2640 hydraulic issues

RoJoSmith · Jul 2, 2019

I have a 2640 that is giving me trouble. I have read many of the posts on the subject. One from June of 2016 by cowman79 best resembles my problem. I have a 240 loader mounted on my 2640.
it slowly creeps down, loader arms and bucket roll. The 3 point arms and control lever rise up on there own. The steering valve does leak and gets hot, O-rings are on order. Thanks to Tx Jim, and tim s for there advice on that. I have cleaned the screen and changed the Hyd filter, no smoking gun there. Now I'm going to show my ignorance. when looking in the Hyd filler hole I don't see anything special, no spraying ect., Should I?
In that 2016 post there was talk about the SCV, is that the control valve for the 3 point arms? Tx Jim posted that it was possible that the internal seal on the closed center plug had failed, where would I find that,? on the loader control? OK now you can laugh

Tx Jim · Jul 2, 2019

Welcome to YT
Closed center plug if present will be located in frt end loader control valve. No oil moving while looking in hyd filler hole behind seat is wonderful. Frt end bucket creeps down is more than likely caused by leaking internally loader control valve. 3 pt control lever has friction washers that is suppose to hold lever in set position until moved by operators hand.

Tim S will be along in a short amount of time to give you his shop location & contact info for cheap repairs. :lol:

Jim He-HE

RoJoSmith · Jul 2, 2019

Thanks Tx Jim. In the thread I referenced, someone mentioned a trouble shooting method for the loader control. Something like disconnecting the return line for the loader. If I understand correctly nothing should come out of the return line? Unless the loader control lever is moved? Is there an easy way to Identify pressure and return lines? Both lines come from under rear end. One from the bottom of the filter housing. Would the combination of the leaking steering valve and a bad loader control valve cause over heating?

buickanddeere · Jul 2, 2019

The good news is that the loader joystick valve is returned in the oil to a ported transmission filter cover .
As stated previously, there should be no oil flow in the return line back to the filter when no loader movement is selected .
If the joystick is open Center or if there is an O ring failure in the closed Center plug. Hydraulic function will be totally botched .

Tx Jim · Jul 3, 2019

As b&d stated remove quick coupler from hose that attaches to ported filter cover. Aim open hose in hyd filler hole or bucket,with FEL control valve levers in neutral operate engine briefly & if any oil comes out of hose something in FEL valve is leaking which causes tractor hyd's to not operate as designed.

RoJoSmith · Jul 3, 2019

Thanks Guys! If I find that the loader control valve is bad, can both types (open center, closed center) be repaired? I think I read tim s can do this repair.

Tx Jim · Jul 3, 2019

If loader control valve has a blown closed center plug seal or leaking relief valve those 2 things can probably be repaired. If spool to valve body is leaking then valve can't be repaired because that's a machined fit with very small tolerance.

RoJoSmith · Jul 4, 2019

(quoted from post at 03:03:02 07/03/19)
As b&d stated remove quick coupler from hose that attaches to ported filter cover. Aim open hose in hyd filler hole or bucket,with FEL control valve levers in neutral operate engine briefly & if any oil comes out of hose something in FEL valve is leaking which causes tractor hyd's to not operate as designed.

Followed your instructions today and was a flow of oil. I not a very good judge but I would say about a gallon a minute. Have I found my smoking gun?
Here are some photos of the loader control. Can anyone tell me if it is an open or closed center? do I need to do more trouble shooting to further isolate the problem?

[/img]

RoJoSmith · Jul 4, 2019

BTW Happy Independence day!

I hope no one is offended by my support for this great nation. And my American pride :x

Tx Jim · Jul 4, 2019

HAPPY INDEPENDENCE DAY to all members!

I did not see an open center valve or plug offered in 240 parts catalog. When you chocked for & located a 1 GPM leak was hyd oil at about 200 or hotter? Poppet valve(key 4) might be seating properly.

Tx Jim · Jul 4, 2019

Or spools/housing are worn allowing leakage.

RoJoSmith · Jul 4, 2019

Oil was not hot. Just disconnected quick couple removed pioneer fitting and stuck hose in fill port cranked up the tractor and ran for about a minute.

RoJoSmith · Jul 4, 2019

(quoted from post at 09:48:50 07/04/19)
HAPPY INDEPENDENCE DAY to all members!

I did not see an open center valve or plug offered in 240 parts catalog. When you chocked for & located a 1 GPM leak was hyd oil at about 200 or hotter? Poppet valve(key 4) might be seating properly.

Should I get the oil hot before the leak test? In your "Poppet valve(key 4) might be seating properly". did you mean Not seating properly?

Tx Jim · Jul 5, 2019

Higher temp oil will tend to leak more than colder oil. Yes I meant "not seating properly" but I'll bet the leak is between valve housing & spools.

RoJoSmith · Jul 5, 2019

(quoted from post at 14:59:35 06/07/16) Yes that would be one way, if yours has the short hose going to the rockshaft loosen the valve and pull it away,,stick a piece of heater hose on it and point it towards the fill hole, there should be little to no oil returning when in nuetrul or float..

I'm confused on component terminology. Is the SCV the rockshaft control or something else?

Tx Jim · Jul 5, 2019

SCV=selective control valve AKA valve with rear hyd outlets AKA rear remotes

buickanddeere · Jul 5, 2019

The joystick valves on my 240loader and 1640 will seep enough oil through them to melt snow .

RoJoSmith · Jul 5, 2019

Got it. Can't say for sure but I don't think mine have seen much use. In the eight years I've had it I have never used them.
Even though I don't use them, could they still cause me problems?

RoJoSmith · Jul 5, 2019

Got my O-rings for the steering valve today, will tear into that Sunday after church. Maybe God will have pity on me. He knows what a sinner I become when working as a mechanic.

RoJoSmith · Jul 5, 2019

My hart felt thanks to you all for taking the time to help this ignoramus.

Tx Jim · Jul 6, 2019

(quoted from post at 18:53:16 07/05/19) Got it. Can't say for sure but I don't think mine have seen much use. In the eight years I've had it I have never used them.
Even though I don't use them, could they still cause me problems?

No likely to be hyd problem but could be. To check SCV for internal leaking one can loosen mounting bolts then remove short hose between SCV & RS housing & with levers in neutral with engine running no oil should exit hose barb.

RoJoSmith · Jul 8, 2019

Replaced the O-rings in steering valve to day. Nothing really jumped out at me put it back together and steering was still difficult. I disconnected the lines for the loader and steering was much improved. The time hen I have the most trouble is when brush hogging so I'm going to completely remove the loader, hook up the mower and see what happens. In the past everything gets hot and hydraulic get erratic

buickanddeere · Jul 8, 2019

Unless the loader hydraulics are supplied from a T in the high pressure line . To a loader joystick with a functional, non leaking closed centre valve . And the loader oil retuned via a ported transmission filter. The tractor hydraulics WILL NEVER operate properly.
I have to ask. Do you know the difference between closed centre and open centre hydraulics ?

RoJoSmith · Jul 8, 2019

(quoted from post at 07:47:40 07/08/19)
Unless the loader hydraulics are supplied from a T in the high pressure line . To a loader joystick with a functional, non leaking closed centre valve . And the loader oil retuned via a ported transmission filter. The tractor hydraulics WILL NEVER operate properly.
I have to ask. Do you know the difference between closed centre and open centre hydraulics ?

o sir I do not. I know very little about Hydraulics. I do believe it is plumbed the way you described except for the functional valve. I have removed the valve and am hoping to find an honest trustworthy repair person to take it to.

Tx Jim · Jul 8, 2019

Which valve have you removed? If it's the FEL control valve that you stated was leaking internally my advice would be just throw valve in trash & buy a new valve.

RoJoSmith · Jul 8, 2019

Just talked to JD parts. Valve is obsolete. A new valve is available for over 2K. Any other options. The old valve was a two spool cesna.

RoJoSmith · Jul 8, 2019

Yes it was the FEL valve.

Tx Jim · Jul 8, 2019

(quoted from post at 15:34:29 07/08/19) Just talked to JD parts. Valve is obsolete. A new valve is available for over 2K. Any other options. The old valve was a two spool cesna.

I never meant to imply to get a valve from JD. They purchase their valves from a manufacturer then add their profit to price. Here's a valve for a little over $200. You'll also need a closed center plug & seals plus 2300 PSI relief cartridge.

RoJoSmith · Jul 8, 2019

(quoted from post at 14:35:31 07/08/19)

(quoted from post at 15:34:29 07/08/19) Just talked to JD parts. Valve is obsolete. A new valve is available for over 2K. Any other options. The old valve was a two spool cesna.

Click to expand...

I never meant to imply to get a valve from JD. They purchase their valves from a manufacturer then add their profit to price. Here's a valve for a little over $200. You'll also need a closed center plug & seals plus 2300 PSI relief cartridge.

Wow that's a relief. I just thought that with my limited knowledge it would be better to go back with with the same item but for an $1800 price difference I can get educated.
Ran the tractor all day today without the loader mounted, and had no problems. I pray changing the FEL valve will solve my problems.

Tx Jim · Jul 8, 2019

There may be a valve available that fits your application better than the valve I quickly picked out.

radara4077 · Jul 14, 2019

I'm going to jump in here to say thank you all so much for being willing to put up with us less knowledgeable folks on these otherwise-wonderful Mannheim Machines.

I think this gentleman's loader issue is also plaguing my 2550, based on what meager knowledge I've gained about the hydraulics on these tractors, and on the symptoms our tractor has been exhibiting (separate--or perhaps not--from the front pump leak issue about which I just posted).

I don't think you gentleman hear this enough, but I and I'm sure many others sincerely thank you.

RoJoSmith · Jul 21, 2019

I have ordered a new FEL control valve. While I'm waiting for it, I have removed the loader from the tractor and have used it for some activity's like brush hogging and cutting hay with the sickle bar. Everything works better with the loader off so I'm hopeful a new FEL control valve will be the answer. However today I was working on some equipment maintenance with the tractor idling and noticed the steering valve was very warm almost hot. I have replaced the six O-rings in the valve and am certain they all went in correctly. I'm wondering, can a component (say the steering valve)
be working properly without any malfunction, and get hot because of a problem in a completely different component(say the SCV)?
Or is it, if the steering Valve gets hot there is a problem with the steering valve?

buickanddeere · Jul 21, 2019

(quoted from post at 13:23:59 07/21/19) I have ordered a new FEL control valve. While I'm waiting for it, I have removed the loader from the tractor and have used it for some activity's like brush hogging and cutting hay with the sickle bar. Everything works better with the loader off so I'm hopeful a new FEL control valve will be the answer. However today I was working on some equipment maintenance with the tractor idling and noticed the steering valve was very warm almost hot. I have replaced the six O-rings in the valve and am certain they all went in correctly. I'm wondering, can a component (say the steering valve)
be working properly without any malfunction, and get hot because of a problem in a completely different component(say the SCV)?
Or is it, if the steering Valve gets hot there is a problem with the steering valve?

The power steering columns on those do operate surprisingly warm.
My 1640 is starting to make moans and groans from the rock shaft depending on the height setting. Old Bessie is probably coming due for a kit.

RoJoSmith · Jul 23, 2019

If replacing the FEL control valve doesn't improve things that's the next place I'm going. I'm working on the loader control valve today. From the loader control valve the lines go strait to the boom cylinders boom but the bucket lines go through a relief valve. Anyone know why, could it be bypassing, can it be rebuilt, if I bypassed the relief valve would I do damage to the bucket cylinders, the list of questions goes on and on

.

Tx Jim · Jul 23, 2019

Yes pressure control valve could be faulty.

tim s · Jul 23, 2019

Remove the return line from the valve and head it to a Bucket start the tractor and don't touch the control valve,,if you have oil flowing into the bucket the valve is at fault,, no oil flowing into the bucket the valve is probably okay....There are several possible causes to your issue...

RoJoSmith · Jul 25, 2019

Replaced the FEL control to day, installing a three spool valve. It functions but a little funky. The pressure line pulsates like a heart beat. There is no outflow from the return line with controls neutral. I got a 5000 PSI gauge, put it on the the return line for the third function control. With the tractor running I activated the control and got 1500 PSI. Then put the gauge on a pioneer couple and checked all the SCV all read 1500 PSI. Not sure I did it correctly but that seems low.

Tx Jim · Jul 26, 2019

Factory hyd stand-by pressure is 2250 psi.

buickanddeere · Jul 26, 2019

(quoted from post at 20:17:47 07/25/19) Replaced the FEL control to day, installing a three spool valve. It functions but a little funky. The pressure line pulsates like a heart beat. There is no outflow from the return line with controls neutral. I got a 5000 PSI gauge, put it on the the return line for the third function control. With the tractor running I activated the control and got 1500 PSI. Then put the gauge on a pioneer couple and checked all the SCV all read 1500 PSI. Not sure I did it correctly but that seems low.

Pressure was measured with there was oil flow or no oil flow while on standby ?
If measuring from one of the third valve s outlet when it is connected only to a gauge . That would measure system pressure while that third valve has the lever to that gauge port pulled .
The oil being supplied to the loader valves is connected down stream of the power steering priority valve ?
I am still wondering if that front pump is not being supplied with enough oil from the transmission oil circuit ?

RoJoSmith · Sep 12, 2019

Now I'm going through the step by step hydraulic trouble shooting in the manual. It took forever to get all the correct fittings since the manual gives the wrong sizes for most of the connections. After hooking up all test equipment, The first test is step 3 and it failed.
Having a greater than 3 PSI increase at the inlet when destroked.
Next step was to cap power steering supply and testing again. this time there was the proper 3 PSI increase. The instructions are to repair the steering valve and test again. I have already replaced the 6 O-rings in the steering valve, and I have read that rebuilding the steering valve is not a job for amateurs. I have to imagine buying a re-man assembly would be near impossible. What is a poor farmer to do. Please don't say blow it up. That's not an option.

2640 hydraulic issues

Member

Well-known Member

Member

Well-known Member

Well-known Member

Member

Well-known Member

Member

Member

Well-known Member

Well-known Member

Member

Member

Well-known Member

Member

Well-known Member

Well-known Member

Member

Member

Member

Well-known Member

Member

Well-known Member

Member

Well-known Member

Member

Member

Well-known Member

Member

Well-known Member

Member

Member

Well-known Member

Member

Well-known Member

Well-known Member

Member

Well-known Member

Well-known Member

Member

Similar threads