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?

 

[Zebrafive]

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.

When you say "just got it back today" did you return it for any changes?
Like change the loader valve to CC (closed center)?
Did you agree to buy it without rear remotes? Did they remove the SCV and quick couplers?
More info on the line they left open. If it is coming from the PCV and unplugged it will be flowing!

 

[Jimmy_G]

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?

These are the only pictures I have at the moment. I’ll get better ones tomorrow evening when I am back out there. It sprung a leak from one of the hoses yesterday so it’s going to be down until I get that replaced anyhow.

 

[CADplans]

I'm not understanding this as it sounds like you're describing a leak in the suction line not allowing sufficient fluid into the pump causing cavitation. That would be true with either type of valve, no? (I may be misinterpreting.)

The CC pump has a huge volume capacity compared to the same size tractor with an open center system

 

[CADplans]

The CC pump has a huge volume capacity compared to the same size tractor with an open center system

and the CC pump ONLY has to supply that huge volume capacity when the controls are set to supply the oil for some use.
Otherwise, the CC pump is not pumping hardly any oil.

So, installing an OC valve in a CC system causes the tractor to pump huge volumes of oil,, which is wasted effort demanded of the tractor.

If the oil does not get back to the sump (usually the transmission) fast enough,, the pump starts to suck air.
The CC system is not designed to pump 100% of the flow capacity constantly.

If the CC system was designed for 100% function, the transmission would hold 3 or 4 times as much oil.

 

[Jimmy_G]

and the CC pump ONLY has to supply that huge volume capacity when the controls are set to supply the oil for some use.
Otherwise, the CC pump is not pumping hardly any oil.

So, installing an OC valve in a CC system causes the tractor to pump huge volumes of oil,, which is wasted effort demanded of the tractor.

If the oil does not get back to the sump (usually the transmission) fast enough,, the pump starts to suck air.
The CC system is not designed to pump 100% of the flow capacity constantly.

If the CC system was designed for 100% function, the transmission would hold 3 or 4 times as much oil.

I’m assuming that’s why it sounds almost like it has cavitation (tapping sound) in the lines when you operate the loader?

 

[Tx Jim]

I can't determine for sure from photos but the hyd valve in photo I think is a closed-center valve. A better photo of valve & knowing how valve is connected to tractor hyd system is important.

Simple test: disconnect FEL hyd valve return hose from tractor, cap that fitting on tractor. With FEL control lever in neutral start engine, aim open hose in open hyd filler hole behind seat & no oil should escape open FEL control valve return hose. I think CC valve in photo is what you have.

 

[Jimmy_G]

When you say "just got it back today" did you return it for any changes?
Like change the loader valve to CC (closed center)?
Did you agree to buy it without rear remotes? Did they remove the SCV and quick couplers?
More info on the line they left open. If it is coming from the PCV and unplugged it will be flowing!

It’s a long story. Basically bought the tractor on a handshake from a local guy with a good rep. I don’t believe he sold it to me maliciously, but he didn’t check it out the way he promised to either this is back in October. I used it the first day, scooped a load of sand (not even a full bucket) and blew one of the lift cylinders for the FEL - shooting white hydraulic fluid everywhere. I called him and he had me bring it back so he could put new seals in the cylinder and change the hydraulic fluid. I got it back just before Thanksgiving.
Then I hooked onto the box blade and was going to work with it, only to find that the hydraulics would not lift for the three point. I called him again, and we found that the FEL had an open center valve, and that the three point would lift if you could move the FEL controls. He couldn’t get to it right then and asked me to bring it to him after the first of the year. In the interim, we noticed that all three FEL cylinders that we had not rebuilt were leaking too, so I had him do those - now, it’s March, I’ve picked it up, and the cylinders don’t leak anymore, but he decided not to do anything about the open valve on a closed system because it’s not a simple fix. In the process of testing and diagnosing, he removed the rear remote, and cut the lines. There is a line attached to the spot where there is a plug just to the left and below the cap for the hydraulic oil that is no longer attached to anything. The three point will not go all the way down, and the hydraulic fluid is milky white again - as I noticed when one of the lines started shooting hydraulic oil several feet in the air from one of the fittings on the FEL.
All in all, a pretty frustrating experience.

 

[Jimmy_G]

I can't determine for sure from photos but the hyd valve in photo I think is a closed-center valve. A better photo of valve & knowing how valve is connected to tractor hyd system is important.

Simple test: disconnect FEL hyd valve return hose from tractor, cap that fitting on tractor. With FEL control lever in neutral start engine, aim open hose in open hyd filler hole behind seat & no oil should escape open FEL control valve return hose. I think CC valve in photo is what you have.

I will get you some better pictures tomorrow afternoon. I really appreciate you taking the time to look this over and to help. This is been a pretty frustrating experience for me but I really would like to keep this old tractor running and use it.

 

[Zebrafive]

I can't determine for sure from photos but the hyd valve in photo I think is a closed-center valve. A better photo of valve & knowing how valve is connected to tractor hyd system is important.

Simple test: disconnect FEL hyd valve return hose from tractor, cap that fitting on tractor. With FEL control lever in neutral start engine, aim open hose in open hyd filler hole behind seat & no oil should escape open FEL control valve return hose. I think CC valve in photo is what you have.

TxJim, I think it's an open center valve. Key 21 is where another hose would connect. I am not sure if that is the "tank/return" hose or PB (power beyond) hose that connects there. I am guessing it has plug in it.
I do not know if there is a special cc conversion plug for this port.

Your test of disconnecting the return hose would confirm if OC or CC.

 

[Zebrafive]

It’s a long story. Basically bought the tractor on a handshake from a local guy with a good rep. I don’t believe he sold it to me maliciously, but he didn’t check it out the way he promised to either this is back in October. I used it the first day, scooped a load of sand (not even a full bucket) and blew one of the lift cylinders for the FEL - shooting white hydraulic fluid everywhere. I called him and he had me bring it back so he could put new seals in the cylinder and change the hydraulic fluid. I got it back just before Thanksgiving.
Then I hooked onto the box blade and was going to work with it, only to find that the hydraulics would not lift for the three point. I called him again, and we found that the FEL had an open center valve, and that the three point would lift if you could move the FEL controls. He couldn’t get to it right then and asked me to bring it to him after the first of the year. In the interim, we noticed that all three FEL cylinders that we had not rebuilt were leaking too, so I had him do those - now, it’s March, I’ve picked it up, and the cylinders don’t leak anymore, but he decided not to do anything about the open valve on a closed system because it’s not a simple fix. In the process of testing and diagnosing, he removed the rear remote, and cut the lines. There is a line attached to the spot where there is a plug just to the left and below the cap for the hydraulic oil that is no longer attached to anything. The three point will not go all the way down, and the hydraulic fluid is milky white again - as I noticed when one of the lines started shooting hydraulic oil several feet in the air from one of the fittings on the FEL.
All in all, a pretty frustrating experience.

Pictures will help. The ones TxJim asked for of how/where the loader valve connects to the tractor. Also what is left of the rear remote, and the cut line.

I may have missed what transmission and type of PTO it has. If Hi/Lo or Reverser transmission, I would be very worried the white/milky hydraulic fluid (water in fluid) has ruined the clutch packs. Same for clutch pack if it has IPTO Independent PTO (operated be control between shift levers, not foot clutch). Water in fluid will also ruin the brake linings.

Was tractor stored outside? Are the shift boots cracked/torn? They are a primary entry point for water when they are damaged. Sump screen should be checked for brake/clutch lining material.

I would want a correct cc loader valve installed and rear remote(s) restored to working order. Plus some agreement how brakes and wet clutches (if equipped) will be addressed if damaged.