John Deere 2040 with Open Center valve on FEL

[Tx Jim]

For me....closed center is easy. Being able to simply tee everything....

You either have oil pressure or you don't. Sure there are wildcard cases like this where one uses a wrong valve.

But in open center stuff.....I thing there is a very very small percent of people that truly understand PB and how it functions.

I think everyone's natural instinct is to plumb as if it was CC (or like they would shop air). Just tap a pressure like somewhere and install valve. Hard to get people to understand and grasp the concept of PB

I agree except diagnosing JD closed hyd system with an internal high pressure leak &/or internal low pressure leak where trans pump supplies oil for trans/pto clutches & then supplies oil to front hyd pump can be a little tedious(have greying/balding affect on technicians hair)

When was power beyond introduced? I don't remember it being in existence when I was employed by dealer but granted I was more focused on CC hyd than OC.

 

[LD1]

I agree except diagnosing JD closed hyd system with an internal high pressure leak &/or internal low pressure leak where trans pump supplies oil for trans/pto clutches & then supplies oil to front hyd pump can be a little tedious(have greying/balding affect on technicians hair)

When was power beyond introduced? I don't remember it being in existence when I was employed by dealer but granted I was more focused on CC hyd than OC.

Not really sure. My hydraulic experience is limited to only a couple of decades. And not much on tractors other than the ones I have owned.

80% of my hydraulic experience is in an industrial setting. With both open center fixed displacement pumps as well as closed center systems with variable displacement pumps and swash plates. Kinda like an AC compressor in your car.

But most industrial systems and valves have fully rated tank ports. Similar to tractors and the electronic 3rd function valves.

And even on those that aren't full pressure rated..."power beyond" which is commonly referred to as "high pressure carry over" or hpco is integral to the base blasted and sub assemblies and manifold blocks on an industrial system. So the average technician is clueless and the lingo is rarely used unless you study schematics

 

[npalen]

That's interesting! Any online animations showing how this works?

Starting just before the 2:00 minute on the timeline shows the cam operated pump. This is new to me and a very interesting video.

 

[Tx Jim]

For me....closed center is easy. Being able to simply tee everything....

You either have oil pressure or you don't. Sure there are wildcard cases like this where one uses a wrong valve.

Have you ever diagnosed a malfunctioning JD CC hyd system?

 

[LouNY]

And now throw in the "new" (since the 80's) larger tractors with pressure compensated closed center or as it may be called closed center pressure flow compensated (PFC). With a sense line on every valve that run back to the pump control.
Talk about making a balding old man pull out more hair.
If the sense line screws up the pump will not kick in the higher pressure flow mode, and you will only get a few hundred psi and a few gallons per minute.

 

[Tx Jim]

Starting just before the 2:00 minute on the timeline shows the cam operated pump. This is new to me and a very interesting video.

I wonder what year that video was made?

 

[Tx Jim]

And now throw in the "new" (since the 80's) larger tractors with pressure compensated closed center or as it may be called closed center pressure flow compensated (PFC). With a sense line on every valve that run back to the pump control.
Talk about making a balding old man pull out more hair.
If the sense line screws up the pump will not kick in the higher pressure flow mode, and you will only get a few hundred psi and a few gallons per minute.

Several yrs ago I had some 1st hand experience learning about CCLS hyd's that wasn't operating correctly on a Ford 5610 that I owned at that time. I prefer JD CC hyd's to CCLS hyd's

 

[LD1]

Have you ever diagnosed a malfunctioning JD CC hyd system?

Probably not to the extent that you have.

But yes I have worked on JD closed center systems that had hydraulic issues. But that was last decade so don't ask for specifics. The last one....ironically was a 2040. But that tractor has been gone since 2008 or 2009.

Again 80% of my experience is with industrial hydraulics. Which makes tractor hydraulics seem simple in comparison IMO.

Kinda like a 480v 3ph panel with a PLC, vfd's, numerous safety circuits....lots of eyes and prox's and other inputs/outputs and comparing it to a residential 120/240 household circuits where about the most complicated thing is a 3-way or 4-way switch

 

[Jimmy_G]

I agree with npalen in that knowing serial of JD 2040 with 3 cylinder engine is very important when it comes to hyd system. 3 cyl 2040's up to serial # 266,749 had OPEN-CENTER hyd's & after 266,750 had CLOSED-CENTER hyd's. Only reason I can think of for dealer to remove SCV is to sell the scv kit for more $$$$$. Post your tractors serial # & I'll help you diagnose/repair your tractors hyd problem. I would tell dealership to reinstall SCV or give it to you so you could sell the $750-$1000 kit if you don't want kit on tractor.

Serial number is 317012 L. Just got this thing back today. I bought it from a local fellow that has been buying and selling tractors for years and actually has a pretty good reputation locally. Unfortunately, he has not been all that helpful to me... FEL works fairly well, but, since getting it back I’ve noticed that, in addition to them pulling the rear remotes off, they left an open line that used to tie into the rear remote, and the 3 point hydraulics will not even let the box blade go all the way down (in addition to only lifting when the loader controls are used at the same time). Starting to feel like this guy saw me coming and just took my money.

 

[Tx Jim]

Your tractor has closed center hyd's. I think FEL control valve is open center OR if FEL valve has a relief valve it's not holding 2250 psi. Don't give up on tractor at this time. Can you please post photo of FEL control valve & photos of how hoses are attached to tractor hyd system?