B6100 High Range Issue

[Ban One]

Hello everyone, I've been a regular reader here for quite some time and used the wisdom of members recommendations many times on other projects by reading your posts, but I'm at a stand still on my latest project. Have a B6100 HST 2WD hydro that doesn't pull itself at all on a steep grade and barely on a small grade and fine on flat ground, but seems to pull pretty good in low gear on any terrain. Let me fill you in on what I've done so far. When I got the tractor and it posed the same conditions as stated above but clutch release bearing was sounding awful, so I thought I would change clutch, pressure plate and bearing all at the same time thinking the clutch was slipping. Had flywheel resurfaced, which only needed minimal work to true up. Put back together, clutch worked great, but still the same issue. Was told by kubota guy that the hydro was going would have to replace it. He didn't pressure test it (which I should have had done, would have saved me money on the item below). Can't afford one new or rebuilt so I bought a used hydro that was fine; saw the tractor run while it was still in the tractor. Thought, I've got this whipped." Wrong, installed it, filled with new fluid and filter, checked strainers which were clean, made sure cooler wasn't blocked and.....still the same, very weak high but low seems to pull okay. Anybody have any ideas where I need to look now. About to pull my hair out on this one. Any suggestions greatly appreciated!

 

[dmanlyr]

Are you sure that you are not expecting too much out of high range? It is not abnormal to not be able to pull steep hills in high range, at least at any speed.

That said, describe what it is doing, is the engine stalling out or is it like the hydro is freewheeling? If it is stalling out, then you are simply running out of horsepower, if it seems to slip or freewheel, then I would agree that the hydro is weak?

One additional thought, is the HST pedal linkage correctly adjusted per the manual?

David

 

[Donystoy]

When I got my new B7200HST almost 30 years ago I drove into a 3' ditch on my first day and could not climb out of it. I am thinking what kind of a tractor is this and called a tow truck to get me out. I had seen these tractors operating at the farm shows etc. and wondered what was wrong. While getting to sleep that night it suddenly came to me. It was in high range! DUH!

 

[Ban One]

I have left the center cover off where I can visually see the hydro and drive shaft. When I try to go up a hill the engine does not lose power and lug down. The drive shaft appears to still be turning the same speed even while not moving. If I gently depress the pedal, it will try to advance, but not move very much, maybe less than a foot and stall, but doesn't have a whine to it. I am basing my experiences with my tractor on the fact that I use a B7100 to do work on the local ball fields and that tractor will climb a lot steeper hill in high range than my tractor will, with no problem. Another thought that might help is with most hydros when you let off the pedal, the tractor will almost instantly stop, but mine eases to a stop in high range, but acts more accordingly in low range. When you release the pedal, it stops almost instantly. Hope this helps.

 

[North Idaho Wolfman]

What brand and type of fluid are you using?
What brand and filter# for the HST?
What brand and filter# for the hydraulic?
Was the pick up screen on the left hand side plugged at all when you pulled it out and cleaned it?
Did you also pull the hydraulic screen on the right side too, if it's plugged the
hydraulic pump can rob from the HST unit.
How does the three point work, strong?
Does it have a FEL on it?

 

[ShaunRH]

There have been other recommendations to lay off the HST pedal and bring it back since you are probably cavitating the hydraulic pump with trying to go wide open up a hill in high.

I don't have an HST so I'm just passing on the concept.

 

[dmanlyr]

Just a random thought - we had a few earlier this year, the tires had lost enough pressure that the rims were spinning in side the tires.

Could this be the issue? That would also explain why the same problem is still there with two different HST's

I mean if the driveshaft is turning, that means the HST is transferring power, something has to move or slip past that point.

David

 

[Ban One]

Wolf man, here is information on your questions:
What brand and type of fluid are you using? Xtreme hydro fluid for UDT's from what the container says.

What brand and filter# for the HST? I assume (yeah I know) you are asking about the filter on top of hydro unit: Kubota HH660-36060

What brand and filter# for the hydraulic? Not sure what you mean here?

Was the pick up screen on the left hand side plugged at all when you pulled it out and cleaned it?clean as a whistle.

Did you also pull the hydraulic screen on the right side too, if it's plugged the
hydraulic pump can rob from the HST unit. Same as other strainer.

How does the three point work, strong? Yes will lift a very heavy 4' blade no problem. Leaks off a bit over time, but know why that happens.

Does it have a FEL on it? No

Also a question about tires spinning on rims, no this is not occurring.

 

[Ban One]

Dman, sorry about not getting back sooner, just had chance today to check the linkage and the adjustment and seems pretty close to the manual, a little wear, but doesn't seem excessive. Looking underneath I don't see any damage or objects that limit the pedal travel either. I've had some great suggestions, hopefully a solution will be in sight soon! Thanks so far everybody.

 

[North Idaho Wolfman]

Sorry some have a second hydraulic filter along with the other HST filter, your does not.

Run the tractor and check the fluid while running. Is it getting foamy?

One odd point that I have discovered, there seams too be 2 different HST filters, and they are 2 compleately different filters not upgrade #'s of an older filter #.
You say you are using a HH660-36060 witch is a replacement # for a 66021-36060 and 66021-36061
Yet when I look up the filter off of the original Kubota specs for your B6100 in parts manuals and from Kubota it calls for a 66204-36160 which updates to a 70000-36160.
it may be just that they discontinued stocking the filter and they now use the other but I still find several vendors stock the 70000-36160.
Might be worth it to get the other filter and give that a try.

 

[Ban One]

I don't think it is foaming, but will look closely later today and verify.

I will give the dealer a call locally and see if they have one. If not will get one online. Boy, that would be great if that is the fix. Do you have any idea what the difference might be? I would think it might have something to do with how much the filter can flow?

 

[Ban One]

Here is some updated information. Fluid does not appear to be foaming. Replaced filter with 36160. Still no change in the way it operates. I thought I had a revolutionary thought; maybe I got the brakes too tight when I had it apart...no such case. But a question to that arises. When you have the range selector in neutral the tractor rolls easily. When I put it in low range it will roll but barely and takes a lot of effort at that. Now, in high range, it isn't as easy to roll as neutral, but can be rolled with minimal effort. Is this normal? This is all without the engine running just to be clear.

Another question is what is the function of the hydraulic pump that is mounted at the rear of the injector pump? I see lines go in and out, but am unsure of its function.