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Hi all,
I was curious about how the loader speed is affected by RPM so I did a simple test with a timer. Starting at idle with an empty bucket, I raised the loader all the way to the highest position and recorded the time. Then I lowered it back to the ground and repeated. I ran each cycle multiple times until the results stabilized to account for me adapting to using the timer.

Here is what I got. The time is time it takes, in seconds, from the moment I pull back on the stick and the bucket is resting on the ground to the time it reaches its highest position and jerks against the stops.

RPM TIME
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Idle........8.63
1000......8.12
1100......7.37
1200......6.98
1300......6.26
1400......5.77
1500......5.49
1600......5.09
1700......4.75
1800......4.57
1900......4.25
2000......4.10
2100......3.93
2200......3.75
2300......3.65
2400......3.49

Above 2400 it didn't change, so I stopped there.

What I learned from this is that when I am doing loader work, I want to set the throttle to somewhere around 2000 RPM and then use auto-throttle to move around. There doesn't seem to be any point in using more fuel to save a half of second or less.

I plan to make a YouTube video about this, using both an empty bucket and a bucket full of gravel, but I will wait until it's warmer outside and until I have some gravel delivered.

I hope this helps!
 

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You mentioned gravel. I wonder if the speed difference would be more pronounced at higher ROM’s under load such as a bucket full of gravel?
 

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You mentioned gravel. I wonder if the speed difference would be more pronounced at higher ROM’s under load such as a bucket full of gravel?
It shouldn't unless the engine bogs down. The hydraulic pump is constant displacement so flow would stay the same. The only thing that should change is the load, so the pressure increases to compensate.
 

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Good stuff, thank you. I'm going to have to practice using auto throttle with the loader more. I didn't like it at first but I'm still feeling out my machine.
 

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I normally run my 2038R using auto-throttle except if I am mowing, snowblowing, running the backhoe, or doing heavy earthmoving with the loader. Otherwise it’s auto-trottle all the way.

Sincerely
 
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Hi all,
I was curious about how the loader speed is affected by RPM so I did a simple test with a timer. Starting at idle with an empty bucket, I raised the loader all the way to the highest position and recorded the time. Then I lowered it back to the ground and repeated. I ran each cycle multiple times until the results stabilized to account for me adapting to using the timer.

Here is what I got. The time is time it takes, in seconds, from the moment I pull back on the stick and the bucket is resting on the ground to the time it reaches its highest position and jerks against the stops.

RPM TIME
---------------
Idle........8.63
1000......8.12
1100......7.37
1200......6.98
1300......6.26
1400......5.77
1500......5.49
1600......5.09
1700......4.75
1800......4.57
1900......4.25
2000......4.10
2100......3.93
2200......3.75
2300......3.65
2400......3.49

Above 2400 it didn't change, so I stopped there.

What I learned from this is that when I am doing loader work, I want to set the throttle to somewhere around 2000 RPM and then use auto-throttle to move around. There doesn't seem to be any point in using more fuel to save a half of second or less.

I plan to make a YouTube video about this, using both an empty bucket and a bucket full of gravel, but I will wait until it's warmer outside and until I have some gravel delivered.

I hope this helps!

Would it not be common sense the faster the RPM, The quicker the oil pump moves fluid ? The hydro system has a lot of resistance with forcing fluid through tiny hydraulic lines and a small GPM pump capacity. Fluid also creates heat when prompted to move at a fast rate.
I don't believe you can educate anyone on U Tube about the relationship of RPM to movement in oil pump flow. If this was not the case all of us would do out activities at an idle to save fuel and excess wear . How many excavators with three foot buckets have you observed digging at very low engine speed ? 1/4" or 1" lines, the theory is the same for mass movement of fluid.

It all boils down to what engine speed your comfortable with and how fast you want to complete the work. Obviously at low RPM a shovel will compete with your actions.
 

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Discussion Starter #7
Yes it's obvious that the higher the RPM, the higher the flow.

However, what is not obvious is where the sweet spot is. What RPM saves you the most fuel and engine wear while allowing close to optimal loader function? Or even what the minimum RPMs are for the fastest loader function?

Did you know that, before looking at the data above?
 

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Thanks for the info Mike,
I usually feel that 2000 RPM is the sweet spot, but this confirms it.
I have 50 hours on my 2032R and I love it. I don't love the auto-throttle yet, but I haven't messed with it much yet either.
 
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Good info. Thanks for sharing.

Rob
 
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Thanks for the info Mike,
I usually feel that 2000 RPM is the sweet spot, but this confirms it.
I have 50 hours on my 2032R and I love it. I don't love the auto-throttle yet, but I haven't messed with it much yet either.
I think that pretty much holds true for most smaller tractors. It's not the clearest of photos but if you take notice on the Kubota BX tachometer shown below, they show a recommended mid-range RPM for Loader/Backhoe use and then a much higher RPM for PTO use.
 

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Yes it's obvious that the higher the RPM, the higher the flow.

However, what is not obvious is where the sweet spot is. What RPM saves you the most fuel and engine wear while allowing close to optimal loader function? Or even what the minimum RPMs are for the fastest loader function?

Did you know that, before looking at the data above?
I didn't know actual numbers, but as I accumulate hours on my machine it becomes a seat of the pants thing as to where that sweet spot is.
I'm close to 200 hrs now so I know my machine pretty well. Thanks for taking the time to do the research for us though.:thumbup1gif:
 

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Discussion Starter #12
I used to do seat of the pants also, but my seat of the pants told me it was around 2300 RPM. Now I'm going to use 2000, which will save me money.

The loader feels (and is) faster at 2300 RPM than at 2000, but the actual difference is infinitesimal.
 
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I used to do seat of the pants also, but my seat of the pants told me it was around 2300 RPM. Now I'm going to use 2000, which will save me money.

The loader feels (and is) faster at 2300 RPM than at 2000, but the actual difference is infinitesimal.
I'd say 2000rpm is a good # that I favor. I never really need more than that unless doing PTO work. (snowblower-mower deck)
 

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I agree that 2,000 rpm is a good loader number! I don't always use max rpm for the mower deck either. Actually, I play with the rpm's with all my implements!:)
 

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My tractor is up north so I can't check, but there's a economy PTO symbol on the tach. I don't recall the RPM it's at though.
I bet it's close to 2000.
 
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Discussion Starter #16
My tractor is up north so I can't check, but there's a economy PTO symbol on the tach. I don't recall the RPM it's at though.
I bet it's close to 2000.
There are two PTO symbols on the tach. The ePTO one, which doesn't belong on our tractors, is somewhere below 2000 (I think 1900?). This serves a reminder that JD reuses parts and can't be bothered to remove something that doesn't belong because they don't care about us. That is its only function.

The real PTO symbol is somewhere around 2500 RPM, which is where a typical 540 implement will achieve 540 rotations per minute (and a 2000 will achieve 2000 when run off the mid PTO).
 

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I will have to respectfully disagree with you on that. Since my manuals and tractor are up north, I'll have to leave it at that for now.
 

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I will have to respectfully disagree with you on that. Since my manuals and tractor are up north, I'll have to leave it at that for now.
What exactly are you disagreeing with? The positions of the PTO symbols? Here is a pic:

LV25927.jpg

This is accessible online in the owners manual.

As for the ePTO thing, the manual says:

D - Rated Economy PTO Speed - Not used.

You can find all of this here. Look in the Instrument Cluster section.

OMLVU31185
 

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I used to do seat of the pants also, but my seat of the pants told me it was around 2300 RPM. Now I'm going to use 2000, which will save me money.

The loader feels (and is) faster at 2300 RPM than at 2000, but the actual difference is infinitesimal.
Not much, nice study Mike, but on non PTO it would take a lot of hours to see a savings based on 300 rpms.
 

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Not much, nice study Mike, but on non PTO it would take a lot of hours to see a savings based on 300 rpms.
Perhaps, but it will save save some fuel, and some engine wear, and some of my hearing if I'm not wearing plugs.
 
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