B7100 HST

   / B7100 HST #1  

snooks

Bronze Member
Joined
May 22, 2002
Messages
66
Location
Virginia, IL
Tractor
YM2500
I am looking at a Kubota B7100 HST with 5' belly mower. The tractor looks well maintained and has a little more than 1000 hrs. My only concern is the "roaring noise" it makes when the clutch is depressed. One guy said he thought that was normal for a hst. Can anyone verify this?
 
   / B7100 HST #2  
Jeff, it's hard to describe sounds with words, but I had a 1995 B7100 HST and no extra noise when the clutch was depressed. Personally, I'd suspect a bad bearing, but that's only a guess.
 
   / B7100 HST
  • Thread Starter
#3  
Bird, Thanks for the reply. Sounds are hard to describe, but this is loud enough that I don't think it came this way. The dealer doesn't normally deal in these tractors and he seemed puzzled by the noise. I know him well and if he knew he would tell me. Another guy on site said he thought it was normal.

Do you know if these tractors have "throw out bearings" like a vehicle with a manual trans? Is that something easy to replace? Just curious. Maybe someone else will shine some light on this issue. Thanks again Bird.
 
   / B7100 HST #4  
</font><font color="blue" class="small">( Do you know if these tractors have "throw out bearings" like a vehicle with a manual trans? Is that something easy to replace? )</font>

I bought mine new and traded up to a bigger one after putting about 400 hours on it, so never had to do any work on it. As far as I know it does have about the same throw out bearings, which is what I'd suspect the noise to be, and I understand it really isn't too big a job to change, but no personal experience. Like you said, maybe someone else can tell us more.
 
   / B7100 HST #5  
I just sold my B7100 a couple of months ago and can say that mine did not make any noise at all when pressing in the clutch. (1900+ hours) - I do have a service manual in front of me right now for this model tractor and it says it does have a throw-out bearing. I kinda remember one in there myself. Had to split in 2 to fix an oil leak once---Way easier than todays cars to work on though!
 
   / B7100 HST #6  
Snooks, If it is a loud roaring noise, then the tractor will have to broke in half to be fixed and run between $500 to $1000 to fix. I had a friend who sold his late father's 7100 hst to the local Kubota dealer and it did as you described. If you purchase be prepared to spend more based on my friend's experience.
 
   / B7100 HST #7  
If it has a clutch, it has a thowout bearing. I would say from many years of working on vehicles that it is gone. Try pushing down the clutch with your hand. You can then feel if the bearing is running rough or not. The vibration should be felt in the pedal also.
 
   / B7100 HST
  • Thread Starter
#8  
Thanks for all the great input. I went back and ran the tractor again and feel I need to clarify. The noise really isn't there until the PTO is engaged and before releasing the clutch. Once the clutch is released the blades begin turning on the belly mower and the noise goes away. When I clutch again to release the PTO, the noise is back until the PTO is disengaged. This almost makes me think its something other than a throw out bearing. I also notice there is a High and Low on the PTO. When in Low nothing happens. The blades and the rear shaft only move when the lever is all the way forward in the HIGH position. Maybe that will put a different light on the issue. Thanks again. You guys are great..... /forums/images/graemlins/cool.gif
 
   / B7100 HST #9  
That would be correct for a B7100. The high operates the 2500rpm mid pto and the high (960rpm?) rear pto at the same time. The low on the pto lever only operates the 540rpm rear pto.
 
   / B7100 HST #10  
If I know my B's, What you describe sounds to me like worn main shaft splines/pilot bearing. And to be brutally honest, unless you plan on spending an additional 2000 bucks minimum I'd pass on this tractor. The split with new clutch, shaft and bearing Is'nt too bad, but the basic truth is that if the pilot bearing (well actually it's not a bearing but a bushing) is worn and the previous owner let it go too long it will wear in to the end of the crankshaft and never be right without replacing the crankshaft and you know the $$$ goes up from there. There is a kit available to repair this problem on some B's/F's without replacing the crank but it would take a dealer with someone who cares enough to research it a little before replacing the crankshaft. I'm not sure if the kit I'm aware of would work with this unit. Either way your looking at a substantial repair.
 
 
Top