
L4330 Really Sluggish
![]() | retcol
Join Date: Sep 2004 Posts: 109 Barron,wi ![]() |
2010-08-17 173197
I have a L4330 HSTC that is really sluggish on the road. Yesterday I was pulling a small baler. On the hills that weren't that steep the tractor would lose about 1000 rpm. Is this normal? I have some collector tractors with about the same rated horsepower but they aren't that sluggish
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L4330 Really Sluggish
![]() | Murf
Join Date: Dec 1999 Posts: 7248 Toronto Area, Ontario, Canada ![]() ![]() |
2010-08-17 173204
What range were you in, high?
I pull all kinds of stuff with my L4310 HSTC, no problems.
Best of luck. ....
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L4330 Really Sluggish
![]() | kthompson
Join Date: Oct 2005 Posts: 5275 South Carolina ![]() ![]() |
2010-08-17 173206
If you have 4 wheel drive are you running in 4 wheel drive on firm road surface? If so the drive train is/will bind some.
Next question what RPM are you running? The HST needs full or near it RPMS. ....
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L4330 Really Sluggish
![]() | retcol
Join Date: Sep 2004 Posts: 109 Barron,wi ![]() |
2010-08-17 173209
High range. ....
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L4330 Really Sluggish
![]() | retcol
Join Date: Sep 2004 Posts: 109 Barron,wi ![]() |
2010-08-17 173210
The tractor is not in 4WD. I run it wide open which is around 3000 rpm. ....
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L4330 Really Sluggish
![]() | kthompson
Join Date: Oct 2005 Posts: 5275 South Carolina ![]() ![]() |
2010-08-17 173212
On your collector tractors assume they are gear transmission, in the same HP range would they run the same climb in high gear or would you need to drop a gear or so? If so think you need to back off on the foot pedal if not drop the Kubota a range also. My opinion and might have many to disagree with me those old farm tractors just had better torque then the smaller same hp engines. ....
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L4330 Really Sluggish
![]() | hardwood
Join Date: Dec 2002 Posts: 3583 iowa ![]() |
2010-08-17 173215
KT;
You are correct, the old Farmall "M" for example had a high idle of I think around 14-1600 RPM. You could lug one down to 1000-1200 and they would hang in there till the load became lighter then she'd pick back up and you didn't hurt the "M" unless you lugged it that hard from sunrise to sunset. Those old engines had lots heavier insides, crankshafts, flywheels, etc. that resulted in lots more low end torque. Todays tiny high RPM diesels wouldn't weigh a third as much as the engine from an "M" but will produce the same power so as long as you keep the RPM's up. They are proven to be good little engines but they just aren't meant to be lugged, no matter the brand.
Frank. ....
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L4330 Really Sluggish
![]() | Murf
Join Date: Dec 1999 Posts: 7248 Toronto Area, Ontario, Canada ![]() ![]() |
2010-08-18 173245
I suspect what you're running into is what my lead hand jokingly refers to as "gear foot" on the new employees.
A hydro-drive is not at all the same as a gear drive unit, and must be driven quite differently also or some damage to the drive train will occur (eventually).
First of all, forgive me if you already know, but a very brief lesson on how the HST works. The engine is connected directly to a 'swash-plate' style of pump. The pump in turn drives a hydraulic motor that is driving a 3 speed gear transmission.
The pump is different in that it is infinitely variable in it's displacement. The pump can make (like any pump) high volume at low pressure, or high pressure at low volume, and anywhere in between. This is what gives you the ability to have 100% power at a bare creep all the way up to roading speed in a single 'range' (gear actually).
The problem is, when the pump is running at high volume, low pressure, it lacks the ability to deliver high torque because the pressure needed to do that has been sacrificed to volume.
So, back to your problem, yes, what you are experiencing is 'normal' for a hydro-drive unit, they all do it.
The bottom line is you need to ease up on the pedal to maintain very close to full revs. You will lose speed, but unless it's a really big hill, you shouldn't lose as much speed as lugging it would cost you.
Again, lugging a hydraulic drive like that, is very hard on them, you should avoid it all cost.
Best of luck. ....
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L4330 Really Sluggish
![]() | charlieK
Join Date: Feb 2004 Posts: 136 kentucky ![]() |
2010-08-22 173354
never lug a diesel--no matter what trans ....
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L4330 Really Sluggish
![]() | Murf
Join Date: Dec 1999 Posts: 7248 Toronto Area, Ontario, Canada ![]() ![]() |
2010-08-23 173374
It's pretty tough to 'lug' a diesel connected to a HST type transmission, in fact I'd say it's darned near impossible. Just as in this case, the trans. runs out of grunt long before you pull the engine down and the operator gives up a lets back off the control.
According to Cummins, they define "lugging" about the best I've ever seen, that is when you have the engine under sufficient load that it's RPM drops below the point of peak torque (usually about 1,600 in a 'modern' diesel) and increased throttle will not bring bring the revs back up above the peak torque point. They say that 'lugging' an engine like that is harmful after as little as 30 seconds.
They also say that 'loading' an engine up to that point is not harmful at all, that is merely doing the work it was designed to do.
Best of luck. ....
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