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If one was to buy a hydraulic attachment for their 1025r, what size hose/fitting would one need? Length doesn't matter. Would hook it up to the power beyond.
 

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If one was to buy a hydraulic attachment for their 1025r, what size hose/fitting would one need? Length doesn't matter. Would hook it up to the power beyond.
For the PB connections you’d need 3/8” hose and ISO 5675 “AG” style couplers.
 

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If one was to buy a hydraulic attachment for their 1025r, what size hose/fitting would one need? Length doesn't matter. Would hook it up to the power beyond.
The PB on a 1025R will have a flow of about 1.75 gpm, 1/2 of the pump output which is 3.5 gpm. You can use this interactive nomogram to determine the minimum ID for pressure and return lines in hydraulics.

Interactive Nomogram for Sizing Hydraulic Hoses

Keep in mind, the steel line that runs from the PB port of the main SCV to the rear PB QC is 1/4" OD steel tubing. 1/4" I.D. hose will do the job. 3/8" I.D. will easily do the job.
By the way, length of the hose does matter! The longer the hose is, the more resistance to flow there will be and hydraulic hose expands under pressure, therefore, the internal volume of a hose increases as the pressure builds. The hose's volume fluctuation decreases the hydraulic system reaction time and efficiency. This is why hydraulic systems are designed with steel tubing where possible and hydraulic hose where flexibility is needed.

Now for most applications, this lack in efficiency and reaction time isn't super noticeable, so running hose isn't a huge problem.

The nomogram is based on this formula:
 

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The PB on a 1025R will have a flow of about 1.75 gpm, 1/2 of the pump output which is 3.5 gpm.
Can you please explain this better Ray?

According t the posted specs, the 1025R has a 6.3 GPM pump, with 2.8 GPM dedicated to the steering, thus leaving 3.5 GPM for the implements. How do you figure only half of that flow is going to the PB circuit?
 

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Can you please explain this better Ray?

According t the posted specs, the 1025R has a 6.3 GPM pump, with 2.8 GPM dedicated to the steering, thus leaving 3.5 GPM for the implements. How do you figure only half of that flow is going to the PB circuit?
The 1025R doesn’t have a 6.5 gpm pump. It has a 3.5 gpm pump (8 cc displacement). I do not have the time right now to show the math to figure the gpm but it is 3.5 gpm, not sure where you heard it was 6.5 gpm.
That said, 50% of the flow feeds the steering and propel circuits and 50% feeds the main SCV which directly feeds the PB. So, the main SCV, PB and rockshaft Lift sees 1.75 gpm.


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The 1025R doesn’t have a 6.5 gpm pump. It has a 3.5 gpm pump (8 cc displacement). I do not have the time right now to show the math to figure the gpm but it is 3.5 gpm, not sure where you heard it was 6.5 gpm.
That said, 50% of the flow feeds the steering and propel circuits and 50% feeds the main SCV which directly feeds the PB. So, the main SCV, PB and rockshaft Lift sees 1.75 gpm.
Ray,
I'll make this a new thread since we are taking it off of the OP's topic.


I am getting this info from the John Deere web page and the tech manual for the 1025R.

At this link: https://www.ag-power.com/new-products/john-deere/john-deere-tractors-1000-9000-series/tractor-series-1000/john-deere-1025r-24-hp-sub-compact-utility-tractor-detail
HYDRAULICS


  • Type Open Center
  • Pump Rated Output, gpm (L/min.) 6.3 (24)
  • Steering 2.8 (10.8)
  • Implement 3.5 (13.2)
  • Pump Type Gear
  • Maximum Operating Pressure (PSI) 2000
  • Draft Control Type Select Control
  • Remote Control Valves Available 2
At this link: https://www.deere.com/en/tractors/utility-tractors/1-family-sub-compact-utility-tractors/1025r-sub-compact-utility-tractor/
Pump rated outputSteering
10.8 L/min
2.8 gpmImplement
13.2 L/min
3.5 gpm
24 L/min
6.3 gpm

And from the TSM, the expected flow rate at the SCV is 3.5 GPM, not 1.75 GPM:




Also from the TSM, it shows the displacement of the pump at 8 cm/3 per revolution, but we do not know how fast the pump spins so that is meaningless.

 

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OK.. I have a little time to go through the details on this.

I do know the technical manual says you will see 3.5 gpm at the SCV. When I read that in the manual initially, when i first got my 1025R back in late 2013, I thought, based on the 8 cc displacement of the pump, that sounds like the full flow of that sized pump rather than the flow at the SCV. So, I did the math and applied by experience knowledge of component sizing on the system and found this.

To find GPM, the formula is: GPM = (Pump RPM x Pump displacement in cu. in.) / 231

I'll use 2000 pump RPM and 0.48819 cu. in. pump displacement (8 cc - 0.48819 cu. in.)

So..... GPM = (2000 x 0.48819) / 231

GPM = 976.38 / 231

GPM = 4.2

At 1800 pump RPM, the flow rate will be 3.8 GPM. This is why I said the pump output is about 3.5 gpm. In any hydraulic circuit, the pump output will rarely be seen at the function valve simply because of internal hose/line resistance and elbows.

The 1 series has a 50% flow divider that directs 50% of the flow to the steering and propel circuit and 50% to the SCV, PB and rockshaft circuit. Essentially these are two separate loops off the flow divider.

So, if you check the flow at the SCV with the throttle wide open, you may see slightly higher than 2 gpm. If you check at PTO RPM, you will see about 2.0 or more likely, slightly less than 2 gpm.

The other indicator of what the maximum flow is on the 1 series is the OEM installed steel tubing size. All of the steel tubing from the main SCV to the PB is 1/4" OD tubing with a .035 wall thickness. This means the ID of the tubing is .180. The maximum allowable flow rating of .180 ID steel tubing is 2.0 gpm.
 

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The other indicator of what the maximum flow is on the 1 series is the OEM installed steel tubing size. All of the steel tubing from the main SCV to the PB is 1/4" OD tubing with a .035 wall thickness. This means the ID of the tubing is .180. The maximum allowable flow rating of .180 ID steel tubing is 2.0 gpm.
So basically the listed hydraulic flow rates for most JD SCUT/CUT machines are incorrect? That would make it very difficult to purchase an implement that requires a specific flow rate and know that it will work properly.

:munch:
 

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We will have to agree to disagree Ray, as I don't believe you are correct. JD would not expect you to see 3.5 GPM at the SCV if all you wrote is true, that means EVERY 1-series would fail that test, so how would JD handle that? Every owner under warranty could go to the dealer and complain about the hydraulics being slow LOL.

Also we don't know how fast the pump spins, so your just speculating on those numbers.

Great discussion though :bigthumb:
 

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So basically the listed hydraulic flow rates for most JD SCUT/CUT machines are incorrect? That would make it very difficult to purchase an implement that requires a specific flow rate and know that it will work properly.

:munch:
:munch:
 

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We will have to agree to disagree Ray, as I don't believe you are correct. JD would not expect you to see 3.5 GPM at the SCV if all you wrote is true, that means EVERY 1-series would fail that test, so how would JD handle that? Every owner under warranty could go to the dealer and complain about the hydraulics being slow LOL.

Also we don't know how fast the pump spins, so your just speculating on those numbers.

Great discussion though :bigthumb:
:munch::munch:
 

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We will have to agree to disagree Ray, as I don't believe you are correct. JD would not expect you to see 3.5 GPM at the SCV if all you wrote is true, that means EVERY 1-series would fail that test, so how would JD handle that? Every owner under warranty could go to the dealer and complain about the hydraulics being slow LOL.

Also we don't know how fast the pump spins, so your just speculating on those numbers.

Great discussion though :bigthumb:
Agreed!! Good discussion and do understand what you are saying. Thanks!!!


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