My L3901 seems WAY under-powered to me

[Beeenvenue]

Yeah, that was the stupidest video I have ever seen. He couldn't spin the tires in of the hydro in High range. Yeah, that is real shocking (not). What did he expect.? Then he gets on the gear tractor and puts it in High range, BUT he DOES NOT PUT IT INTO 4TH GEAR.. NO HE PUTS IT IN 1ST GEAR AS IF THAT WAS AND EQUAL TEST. Yest he puts in in HI 4thd finely and give it a jerk, and slips the clutch to keep the engine from stalling, but the test was an idiot test to begin with. Then he goes on to tell you the gear drive "might" have a lower final drive. Of course it does. My guess is he had an excess of gear machines on the lot that day. You may have notice he DID NOT put the hydro machine in MED let alone LO range and test there did he? NOOOOO we are going to do a pulling test in HI range. IDIOTIC. STUPID, DISINGENUOUS, UNCALLED FOR.

Mere words alone could not express my thoughts on this worthless test. Give me a call on the phone and I will tell anyone what I really think.

Worse than that, he mashes the “gas pedal” to the floor. On an hst if you need more power you LIFT your foot to “downshift”. So he used the absolute least power combination possible on the hst machine.

 

[k0ua]

I think most of us agree that the test was unrealistic and invalid from the get go. The posting of the video itself wasn't the thing that that "steamed my clams" it was the person that did it that really torqued me. He should have know better, being a professional in the business.

 

[CH4Ohio]

It's really hard to believe that someone working at a Kubota dealer is so mechanically inept and lacking in basic understanding about the tractor. I pity the poor customers that he's advising. I assume that Messick's management reviews these videos prior to them being published online -- wouldn't you think someone would have caught this nonsense before it went public?

Agree completely with k0ua. High range is not designed for any type of work, and to use it in a PULL test is simply asinine.

 

[ptsg]

Agree completely with k0ua. High range is not designed for any type of work, and to use it in a PULL test is simply asinine.

You do realize that field plowing is often done in High range right? Usually first or second gear. Same for pulling discs. Also pulling trailers on the road, etc.

Of course, this only applies to the Geared tractors as these can actually do something in High range. High range is pretty much useless on an HST.

 

[CH4Ohio]

You do realize that field plowing is often done in High range right? Usually first or second gear. Same for pulling discs. Also pulling trailers on the road, etc.

Of course, this only applies to the Geared tractors as these can actually do something in High range. High range is pretty much useless on an HST.

Right. I'm referring to HST only. High range is not designed for work.

 

[CH4Ohio]

You do realize that field plowing is often done in High range right? Usually first or second gear. Same for pulling discs. Also pulling trailers on the road, etc.

Of course, this only applies to the Geared tractors as these can actually do something in High range. High range is pretty much useless on an HST.

Also worth noting . . . This is a valid point that you make.

Tractors designed for field plowing have their gear ratios and transmissions designed for the most efficient speed while providing the necessary torque and power. That's a very different animal from the L3901 HST in the video. It's not designed to perform that way in HIGH range.

 

[CH4Ohio]

I'm really confused by all the talk about "upshifting" or "downshifting" based on "tram" or "pedal" pressure / position when using HST tractors. I know I'm going to take a lot of fire here, but there's really no such thing.

The typical HST CUT tractors discussed on this board have 3 ranges. Those ranges provide very different performance bands related to the amount of power transferred from the engine to the drivetrain at any given RPM.

Pushing down lightly on the pedal provides the least amount of fluid flow to the HST and the least amount of speed / push / pull -- essentially "power".

Pushing down more, or all the way, provides the most fluid from the pump to the drivetrain and results in the most speed / push / pull -- essentially "power".

Help me understand this talk about "tram" / "pedal" position and "downshifting" please. Thanks.

 

[ptsg]

I'm really confused by all the talk about "upshifting" or "downshifting" based on "tram" pressure / position when using HST tractors. I know I'm going to take a lot of fire here, but there's really no such thing.

The typical HST CUT tractors discussed on this board have 3 ranges. Those ranges provide very different performance bands related to the amount of power transferred from the engine to the drivetrain at any given RPM.

Pushing down lightly on the pedal provides the least amount of fluid flow to the HST and the least amount of speed / push / pull -- essentially "power".

Pushing down more, or all the way, provides the most fluid from the pump to the drivetrain and results in the most speed / push / pull -- essentially "power".

Help me understand this talk about "tram" position and "downshifting" please. Thanks.

The HST are basically a fixed displacement motor with a variable displacement pump. Moving the pump swash plate, changes the displacement of the pump and will make it either pump more flow or less flow.

It takes way more HP to pump let's say 20 GPM at 3000 PSI, than it takes to pump 5 GPM at 3000 PSI. The flow (GPM) gives you the speed. Pressure is given by whatever resistance is being created, in this case, a hill, pulling something, etc.

So when pressing the HST pedal a little bit, you're telling the pump to pump less volume which, again requires less HP. If you press the pedal fully down, you telling the pump to pump all the flow it has, which requires most of the HST and then some.

To make it simpler for people that don't exactly understand how this transmission work, we often mention upshifting and downshifting as in press the pedal more or less. It's easier for them to understand when comparing on the geared transmission.

I hope my explanation is somewhat understandable.

 

[CH4Ohio]

The HST are basically a fixed displacement motor with a variable displacement pump. Moving the pump swash plate, changes the displacement of the pump and will make it either pump more flow or less flow.

It takes way more HP to pump let's say 20 GPM at 3000 PSI, than it takes to pump 5 GPM at 3000 PSI. The flow (GPM) gives you the speed. Pressure is given by whatever resistance is being created, in this case, a hill, pulling something, etc.

So when pressing the HST pedal a little bit, you're telling the pump to pump less volume which, again requires less HP. If you press the pedal fully down, you telling the pump to pump all the flow it has, which requires most of the HST and then some.

To make it simpler for people that don't exactly understand how this transmission work, we often mention upshifting and downshifting as in press the pedal more or less. It's easier for them to understand when comparing on the geared transmission.

I hope my explanation is somewhat understandable.

Thanks. I think you basically explained it the same way that I did.

There are many examples on many forums here where it's suggested that reducing pedal-pressure or pushing down LESS on the HST pedal results in a "downshift" or more available power. That's what I'm referring to. It doesn't work that way.

I suspect that some of the confusion is coming from people trying to WORK these small HST tractors in HIGH range. The result is very weak performance and lot of whining from the transmission. When you're in the proper HST range for your application, and the tractor can handle the load properly, this isn't an issue.

Thanks again.

 

[ptsg]

Thanks. I think you basically explained it the same way that I did.

There are many examples on many forums here where it's suggested that reducing pedal-pressure or pushing down LESS on the HST pedal results in a "downshift" or more available power. That's what I'm referring to. It doesn't work that way.

I suspect that some of the confusion is coming from people trying to WORK these small HST tractors in HIGH range. The result is very weak performance and lot of whining from the transmission. When you're in the proper HST range for your application, and the tractor can handle the load properly, this isn't an issue.

Thanks again.

It kind of works like that.

Think like this then.

On a geared transmission, you have usually 4 main gears and 3 ranges. Forget the range part of the transmission now. You're going on the hill in 4th and it starts to bog down, you downshift to 3rd, or 2nd if need and so on.

On an hydrostat transmission, you're going on the same hill, pedal smashed all the way down and it starts to bog down. You lift the pedal slightly till it stops bogging down. Pretty much like downshifting on the geared transmission.