B7100 Pilot Bushing Help - Grinding Gears

ojaikubota

New member

Equipment
B7100
Sep 1, 2015
16
0
1
Ojai, CA
Our B7100 has for many years had a problem with grinding gears really hard coming in and out of gear unless you drop to really low revs. Never been able to change gear while moving. In 2016 the clutch failed and was replaced by a Kubota dealer. We use it about 10-20 hours a year, no more so I'm expecting the clutch should be OK. Dealer notes attached say they replaced clutch, bearings, seals and shaft (see photo). However, I believe the Kubota Part# is 66621-14120 BEARING DRY for the pilot bushing and don't see that on the invoice or a description saying pilot bushing. The grinding gears soon came back even with the new clutch. I've tried all the clutch adjustments from the manual and doesn't help. As mowing season fast approaches I did some research and am thinking I might have the pilot bushing issue where the bushing is gone and the hole in the flywheel (and shaft wear) will be too big for a replacement. I don't fancy splitting the tractor myself - is this too big a job to have the dealer do or is it time to retire the old B7100? Thanks in advance for the expert advice.
 

Attachments

ken erickson

Well-known member

Equipment
B7100 hst, 2650 front mount snowblower, L2501 hst qa loader
Nov 21, 2010
1,147
1,856
113
Waupaca Wisconsin
Our B7100 has for many years had a problem with grinding gears really hard coming in and out of gear unless you drop to really low revs. Never been able to change gear while moving.
This is gear drive and not HST? I could be wrong but if gear drive it would have non synchro transmission which would mean you should be at a standstill while shifting. I do not think it’s possible or practical to shift while moving and would imangine it would be extremely hard on the transmission etc.
 
  • Like
Reactions: 1 users

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,185
6,355
113
Sandpoint, ID
Like Ken said, that has straight cut, non synchronized gears, you must not be moving to switch gears.

If you can move around, have a good handful of tools and a flat spot. it's an easy DYI project.
WHat you find of the bushing and the shaft condition is anyone bet.
Other option is find a local mechanic.
A dealership is going to put the screws to you for this kind of repair.
 

ojaikubota

New member

Equipment
B7100
Sep 1, 2015
16
0
1
Ojai, CA
Thanks and dead right about the gear change. I'm thinking I have to remove the FEL and split the tractor to tackle the pilot bushing which isn't in my "easy DIY" range. Is there an easier way to do this. More importantly, do the symptoms suggest it is the pilot bushing? Thanks!
 

D2Cat

Well-known member
Lifetime Member

Equipment
L305DT, B7100HST, TG1860, TG1860D, L4240
Mar 27, 2014
13,816
5,557
113
40 miles south of Kansas City
You stated. " Never been able to change gear while moving."

As stated by other posters the square cut gears do not allow shifting while moving. Might try using your tractor by being in the gear you need to do the work with and not be shifting on the move and see what results you get. Maybe you're creating a problem you don't have!
 
  • Like
Reactions: 1 users

ojaikubota

New member

Equipment
B7100
Sep 1, 2015
16
0
1
Ojai, CA
I can confirm that the problem occurs going in and out of any gear while stationary. That's the only way I've been able to get in gear. Forward or reverse. I have to drop the revs as low as they can go and then it can go in gear - sometimes I need to release the clutch and press down again before it will go in gear. Does this sound like a pilot bearing problem?
 

st peter

New member

Equipment
l 2550
Mar 14, 2024
12
0
1
03867
I can confirm that the problem occurs going in and out of any gear while stationary. That's the only way I've been able to get in gear. Forward or reverse. I have to drop the revs as low as they can go and then it can go in gear - sometimes I need to release the clutch and press down again before it will go in gear. Does this sound like a pilot bearing problem?
 

st peter

New member

Equipment
l 2550
Mar 14, 2024
12
0
1
03867
welcome,you don.t wanna split if you don"t have to,I split a dual clutch l2550,Having trouble mating back up,gotta go in pretty level all around,front bolt jacks wilt wheels help,,but i used engine jack.Bottom line,not an easy job if you don.t have too don;t.I agree with the the boys shift at standstill like the 2550 model.Prob a 80 hour job, i was quoted $3000 +
 

jaxs

Well-known member

Equipment
B1750HST
Jun 22, 2023
734
522
93
Texas
From vibs I get from you I advise NOT DOING ANYTHING before trying to sell it to someone up to the challenge of diy repair. Just a wag but I'd estimate it bringing $1k to $2k depending on hours and cosmetic appearance. If you split it THEN SELL IT , you are looking at $200 to $500 for what we call a basket case. Since you must pay someone to split it you would go in the hole selling as a basket case. This site has a Buy,Sell Trade forum I recommend over most classifieds.
What do I think is causing gear grinding? I don't believe a worn pilot bushing would cause gear grinding in and of it self. Either throw-out bearing or improper clutch installation is more likely. As I recall this pressure plate requires "bench adjustment" before installation PLUS traditional adjustments required of all clutches after reassembly and on routine maintenance. It is the lack of bench adjustment that causes me to include improper installation as a possible cause. It's a sad state but in today's environment 9 out 10 shops thrive on gouging owners instead of earning an honest living. I realize I've painted a discouraging picture but on the bright side if you decide to spilt it you can rely on OTT members to answer question and supply resources as needed if you furnish the determination.
 

North Idaho Wolfman

Moderator
Staff member
Lifetime Member

Equipment
L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Jun 9, 2013
30,185
6,355
113
Sandpoint, ID
I can confirm that the problem occurs going in and out of any gear while stationary. That's the only way I've been able to get in gear. Forward or reverse. I have to drop the revs as low as they can go and then it can go in gear - sometimes I need to release the clutch and press down again before it will go in gear. Does this sound like a pilot bearing problem?
It could be the pilot bearing but that's a wildcard, or more likely could be a clutch finger adjustment issue.
How far do you have to push the pedal down before it stop putting power to the wheels?
 

DustyRusty

Well-known member

Equipment
2020 BX23S, BX2822 Snowblower, Curtis Deluxe Cab,
Nov 8, 2015
6,237
4,816
113
North East CT
I can confirm that the problem occurs going in and out of any gear while stationary. That's the only way I've been able to get in gear. Forward or reverse. I have to drop the revs as low as they can go and then it can go in gear - sometimes I need to release the clutch and press down again before it will go in gear. Does this sound like a pilot bearing problem?
No, it isn't a pilot-bearing issue that you have, but an understanding of your tractor. You are thinking of the tractor the same way you would drive a car. Tractors are not cars, and you don't shift gears on a tractor when it is in motion like you would with a car. You pick the gear that you want for the job that you are doing, and you start and finish using that gear. If the tractor is at a high idle, then the idler gear is spinning too fast to mesh with the other gears in the gearbox. You should only be switching gears when the engine is at a slow idle or even stopped. The only thing that you might try is changing the gear oil in the gearbox to a lighter-weight gear oil. Check with your tractor's manual to see what is recommended.
 

GreensvilleJay

Well-known member

Equipment
BX23-S,57 A-C D-14,58 A-C D-14, 57 A-C D-14,tiller,cults,Millcreek 25G spreader,
Apr 2, 2019
11,401
4,899
113
Greensville,Ontario,Canada
1st, don't know why dealer didn't replace the pilot bearing while it was split.....have to assume they inspected it and said it was OK.

2nd, grinding gears while stopped sounds like engine is still spinning the clutch, not 100% disengaging

3rd, grinding gears for years. wow. I'd split and inspect EVERY gear in the transmission as well as the shifter forks. I suspect there to be damage in the tranny.

4th, splitting tractor is easy,having extra hands help,key is concrete floor ,good lighting and patience.
 

PaulL

Well-known member

Equipment
B2601
Jul 17, 2017
2,432
1,361
113
NZ
To summarise:

1. Your description says that you get grinding gears if you change when moving. You can only change gears when stationary, and even then you sometimes have to release the clutch and try again

2. There is some suggestion that it got worse recently, but it's not clear really what about it got worse

3. If that's the full description, then the other commenters are correct. That is expected behaviour, it's how it's supposed to work. They're straight cut gears with no synchro. That means you can't change when moving, and even when not moving you sometimes have to have a few goes at it before it goes in.

So, if that's all of it, then it's great news. You have no need to do anything, other than stop trying to change gears whilst moving.
 

Mountainman

Active member
Lifetime Member

Equipment
L2501, B7100, B6000, B21, B1750, B2400, B7200
Jul 10, 2022
226
80
28
Attalla Alabama
mossycreekoutdoors.com
Do you feel vibration when you depress the clutch pedal. Worn out bushing can cause it not to be able to switch gears while stationary (not made to switch while moving but that's already been covered). What happens is the bushing keeps the shaft straight. When that is worn now your shaft can wobble and the clutch disk is hitting the pressure plate ans flywheel creating vibration and enough spin on the shaft to make it grind when switching gears. If no vibration then I wouldn't suspect bushing.
 

Henro

Well-known member

Equipment
B2910, BX2200, KX41-2V mini Ex., Beer fridge
May 24, 2019
5,781
2,965
113
North of Pittsburgh PA
To summarise:

1. Your description says that you get grinding gears if you change when moving. You can only change gears when stationary, and even then you sometimes have to release the clutch and try again

2. There is some suggestion that it got worse recently, but it's not clear really what about it got worse

3. If that's the full description, then the other commenters are correct. That is expected behaviour, it's how it's supposed to work. They're straight cut gears with no synchro. That means you can't change when moving, and even when not moving you sometimes have to have a few goes at it before it goes in.

So, if that's all of it, then it's great news. You have no need to do anything, other than stop trying to change gears whilst moving.
I believe the OP said that he gets grinding when the tractor is not moving… In a post that followed his original post.
 

motorhead

Active member

Equipment
2009 B3200, 2007 Dodge/Cummins powered Ram 2500 395hp
May 17, 2012
441
34
28
Atascadero
I can confirm that the problem occurs going in and out of any gear while stationary. That's the only way I've been able to get in gear. Forward or reverse. I have to drop the revs as low as they can go and then it can go in gear - sometimes I need to release the clutch and press down again before it will go in gear. Does this sound like a pilot bearing problem?
Seeing that you have the clutch all the way in and have to let it out for a second and push it back in to get it in gear, tells me that the clutch disc is completely stopping. I have to say that you don't have anything hanging up in the clutch or pilot bearing, you just have a transmission with NO synchros and square cut gears for strength. To be honest, I owned a B5100D, that's the nature of the beast.
 

Henro

Well-known member

Equipment
B2910, BX2200, KX41-2V mini Ex., Beer fridge
May 24, 2019
5,781
2,965
113
North of Pittsburgh PA
Seeing that you have the clutch all the way in and have to let it out for a second and push it back in to get it in gear, tells me that the clutch disc is completely stopping. I have to say that you don't have anything hanging up in the clutch or pilot bearing, you just have a transmission with NO synchros and square cut gears for strength. To be honest, I owned a B5100D, that's the nature of the beast.
Simple question. Never owned a gear tractor.

Wouldn't one realize that the gears didn't engage when they manually shifted to a different gear?

And if the gears did not engage, wouldn't it be normal to put the lever back into neutral and then let the clutch out and put it back in and try again, to see if the gears did engage?

Maybe I'm missing something, or maybe the OP is doing something differently than I imagine I would if I had the gear tractor…
 

jaxs

Well-known member

Equipment
B1750HST
Jun 22, 2023
734
522
93
Texas
Our B7100 has for many years had a problem with grinding gears really hard coming in and out of gear unless you drop to really low revs. Never been able to change gear while moving.
I can confirm that the problem occurs going in and out of any gear while stationary. That's the only way I've been able to get in gear. Forward or reverse. I have to drop the revs as low as they can go and then it can go in gear - sometimes I need to release the clutch and press down again before it will go in gear. Does this sound like a pilot bearing problem?
OP has stated THIS TWICE so shifting on the fly doesn't require consideration and only muddies up the water distracting from actual symptoms under real world conditions. Problems "coming out of gear" while standing still is a key clue. It sounds like dealer fumbled the ball in not making p plate adjustments before reassembling tractor.
 

fried1765

Well-known member

Equipment
Kubota L48 TLB, Ford 1920 FEL, Ford 8N, SCAG Liberty Z, Gravely Pro.
Nov 14, 2019
7,843
5,066
113
Eastham, Ma
Simple question. Never owned a gear tractor.

Wouldn't one realize that the gears didn't engage when they manually shifted to a different gear?

And if the gears did not engage, wouldn't it be normal to put the lever back into neutral and then let the clutch out and put it back in and try again, to see if the gears did engage?

Maybe I'm missing something, or maybe the OP is doing something differently than I imagine I would if I had the gear tractor…
I have owned a geared tractor for 51 years.
It is simple.
You select a gear, and then add power, while letting the clutch out.
No shifting/changing of gears is possible, while the tractor is moving!
 
  • Like
Reactions: 1 user