My L3901 seems WAY under-powered to me

[crazyal]

I think a little more testing should be done. For example do you have something like a large tree? I would set the RPM to something like 2000 (or higher) and try to push the tree (not ram it) and pay attention to how far you move the pedal. Do it in both low and medium. What does the engine do? Does it spin the tires in low or look like it's close? This is a test that can be performed by others with a similar size tractor. Trying to start off on a hill is much more subjective and hard to duplicate.

My Kubota will bog down some if I try to go up a hill too fast in M. If yours isn't than it does sound like it could be a problem.

As for old farmers and what they would think, I don't get that. A comparable model would be a Ford 8N. Are you saying that a farmer who was using an 8N to farm would think a 3901 couldn't do the same tasks?

 

[kallnojoy]

My tires are filled and I keep the tractor in 4wd all the time along with a tiller on the back for counterweight. It does NOT want to spin the wheels in low, never mind mid-range. I've had a few times digging soft dirt (wash near my creek) and it didn't want to spin the tires at all in low. Since the tractor is fairly new (less that 100 hours) and I generally don't want to abuse my machines by creating cavitation in the hydraulic pump, I backed off and took a lighter bite. Again, this is low-range. Maybe I'm just too gentle and need to lay the whip to it. However, I KNOW it will not spin in mid-range. In fact, I rarely use mid-range because it's seems so under powered that I don't want to cavitate the pump.

Just in case someone is wondering, I know how to use a hydrostatic powered machine. When under load, only apply the tram necessary to get moving, not pedal to the metal. Yes, it's a touchy-feely thing...not enough tram and you don't move, too much and ether the engine (should) start to stall or you push the reliefs into by-pass. But this tractor has no sweet spot. I stopped the other day on a mild slope in mid-range. As I engaged the tram, it did nothing but whine. The engine did not idle down at all. I had to shift into low.

Friend - I work the heck out of mine, without apology. She's 10 years old and only ever asks for more. I've even had 6" spacers on her rear loaded R1s for the last year and she's not even blown a bearing or seal yet. I just came in from several hours of intense grappling, often at max lift capacity (1k+) and driving 1/4 mile each load over bumpy fields and hills. Your L3800 shouldn't disappoint. And yeah, it should spin tires easily enough even in mid. You are working it with sufficient RPMs, yes?

 

[Fallon]

Easy way to demonstrate this effect on an HST tractor is to get moving in any gear and while rolling along, lift the front loader up. You'll notice the tractor slow down and work a little harder. Since the HST is sharing hydraulic pressure and flow with everything else, using the loader or 3-pt takes away from the HST.

This is not how a HST works at all. The HST pump & motor are completely separate from the rest of the hydraulics. There is a fixed displacement gear pump(s) that run power steering, 3pt, loader & any other auxiliary hydraulics. The HST has its own variable displacement pump directly coupled to a fixed displacement motor. On Kubotas at least, probably most machines, the HST also has its own filters for the HST separate from the aux hydraulic filters & circuit.

Any slowing of the machine is due to the engine slowing down due to the extra load from the aux hydraulic pump going from 0 load to some load.

 

[SDT]

Bingo.

SDT

 

[RickB]

Sounds more to me like an engine power issue than a transmission fault. If it has sat for an extended period of time maybe the fuel filter and/or water separator are plugged with algae or water from condensation. The air filter housing may have been stuffed full of debris by rodents.
Let's look at basic service items before condemning the machine, it's size or transmission type.

 

[marrt]

To answer some comments:

I have R4 tires and run the machine at 2800 RPM's (max power) most of the time.

Four filled tires plus a heavy tiller and a bucket does add a lot of weight and may be impacting my experience. I'm pretty sure the tractor would spin everything with unfilled tires and no attachments. But that's mainly due to weight. However, I'm more "concerned" about the engine not bogging when the tires aren't spinning. In other words, if I have too much traction, I would expect the engine to change its tune in protest.

I will try the immovable object test but will need a day to two before I can try it (rain is coming).

Here's a video I discovered last night from our friends at Messick's that I found SHOCKING. Heck, even the employee was shocked. I always knew hydrostatic transmissions were inefficient to a degree. But that's the tradeoff for the improved utility. But still, this video amazed me.

And finally, I'm not dissing the tractor. I have two other Kubota products (RTV and Mower) and my dealer is only 7 miles from my house. If this tractor isn't satisfying, I'll get it fixed or upgrade. It's always nice to have an excuse to upgrade...as I'm sure some of you will agree.

 

[k0ua]

To answer some comments:

I have R4 tires and run the machine at 2800 RPM's (max power) most of the time.

Four filled tires plus a heavy tiller and a bucket does add a lot of weight and may be impacting my experience. I'm pretty sure the tractor would spin everything with unfilled tires and no attachments. But that's mainly due to weight. However, I'm more "concerned" about the engine not bogging when the tires aren't spinning. In other words, if I have too much traction, I would expect the engine to change its tune in protest.

I will try the immovable object test but will need a day to two before I can try it (rain is coming).

Here's a video I discovered last night from our friends at Messick's that I found SHOCKING. Heck, even the employee was shocked. I always knew hydrostatic transmissions were inefficient to a degree. But that's the tradeoff for the improved utility. But still, this video amazed me.

And finally, I'm not dissing the tractor. I have two other Kubota products (RTV and Mower) and my dealer is only 7 miles from my house. If this tractor isn't satisfying, I'll get it fixed or upgrade. It's always nice to have an excuse to upgrade...as I'm sure some of you will agree.

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.

 

[marrt]

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.

I totally get what you are saying, with a little caveat...stick with me. A hydrostatic tractor has the "equivalent" of first gear. That occurs when you're applying just a little tram. Under that condition, the pistons in the variable displacement pump move just a small amount of hydraulic oil on each turn around the swash plate. So, this generates a lot of power.

On the geared tractor, first gear in high range is just past the midpoint of its total range (4 in low and 4 in high I assume). But light tram in high range on the hydrostatic tractor is at the 2/3's point of its range...i.e., a higher equivalent gear ratio. So, I agree...the 1st gear in high range shows nothing.

With the gear tractor in 4th gear high range, it's at the maximum range point. So, in theory, this should be a higher range than the hydrostatic tractor in low tram but high range. In other words, I would have expected the hydrostatic tractor to deliver a little more power at low tram, high range than the gear tractor at 4th gear, high range. Said another way, I would have thought the hydrostatic tractor could have delivered more torque at some point in the tram, even in high range, than the geared tractor in 4th gear high range. Instead, the geared tractor delivered 50% more power.

To get anything useful from this test when looking at the overall capability of both tractors, he would need to try all combinations and use the highest consistent reading. It wouldn't have been that much more work since the highest reading from both tractors would occur just before the tires break loose. In that context, I'd bet the readings would have been similar...i.e., the hydrostatic tractor in low range could deliver the same power.

What we need is maximum drawbar horsepower...which, it seems, not many manufacturers want to list any more.

 

[SDT]

Bingo.

Kubota does not send its tractors to NE for testing, nor do many others these days.

The NE tests remain the gold standard of tractor performance tests but testing is expensive and time consuming.

Of course we all know that gear driven tractors put considerably more HP to the drawbar than do equivalent tractors with HST transmissions. Such is the cost of convenience.

SDT

 

[4570Man]

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.

Putting gear ratio differences aside the test was completely invalid the moment he jerked the chain. If you want a fair test of power to the wheels hook 2 equal trailers on the tractors and race them uphill. If you were going to use the scale he should’ve put a tire in between 2 chains as a shock absorber. Even then a peak reading isn’t very useful. Having someone watch the scale would be better.