Hydraulic Cylinder ends ?

[pokerboy57]

I was thinking about replacing the cylinders on my FEL to try and add some extra lifting capacity. Are the connecting ends of a hydraulic cylinder changeable / customizable ? Seems that this is going to have to be done for the replacement cylinders to fit the FEL ? I was going to go to a commercial hydraulic shop here in Orlando and see what ideas they have. I just wanted to know your opinion before I start down this road ?

 

[LD1]

WhAt are you wanting to do that you need extra lift? IIRC, the 300 loader specs pretty stout given the weight of the machine? Have you had your pressure tested? I would start there if you feel it is weak.

As far as cylinder ends, they can be had in about any configuration. But keep in mind, the loader strength and front axle is designed around the cylinders they use. There is a reason they idint go bigger. And also, a larger cylinder will be slower too.

 

[texasjohn]

What LD said +1

 

[J_J]

Actually, you can do just about anything with a welder, hyd, and well placed thoughts.

2 in cyl 1 in shaft at 2500 psi = 7854 lbs

3 in cyl 1.2 in shaft at 2500 psi = 17,672 lbs

You don't want your cyl to contact the frame except at the ends.

Yes, a larger cyl will increase the force, but may increase your tipping potential. However that can be resolved with rear weight.

Like someone said, check your relive valve specs.

A decrease of 200 psi will cause you to lose about 608 lbs. of lifting weight.

 

[LD1]

If I remember right, assuming he is talking about his 3320, I was thinking the lift capacity was somewheres around 2000# at the pins to a height of 59". Thats an awfully lot for a 2900# tractor to be lifting.

And a 200psi decrease might not quite be 608# of lost capacity. Not sure what bore size cylinder is on the 300 loader. But 608# might be what is lost in cylinder force. But the loader has a mechanical advantage over the cylinder. IIRC when I figured out the geometry of my similar sized loader, each psi was equal to roughly a pound of lift for the total system. My loader has 1.77" bore cylinders.


Not that I frequent the deere section much, but I dont recall any threads about a 3320 having a weak loader??

 

[J_J]

There is no mechanical advantage in the lifting cyl.

If you had a cyl pushing perpendicular to the cyl base line, 90 degrees, then you have max force.

Using the 2in bore and 1 in shaft at 2500 psi, at 90 degrees = 7,854 lbs.

Any angle less than 90 is a decrease in force. Using an angle of 45 degrees, you would have a force of 5,556 lbs.

An angle of 30 degrees = 3,927 lbs

The higher you lift, the less force you can lift, based on the geometry of the lift arms.

As many people have experienced, you might be able to lift a certain distance, and then it quits, where you are at your limits based on the angle and the pressure. Sometimes you can tilt the load back over the lift pins and gain some force.

 

[LD1]

I am refering to the mechanical advantage of the loader over the lifting cylinder.

A 200 PSI loss may cause a 608# decrease in force in each of the cylinders. But in a typical loader, that isnt 608# of lifting force lost.

If his tractor makes 2500psi, and has a loader rated to lift 2000 lbs, it may take ~500psi just to lift the dead weight of the loader. Leaving 2000psi to lift 2000#. Roughly 1psi = 1# of lifting force.

I think you are talking about strictly cylinder force. Whereas I am talking about the rating of the loader at the bucket pins.

Since his loader is rated ~2000lbs lift to 59", loosing 200psi on a 2500psi system (8%) wouldnt cause him to loose 30% of his rated capacity.

 

[Kernopelli]

LD1... I think you are making an argument for exactly what JJ explained. Yes, in the first examples JJ gave, the cylinder itself loses a total force of 608# with -200PSI. In JJ's original statement there is no "mechanical advantage" to the cylinder itself other than and increase or decrease in PSI x area, either one equals a finite number....period. He never said exactly what the FEL would lose at -200PSI, that PSI/force figure was clearly related to the cylinder only. He went on to say. " Yes, a larger cyl will increase the force" ( of the cylinder and obviously to the loader as he explained how it could effect the tractor)..... he never said EXACTLY how much the Deere's FEL lift changed, only a larger cylinder at the implied same PSI increased force. It seemed clear/ easy to understand to me. You are saying the geometry of the loader effects the actual capacity of the FEL, which is correct... exactly what JJ explained. I think you are both explaining the same thing using different wording.

To the original question the OP had: Yes, cylinder ends can be changed. If the rod end is threaded a new threaded end can be screwed on. Otherwise, a welder and means to cut the ends is all that is needed. Last week, I changed my backhoe's factor 3" cylinder with swivel ball ends to an aftermarket 3.5" cylinder that came with DOM tube ends. I cut the ball ends off the OEM cylinder and cut the tube ends off the factory cylinder. I then welded the ball ends to the new, larger cylinder. Worked great!!

Here is a TBN link to a similar Deere FEL cylinder update http://www.tractorbynet.com/forums/build-yourself/186398-upgrading-john-deere-loader-cylinders.html. He has great youtube links to the entire project.

 

[LD1]

A decrease of 200 psi will cause you to lose about 608 lbs. of lifting weight.

When he said this, rather he meant it or not, I took it to mean what the loader could lift.

Now I know I aint very good at explaining things all the time. But was just trying to clarify that what he said is NOT what the loader would loose in lifting ability. Rather, that number is roughly what a 2" cylinder would loose in push force by being 200psi low. And that if the loader is indeed equipped with 2" cylinders, the actual loss of lift at the bucket would be roughly 1 pound per 1 psi.

 

[J_J]

Those figures I posted were for one cyl, so with two cyl you actually have more of a loss.

The cyl bore size and shaft size were hypothetical as I don't know the exact size.

There is always a disadvantage in lifting force unless you are lifting perpendicular to the lift arms.

What comes after that is the fulcrum effect where the further you go past the lifting point you lose lifting potential.

The only time you would ever have a mechanical advantage is if you were to lift something between the fulcrum point and the lifting point, and tractors loaders don't do that.

Then you have the length of the bucket lip which is out past the pin lifting point.

 

[pokerboy57]

Folks,
Thank you everyone for your very helpful advice. I would have responded sooner but work got in the way. For those of you interested the 300 loader wasn't sold on the 3320. These are the joys of purchasing a used tractor without much experience. The 300 loader is rated at 800 ilbs at the pins so not a lot of lifting capacity after you add an attachment. The diameter of the lift cylinders is 1 and 1/2 incjes and the "bore" I assume it's called is 1 inch in diameter. So I'm going to go down to my local hydraulics shop and sacrifice lift speed and maximum height for "hopefully" and extra 50% lift capacity. That's my goal .... then I can justify a small grapple. BTW: A new CX300 loader is around $6000 dollars. I found a used one in MN for $2800 but that's a little far for me to drive and pick it up. If I do go through with this customization I'll let you all know how it turns out. The good, the bad and the ugly.

Ray

 

[J_J]

You might look here and see if there is anything that will work for you.

Surplus Center

http://www.ehow.com/info_8726509_difference-between-300x-300cx-loader.html

 

[LD1]

Now I am confused. What loader do you have?

You said the 300 loader wasnt sold on the 3320, then you said the 300 loader has 800# lift at the pins

So what exact loader do you have?

A loader rated at 800# is one that would be found on a scut. And certainly not a 3320 deere.

 

[J_J]

Excerpt:

The 300CX loader can be used with John Deere compact tractor models 3320, 3520, 3720, 4005 and 4105. When used with these tractor models, the lift capacity of the 300CX loader ranges from 2,200 lbs. to 2,500 lbs.

Is it a plain 300 loader? Here are the specs used on a different tractor.

http://www.deere.com/wps/dcom/en_US...oading_and_digging/300_loader/300_loader.page

Lift capacity at full height, lb (kg)
---
Measured at pivot (U)
741 lb
336 kg
Measured at 500 mm ahead of pivot (V)
547 lb
248 kg
Measured at 800 mm ahead of pivot (V)
---
Lift capacity at 59 in. (1500 mm), lb (kg)
---
Measured at pivot (W)
961 lb
436 kg
Measured at 500 mm ahead of pivot (X)
741 lb
336 kg
Measured at 800 mm ahead of pivot (X)
---
Boom breakout force, lbf (kgf)
---
Measured at pivot (Y)
1729 lb
784 kg
Measured at 500 mm ahead of pivot (Z)
1230 lb
558 kg
Measured at 800 mm ahead of pivot (Z)
---
Bucket rollback force capacity, lbf (kgf)
---
At maximum height (VV)
1160 lbf
526 kgf
At 59-in. (1500-mm) lift height (XX)
1450 lbf
658 kgf
At ground-level line (ZZ)
1115 lbf
506 kgf
Dimensions
---

 

[LD1]

Wow, I didnt think the plain 300 loader was that bad. And I also didnt think it was offered on the 3320.

Which would have either the 300x or 300cx. When I was refering to 300 loader, was really meaning 300 series as I dont know weather his is the X or CX.

 

[J_J]

What would change the lift capacity on a loader from tractor to tractor since the power to lift comes from the hyd pressure. The pivot point is still the same.

I can see the tipping part, but the right ballast on the rear should take care of that.

Size of bucket might have some effect, very small.

If the front axle and wheel assembly were weak, then I could see the lower safty figure also.

About the only thing I can see is maybe the pressure is different on certain tractors, giving advantage to the higher psi models.

 

[pokerboy57]

I purchased the tractor used....... At the time I wouldn't have known a 300 loader from a Baldwin piano...... It's definitely a 3320 tractor which is a fine machine. And it's definitely a 300 loader. It was 4 years ago when I purchased this unit. It took me some time to figure out that something wasn't right. A new CX300 loader is not cheap. I think starting with carefully measuring the hydraulic pressure is an excellent low cost place to start.

 

[LD1]

Do you have any pictures? How are you positive that it is a 300 loader and not a 300x?

Pressure is a great place to start.

And in an earlier post, when you mentioned that you thought the cylinder bore was 1", how did you come to that conclusion? It is hard to put a finger on the bore size of a cylinder without actually taking it apart. And also just wanting to be sure that you were not measuring the rod itself...

 

[pokerboy57]

I've upladed several photos. One will give you an idea of what the land looks like prior ro clearing it with the tractor. The second shows the model numbr on the loader. The third shows the piiston part of the cylinder that measures 1 inch,.

So how would I go about measuring the hydraulic pressure ?

 

[LD1]

That ain't the piston. That's the rod. And I have no idea for sure what loader it is. But if indeed it is a 300 and not a 300x, it is too small and underpowered for a 3320. But don't know if it can handle larger cylinders that develop more force, from a structural point