Hello, I am using a two year old Kubota BX25 and have a hydrostatic question. All fluids have been changed at the correct intervals. Tractor has never been punished, always bullet proof. Was using it today to pull 8 inch logs. Climbed the hill to the woodlot as always two trips worth, and on the third it slowed and stopped mid climb. Was able to back it back down and head home. Checked out all connections underneath to make sure no linkages came apart. Tractor will move forward and backward until there is a load such as a climb. The minute the load comes on it slows and won't move at all. I can tell from the feel that things are spinning internally but no drive unless you are on flat going both forward and backward. Shifting it into rabbit gear it seems to have a little more pull but still won't even go up a small incline in the yard. No difference it you put you're heel on the diff lock. If you head up a steep incline in four wheel drive the fronts will start spinning but no drive from the rear. Jacking it up one side at a time everything feels connected in the diff. Jacked up all at once if one wheel is turned the other goes backward like I think it should. It's almost like there is a disconnect between the hydro and rear end somehow. No funny noises, no bad feel, just no drive. This will all happen right away even before it comes up to temp, fan underneath looks fine. Not easy to get it anywhere so I'm a bit freaked right now. Help!
BX25 No rear drive?
- Thread starter FREDGARVIN
- Start date
Welcome to the forum, and I'm sorry it had to start like this!
To clarify, are you saying that the entire drivetrain does not transmit full power to the ground, or just the rear end? You mentioned that the front wheels would spin- does it get full power to the front wheels? I don't know what the problem is, but isolating it is a big step.
To clarify, are you saying that the entire drivetrain does not transmit full power to the ground, or just the rear end? You mentioned that the front wheels would spin- does it get full power to the front wheels? I don't know what the problem is, but isolating it is a big step.
Full power seems to be available to the front. Looking at it tonight I get the feeling the diff, and or the diff lock has something to do with it. You can hold, by hand a rear wheel while it's running and hold it back. Diff lock pedal makes no difference. The diff lock pedal doesn't even feel like it's connected to anything. Not knowing what exactly is in there I'm simply guessing at all this. I can't believe I'm the only one that's experienced this. From everyone at different dealers I've spoken to, virtually they all say it's bullet proof, that it couldn't have had a failure internally but I wonder. I'm going to study the parts breakdowns tonight and try and figure out what does what. All linkages and pivots and the like are all intact and normal. Thank you for you're considerations.
All other hydraulics work fine. Everything has full power except the rear wheels. It's as if a clutch is slipping when the load is applied. You start up a small grade and when it has to work a little it slows and stops. Will always go on level ground, I'll bet I can even snow blow with it until I need to go up a grade.
Perhaps I have a reading disability......I read your posts again, and I see that I've AGAIN given you info that isn't what you asked for.....so, one more time....
Specifically, for hydrostatic transmission.....in the major section entitled "Transaxle".....
Charge Relief Valve...Setting Pressure....79.8 to 108.8 psi.....(oil temp at 122F)
High Pressure Relief Valve (forward and reverse).....Setting Pressure....2775 to 3190 psi...(oil temp 122F)
PTO clutch operating pressure...factory spec.....145.0 to 188.5 psi
These are the only pressure specs listed for the hydrostatic transmission (transaxle). No specs or references to pressure in/out of oil filter are given. Under "Oil Flow" diagram page, the following printed explanation of the circuit diagram of the hydrostatic transmission, if of any value to you....
"The pump and motor are joined in a closed hydraulic loop and most of oil circulates within the main oil circuit. A little oil lubricates and oozes out from the clearance between the moving parts of the case. Then oil in the main oil circuit of the HST needs to be supplied a want.
The oil from the power steering circuit flows into the HST for charging.
The charge oil aids smooth operation of pistons for pump and motor. The charge oil passes through the oil filter cartridge to charge relief valve port. The rest of oil passes through the charge relief valve into the HST housing., and overflow oil from HST housing return to the transmission case."
This is followed by pages illustrating oil flow for Neutral, Forward, Reverse, Relief (reverse).
http://www.tractorbynet.com/forums/...10753-bx25-transmission-circuit-pressure.html
My guess is......your relief valve.
You got it hot, went to bypass and got stuck or has failed.
North Idaho Wolfman
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Did I miss something
If the front wheels are spinning and the rear isn't then there is something broken inside!
If the front wheels are spinning and the rear isn't then there is something broken inside!
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Did I miss something
If the front wheels are spinning and the rear isn't then there is something broken inside!
Not if he can drive it on flat land, he does not have enough hydraulic pressure to operate under load.
He said that the front tires would spin, and later indictated that he was getting full power to the front wheels. Therefore, it sounds like the hydro is developing full power, but it isn't making it to the rear wheels.
I recall someone having a similar issue...
It turned out to be that the rear wheels were spinning inside the tires. Increasing the tire pressure somewhat solved the issue. Yeah, sounds strange !
To the OP... when you're experiencing the problem, just lean over the sides to look at the wheels and tires...
Pete
It turned out to be that the rear wheels were spinning inside the tires. Increasing the tire pressure somewhat solved the issue. Yeah, sounds strange !
To the OP... when you're experiencing the problem, just lean over the sides to look at the wheels and tires...
Pete
North Idaho Wolfman
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I know conflicting information!
What I didn't get was what you said,
"Perhaps I have a reading disability......I read your posts again, and I see that I've AGAIN given you info that isn't what you asked for.....so, one more time...."
Then after rereading a couple of times I realized it was a quote from another forums thread.
Had me confused why you were shouting at him?
I know conflicting information!
What I didn't get was what you said,
"Perhaps I have a reading disability......I read your posts again, and I see that I've AGAIN given you info that isn't what you asked for.....so, one more time...."
Then after rereading a couple of times I realized it was a quote from another forums thread.
Had me confused why you were shouting at him?
I should have put the quote in quotes........but there is a link.
Not me speaking......obviously now.......but the point is the pressure is divided off the pump and clearly the drive is separate from the other hydraulics with it's own relief valve.
But if it really is the tires..........moot.
North Idaho Wolfman
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lsmurphy, It is definitely good info!
We just need more clarity on what is or isn't happening with the tractor, and when it is or isn't happening.
We just need more clarity on what is or isn't happening with the tractor, and when it is or isn't happening.
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OMG, OMG OMG...Pete was right!!! Rims are spinning in the tires. Beet juice abounds. I couldn't see the rims from the seat and never even gave it a thought. It always seems to be the simple things. Thanks everyone!
"OMG, OMG, OMG" That is an appropriate reply to something like this. Congrats to you for not just thinking that it is not a possibility and not checking it out. Wow! If something has gone wrong with a tractor, someone on this board has had the same thing happen and knows a fix or a correct diagnosis.
While just adding air may help stop the problem, the best way to fix this is to take the tire/wheels to a tire shop and do the following;
1.break the tire bead from the rims.
2. apply a good tire seal to the bead
3. re-inflate to sit the bead.
The bead sealer provides just a bit of adhesion and prevents slippage as tire pressure varies. (note: some tire shops just use a water based lube (soap solution) as a mounting lube. It does not provide added sealing/adhesion.
Andre
1.break the tire bead from the rims.
2. apply a good tire seal to the bead
3. re-inflate to sit the bead.
The bead sealer provides just a bit of adhesion and prevents slippage as tire pressure varies. (note: some tire shops just use a water based lube (soap solution) as a mounting lube. It does not provide added sealing/adhesion.
Andre
North Idaho Wolfman
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WOW that came from out of left field! I would have never come up with that one!
How in the heck did the tire stay on the rims at all, do the BX's have such a short stiff wall tire that it could be flat and not de-bead itself?
If it were my tires, I'd be on the ground dragging the drawbar!
How in the heck did the tire stay on the rims at all, do the BX's have such a short stiff wall tire that it could be flat and not de-bead itself?
If it were my tires, I'd be on the ground dragging the drawbar!
85Hokie
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well hell, I never would have thought of that either.......bon of sitch !
bet that bead got a little warm too!
Now - I am running to look at my rears.........kick a tire or FOUR!
The dumbest thing of all is that last year I witnessed this when my neighbor was driving it and it never occurred to me this time. You're brain goes right for the hard stuff I guess. I don't know exactly what the crud is in the tires but I was told beet juice. It's reddish brown smelly stuff. It eats rubber tire valves I discovered through all of this. The metal insert came out of the rubber stem and covered me with the crap. This is the third time. I just replaced it with a metal stem from a motorcycle and hope it won't happen again. Very odd issues if you ask me. Thank you all again and especially Pete!