Flow/PSI Chart Hydrostatic subcompact FEL

[HangarDebris]

I hope I don't get yelled at but I couldn't find any really right on questions/answers for this item.
Q. Am I reading this chart right? maximum flow is 6.25 GPM@340 PSI can this be real?

This is the chart from my manual and I am trying to trouble shoot the fact that my FEL will not perform but to half its rated performance.
My FEL is a Koyker model 80 and at 2500 psi should lift to maximum height at like 3 seconds at 960 lb. or 700 lb. 20 inches ahead of formost pivot.

My tractor is a Simplicity Legacy XL 27 HP 4X4

It features a built in valve and may be simular to a like Cub Cadet. It is a good work horse for what I do (which is nothing really) but would really like it to lift at least 700 lb. at the front pivot.

Q. Is it likely I would find and adjustment to regulate this ability? The manual does not seem to address this issue.

Valve location:

Thanks,

Jim
PS Looking for 20 long acres between Kimberly ID and Cadwell ID with a modest house on it (so I can use my tractor.

 

[HangarDebris]

Acually the valve itself is conncet to this lever by rods and is located lower in the tractor.

 

[HangarDebris]

Sorry, here is a picture of the valve, still checking the manual.

 

[3RRL]

That is a cool little tractor you got. I take it then that the chart is from your tractor, right. Since I don't know anything about your tractor, does that mean your tractor's hydraulics put out 6-1/4 gals/min and 340 psi? That's what I see. If that's the case, your loader is rated at 2500psi and you're a little short.

Maybe you can call the dealer and verify the tractor's hydraulic out put.

 

[crashz]

Well your chart shows the flow vs pressure. At 0 pressure, you hydraulic pump produces the most flow 6.25 gpm. Under load the pump will put out less flow, like 5.25 gpm at your max pressure of 340 psi.

The flow isn't the problem, its your max hydraulic pressure. If the loader is rated for 2500 psi, your hydraulic cylinders have much less force than they are designed for. This is why you can't lift very much.

 

[JerryG]

Good morning Jim,
Great job you did with your tractor.
A question or two to try to help.
I take it that this valve was originally on the tractor?
What is the hydraulic system used for other than the loader?
Are their any type of aux. outlets?
What is you sump capacity?

 

[HangarDebris]

JerryG Good morning Jim,

Good Morning,

Great job you did with your tractor.

Thank you.

A question or two to try to help.
I take it that this valve was originally on the tractor?

Yes, it is the original

What is the hydraulic system used for other than the loader?

The 3 point cat 1 which uses a solenoid to switch between the rear and the front.


Are their any type of aux. outlets?

No other aux out puts. I will grab a schematic from the manual and follow this post. with it.

What is you sump capacity?

The Hydrostatic transmission is also the sump as when I add Type F fluid it goes into the transmission.

Thanks for your help. I am sure there is a simple solution. I can certainly sacrifice flow for pressure if its adjustable.

Jim

 

[HangarDebris]

 

[SkunkWerX]

That chart is really bothering me. First thing to verify is your pump output pressure. As 3RRL stated, if you Max Out at 340 psi, you are a little short on oooomph factor.

But, on the other hand, if this unit from Koyker is intended for your tractor, they certainly wouldn't have lead you to believe you could lift 960 lbs.

The Chart reads "Implement Flow" , I am wondering what they mean by that?

 

[Farmerford]

Jim:

Since your tractor has a hydrostatic transmission I suspect the hydraulics are powered from the "charge pump", which is the auxiliary pump needed in every hydrostatic transmission to keep the hydraulic circuit between the drive pump and the driven motor filled with fluid. Charge pumps in smaller transmissions like those in compact tractors typically provide 200 to 400 psi since that is all that is needed to pump fluid into the low pressure side of the hydrostatic transmission. There is probably a control valve at the charge pump outlet to maintain the required 200+ psi in the transmission circuit, and the fluid from the charge pump that is not required for the transmission is then available for the power steering, three point hitch, and loader.

If I am correct, there is no practical way to increase the hydraulic pressure to the loader since the charge pump is designed as a low pressure pump. You could increase loader capacity by replacing the hydraulic cylinders with larger ones (doubling the diameter quadruples the extend force) or by powering the loader with a 12 volt hydraulic power pack such as those used on dump trailers. In either case the cost will be substantial ($500?) and the loader will move much slower than it does now.

Perhaps your dealer's service department can tell you the test pressures for the charge pump circuit. If they tell you it is in the 300-400 psi range, then it is likely that the charge pump is being used for the auxiliary hydraulics.