feel the same as fsr as my BX25 goes, but that B2650 cab tractor was much louder than any BX I've heard.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #8  

JOHNTHOMAS

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Apr 14, 2008
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7,720
Location
Somerset, Ky
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F2690 4WD RTV X1140 MX5400 HST ZD1211
I believe my B2650 was a bit louder than some of my other HST Kubotas and sure it would be amplified in a cab. Course all Kubota HSTs that I've owned have the HST whine with giving increased go juice/hydraulic fluid with the floor pedal.
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #9  

rScotty

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Apr 21, 2001
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6,231
Location
Rural mountains - Colorado
Tractor
Kubota M59, JD530, JD310SG. Restoring Yanmar YM165D
Have had my B2650 with cab for two days and compared to the 21year old Ford 1215 I traded in this unit is really loud! Both have the HST transmission. Borrowed a decibel meter from a neighbor and at 2400 rpm standing still the engine puts out 67db but when the HST is engaged and riding in the pasture the sound goes up to 85db. I always wear hearing protection when using ANY machinery since I have been wearing hearing aids for years, but this level to me is way into permanent hearing damage range. Will the pump quiet down when broken in or is this normal for Kubota? My NH T4.75 which is 75 hp is not even this loud at WOT. Yes, the hydraulic fluid level in thr B2650 is at the correct level. Thanks....

In answer to the first part of your question, "Will the pump quiet down when broken in or is this normal for Kubota?"

Hate to say this, but unless something is wrong with the pump clearances, I doubt it will become any quieter as it is broken in. My guess is that it won't change much at all.

We know that hydraulic pumps are made very accurately with tight clearances. It would be rare for the internal clearances to be inaccurate, but possible of course. Anyway, in a normal hydraulic pump the whine is least when it is new and tends to increase with wear. In fact, when a pump begins to make a lot of whine it means something is not right - wrong fluid, wrong fluid level, or worn parts.

First things first though - and luckily any small change in pump whine pitch or amplitude can result in way less resonance within the cab. So it's worth looking at how the pump is mounted to see if you can improve the damping of the pump vibration before it begins to excite the cab. I've heard all kinds of stories about damping vibration out by using flex arms and weights bolted to the case to soak up vibration. Mechanically that makes sense, but I've never done it myself. I did improve one hydraulic pump by tightly wrapping the most active part of it's case with insulation and duct tape. Big improvement.

As to the second part of your question, "...is this (whine) normal for Kubota?"
I can't help much there as I'm comparing to other tractors rather than to other Kubotas. None of my tractors makes much of a hydraulic whine, but that may just be because I tend to run at low RPM. My own preference is to set the throttle for minimum noise instead of maximum power.

Here's one idea that may help, though. At the first service, you might want to try a different fluid. Our Kubota M59 came with New Holland -Ambra Multi G 134 hydraulic fluid from the dealer. After a few hundred hours I got curious enough to switch oil and filters over to try Kubota's new SUDT hydraulic fluid. Well, the SUDT definitely increased the whine. Maybe it was just our particular machine, but the HST whine changed from being barely noticible all the way to being hard to ignore. In fact, it increased it so much that within the month I kissed a few hundred dollars goodby and switched back to the NH fluid. That put things back to normal, so apparently no harm done.
That experiment kind of surprised me. My expectation was that different oils would sound more or less the same in the pump. Not so.

Also interesting is that on the NH website their Multi G 134 is rated as a general purpose trans/hydraulic fluid, rather than being one of their severe duty fluids. I have no idea what that really means, but the 134 worked for us. Might be worth a try with yours.
luck,
rScotty
 
   / B2650 Do Hydraulic Pumps Quiet Down After Broken In? #10  

100 td

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Aug 29, 2015
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474
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ɹǝpunuʍop
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Kubota B21TLB (B21, TL421, BT751) Toyota SDK4, T116 Bobcat
Our Kubota M59 came with New Holland -Ambra Multi G 134 hydraulic fluid from the dealer.
I'm interested to find out about ANY oil that runs quieter!
I would have thought they come factory filled with Kubota oil so they can be driven/moved from transport, perhaps not?
I wouldn't have thought a dealer would fill with a universal tractor transmission oil instead of Kubota specified fluid, (and expecting that everything has oil from factory), a change in fluid?
 
 
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