PLEASE HELP!!! mower bogs down badly...

[lotp32]

heres the deal, i know im new here but im pulling my hair out. nobody seems to have an answer for me.

I have a gr2120 diesel mower. 4x4, hydrauilics, all the bells and whistles for a garden tractor. my problem is that the thing will not mow normally.

heres what i know and what ive tried. new blades, every speed imaginable, every adjustment to the deck possible, tried mowing at different times of the day (insuring dry grass), all normal maintenence has been performed and is up to date.

heres the details. even at max throttle, with the deck at 3 inches, the deck will bog down to the point of stopping if the grass is the slightest bit thick. i have to constantly raise and lower the deck depending on how green the grass is. if i raise it high enough to not bog it down, its not even cutting anything and i have to go over it again. if i drive the tractor at a snails pace, it will barely make it through (still bogs down but doesnt stop all together)

i also noticed that the actualy gear box on the deck and the belt itself isnt the problem, the problem seems to stem from the transaxle/rear end as the pto from that portion that turns the deck is whats actually stopping.

the motor itself does not bog down at all and for what its worth, i seems to mow fine if im going in reverse. not sure what that means...


somethings just not right, and its a problem that seems to have slowly gotten worse over the past 2/3 years.

is there something im missing? is there an adjustment with the transaxle that can be made to send more rpms or more power to the pto? or could there possibly something else im missing?

any help would be GREATLY appreciated, spent $7500 on this mower 4 years ago and expected to have this mower for a decade and so far it has only 135 hours on it.

 

[lotp32]

actually, its a 2110. my bad, 2008 model...

 

[Stumpy]

I know nothing about that machine but that sounds like symptoms of a slipping clutch or stripped spline. Though with a boogered spline you'll usually get this lovely clacking sounds as it slips. Also since that's a hydrostatic machine the PTO is usually hydraulically driven separately from the transmission.

Let me ask this, to engage the deck do you throw a electrical switch or move a hydraulic valve? Either way this doesn't sound like an easy fix, is it still under warranty?

 

[lotp32]

I know nothing about that machine but that sounds like symptoms of a slipping clutch or stripped spline. Though with a boogered spline you'll usually get this lovely clacking sounds as it slips. Also since that's a hydrostatic machine the PTO is usually hydraulically driven separately from the transmission.

Let me ask this, to engage the deck do you throw a electrical switch or move a hydraulic valve? Either way this doesn't sound like an easy fix, is it still under warranty?

its a hydraulic valve and its not under warranty. im just so frustrated, i wish i would have complained about it from the beggining but i just thought i was doing something wrong. a few summers worth of tweaking and nothing has changed and now im out of warranty and seriously stressed.

i honestly believe its a clutch problem but i didnt know if there was a way to adjust the clutches or if there was a possibility of some sort of air bubble in the hydraulic lines that might need bleeding? i dont know much about hydraulics and at this point im just grasping at straws...

 

[Kytim]

Air tends to remove itself after a few cycles as oil flows under pressure through the suction line back to the reservoir. About the only place air gets trapped is dead end lines / single acting cylinders.

 

[Stumpy]

Hummm.... I just don't have enough experience with those hydraulic systems to be of much help. Send a PM to Service Dept Vic. Click the send message drop down menu beneath his name on that page and click the middle one. Ask nicely and explain clearly, he's a busy guy. He does this for a living and knows more than most of us combined. If anyone around here can give you an answer without taking it apart he can.

 

[Istrian]

Greetings from New Zealand. I've now done just on 50hrs on my new GR2120 52" deck. I am amazed at the power of this machine and have no problems cutting tall, tough grass. If you know "KIKUYU" grass you will know just how tough that stuff is. Yes I do have to take it slowly on the thickest parts. The only times the mower starts to object is when the discharge shute is blocked (by adjacent tall grass - hence can't discharge). Are you sure that your mower does not have a "mulching deck". I know that these machines were supplied with either the regular side discharge, or a mulching deck. Reading the symptoms you describe makes me think you have a mulching deck which will not cope well and is not designed to cut tall grass.

 

[lotp32]

Greetings from New Zealand. I've now done just on 50hrs on my new GR2120 52" deck. I am amazed at the power of this machine and have no problems cutting tall, tough grass. If you know "KIKUYU" grass you will know just how tough that stuff is. Yes I do have to take it slowly on the thickest parts. The only times the mower starts to object is when the discharge shute is blocked (by adjacent tall grass - hence can't discharge). Are you sure that your mower does not have a "mulching deck". I know that these machines were supplied with either the regular side discharge, or a mulching deck. Reading the symptoms you describe makes me think you have a mulching deck which will not cope well and is not designed to cut tall grass.

im not sure if i have a mulching deck or not, i do have a side discharge and early on i lifted the guard with a bungee cord to keep from grass building up.

i talked to both the service manager at the dealer and a service guy at kubota, they both seem to think its a pto clutch problem. it was innevetible, i was certain it was something major but i didnt want to believe it. dealer is coming monday to pick it up.

this sucks..., although, kubota said they could do a partial warranty if my dealer says they should. hope so because it doesnt seem like an easy job...

 

[Orange Tractors]

I know you said it only has 135 hours on it, and the problem has been gradually getting worse for the last 2/3 (or is it 2 to 3?) years.

Have you ever changed the hydraulic filter and fluid? If everything on the tractor is hydraulically driven, and an additional load causes the PTO and tractor movement to stop, but doesn't stall the engine; look to the fluid flow -- hyd pump/ filter/ valves/ hyd motor, etc..

I try to look for the simple and cheap fixes first.

Robert

 

[kuboman]

I know you said it only has 135 hours on it, and the problem has been gradually getting worse for the last 2/3 (or is it 2 to 3?) years.

Have you ever changed the hydraulic filter and fluid? If everything on the tractor is hydraulically driven, and an additional load causes the PTO and tractor movement to stop, but doesn't stall the engine; look to the fluid flow -- hyd pump/ filter/ valves/ hyd motor, etc..

I try to look for the simple and cheap fixes first.

Robert

You should get the hydraulic pressure tested. The small Kubotas do not have a dedicated hydraulic pump. They use the charge pump for the hydrostat for the hydraulics. It may be weak or the pressure relief may need to be set up. Other than that you could have a leak in the pto clutch pack. Start with the cheap and simple first.

 

[Kytim]

I'm gonna annotate this story merely because of its merit but not direct correlation to the problem.

I was having an issue with my B7100 bogging down while mowing one day. I use my 7100DT with a quick hitch on my 3ph 99% of the time. So I was mowing with my RM360 woods finish mower in grass that was just a slight bit taller than normal. I just couldnt understand why I was blackstacking smoke so bad and slowing the engine and mower RPM's. I checked fuel quality (water), tire inflation, blade sharpness and obstructions, air filter blocked, etc. It was so bad I really couldn't mow. after looking for quite a while I finally found it. When I started I set the mower down & I pushed the 3ph control valve handle all the way forward. This allowed the QH to sit atop the prop shaft safety tubing causing friction enough to slow the engine and finally melt the tube halves together! Moral: don't overlook the simple things!

 

[davemskinner]

Hey lotp - any updates as to what the dealer found? We'd love to know!

 

[lotp32]

Hey lotp - any updates as to what the dealer found? We'd love to know!

well, after deciding to live with the problem for another season and deciding to sell/trade it after this year, i mowed with it one more time and i just couldnt bare it any longer.

after alot of thought, i gave it one more shot. i took the cover off it, saw that the lever that opens and closes the hydraulic valve was adjustable. i took the wheel off to get access and i made about a 1/2 inch adjustment on the lever. i noticed an immidiate difference even before i mowed with it. the deck went full bore instantly where as before it took a few seconds for it to get up to speed.

i reckon that the valve wasnt opening fully even if it was only by fractions.

i put the wheel back on and went to work. issue is 100% resolved and i feel ultra relieved.


thanks for all the help everyone....

by the way, this all just happened an hour ago...

thanks again.

 

[Stumpy]

I just love problems like that. A set of strange symptoms with no simple diagnosis and it turns out to be something simple like that. Thanks for updating, now we now what to recommend when someone else has that problem.

 

[Apogee]

lotp32,

"and deciding to sell/trade it after this year"

Glad you got it fixed!

Hopefully, you will do a "reset" and give it another chance to earn your respect. Sounds like it was just mis-adjusted from day one...

Now that it's fixed (good sleuthing job by the way), I believe you will find the Kubota a workhorse that you won't want to give up.

I also think its admirable that Kubota was willing to stand behind it even out of warranty by a few years.

Best of luck with your "new" mower,

Steve

 

[lotp32]

lotp32,

"and deciding to sell/trade it after this year"

Glad you got it fixed!

Hopefully, you will do a "reset" and give it another chance to earn your respect. Sounds like it was just mis-adjusted from day one...

Now that it's fixed (good sleuthing job by the way), I believe you will find the Kubota a workhorse that you won't want to give up.

I also think its admirable that Kubota was willing to stand behind it even out of warranty by a few years.

Best of luck with your "new" mower,

Steve

its funny you say that. i told my wife that it seems as if it was never adjusted properly from the beggining because i dont ever remember it mowing as well as it is now. even stranger is that the adjustment nuts were tight so it doesnt seem if it was slowly working itself out of adjustment. i just hope i didnt do any longterm damage to any clutches by running it like that for such a long time...

 

[Apogee]

Since it was a hydraulic valve that you adjusted, I'd be very surprised if there was any damage done. Sounds like it was simply not getting enough flow.

*I'm guessing here* but my bet is the PTO clutches are slip clutches to protect the drivetrain in the event you hit something and it suddenly stops the blades. They're not for engaging the drive like what happens on a manual transmission car for example. The clutch is basically engaged all of the time and the starting and stopping of the blades is handled hydraulically. Hence, I wouldn't worry about having worn anything out prematurely as I don't think that's the case. It not getting enough flow didn't hurt a thing besides your frustration level.

Again, enjoy your "new" mower! Make sure to keep up on the maintenance and continue to take care of it (like you already have). I'd start thinking about replacing it around the 3000 hour mark - yes, I'm serious!

Most of all, have fun!

Best,

Steve

PS - The "green" ones aren't any better made, don't last any longer, and you would be hard pressed to find something as tough as that little diesel you've got!

 

[kuboman]

Have you checked your hydraulic filters? I would change them and then cut them open and check for black paste. They would have been slipping and have worn.

 

[Orange Tractors]

Like I said, check the simple and cheap stuff first.

Glad you got it fixed.

Robert

 

[QTipsGirl]

Hi Lotp32....
I know it's been a few years since you did this repair, but my GR2100 is doing the exact same thing and I have replaced the deck belt and fuel filters, I have fairly new blades and they are sharp, but it is still bogging down to the point of uselessness.

Can you explain in more detail where and how you made this adjustment? I have a workshop manual for my model but am not sure which hydraulic valve lever you are talking about. Is it the one that engages the blades?

Thanks in advance