# JD2140 Hi/low shift cover. Help needed.



## Lindsay Smith (Sep 12, 2019)

I need help to work out how to assemble the hi/low control lever cover on a JD2140 with SG cab. We had to remove the top of the gear box to adjust the transmission pressure as it was low. However in the process the balls on the detent on the pto lever have dislodged. I am having problems assembling it as there are 4 ball bearings, springs, etc that have to be installed all at once. Looks impossible to assemble it as too many things to do at the same time. JD manual no help. Can anyone give me a clue how to do it. Why do they make it so difficulty when will a little more effort they could make it impossible! Hope someone can help.:tango_face_crying:


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## pogobill (Jan 31, 2012)

Welcome to the forum Lindsay Smith. I have no idea how to help, but I'm sure someone here surely can. 
Would it be possible to use a very slight film of grease to stick the springs and ball bearings together to help with assembly? Not sure if this would impact your hydraulic oil, or is it external to the reservoir?


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## Lindsay Smith (Sep 12, 2019)

pogobill said:


> Welcome to the forum Lindsay Smith. I have no idea how to help, but I'm sure someone here surely can.
> Would it be possible to use a very slight film of grease to stick the springs and ball bearings together to help with assembly? Not sure if this would impact your hydraulic oil, or is it external to the reservoir?


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## Lindsay Smith (Sep 12, 2019)

Thanks. I have unsuccessfully tried that. I may try to use silicone and allow to dry.


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## pogobill (Jan 31, 2012)

I'm sure someone will stop by with an idea to help. Some pictures may help folks understand exactly what you are up against.


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## pogobill (Jan 31, 2012)

Lindsay Smith said:


> Thanks. I have unsuccessfully tried that. I may try to use silicone and allow to dry.


Make sure that the silicone doesn't compromise any sealing effects that the detent balls may have......


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## Fedup (Feb 25, 2014)

Silicone is not a good idea. I wouldn't want to introduce that into any hydraulic passages. I'm not sure why you removed the entire shift cover. It's my understanding the shims in the regulating valve can be accessed without that. What was the initial problem with the tractor? In my experience low transmission pressure is most often caused by internal leakage somewhere in the system, not the pressure regulator. I've had a few of those covers off and don't recall ever having the problem you're describing with balls and springs.


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## Lindsay Smith (Sep 12, 2019)

Fedup said:


> Silicone is not a good idea. I wouldn't want to introduce that into any hydraulic passages. I'm not sure why you removed the entire shift cover. It's my understanding the shims in the regulating valve can be accessed without that. What was the initial problem with the tractor? In my experience low transmission pressure is most often caused by internal leakage somewhere in the system, not the pressure regulator. I've had a few of those covers off and don't recall ever having the problem you're describing with balls and springs.


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## Lindsay Smith (Sep 12, 2019)

Thanks for your reply. Yes I don't like silicone either but at wits end. Normally you can change the pressure without out removing the cover however on a SG Cab tractor it would have been impossible to reinstall the plug with the 2 strong springs. Would have been OK if no cab. The tractor on idle has got low transmission pressure ie. around 50psi. At full revs it is around 140psi. (should be 150psi at 1500rpm or better). At idle the PTO still turns when it is disengaged, the power steering fails, the high low shift does not work and the 3 point lift is shaky. If you rev the tractor to over 1000rpm everything seems OK. I have had this problem on many JD tractors over the years. It could bee an internal leak or it could be a worn transmission oil pump. All the filters and oil has been changed. The picture shown is not the correct one as this one has another lever for hi/low. I can't find the correct one on JDParts. However it shows the springs and balls in question. Pity they didn't use an extra plug for access.


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## Fedup (Feb 25, 2014)

Okay so trans pressure is low. Measured where? Usually when I check pressures I put a gauge in the test port at the right front corner of the shift cover. 

Then run the engine at 1200 or so and read the pressure. Then shift PTO on then off a few times to see what if anything changes. Same again with hi/lo, 4WD or any other functions supplied with transmission oil pressure. If there is a leak in any of those circuits the pressure will be noticeably less when that function is engaged particularly at the lower RPM. I think the book calls for 1500 or more. Not sure on that. 

The hi/lo is not working. Meaning it won't drive in one range or the other? Slips under load? Won't shift? ???

I trust you checked the pump suction screen and trans pump relief valve before tearing into it?


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## Lindsay Smith (Sep 12, 2019)

Finally achieved success. I did not use any silicone. I greased up the plungers so they would stay on the blind hole. The ball was greased in place as well. More grease around the spring. Placed the ball on the spring with pointy nose pliers and compressed in place with a kitchen knife while inserting the arm behind it. Once the ball slotted into the detent hole everything then went to plan. Put the other plunger in and then the plug and then the second ball and spring and its plug. All good but the result was disappointing. I put 3 extra shims in to increase transmission pressure. At idle it was reading around 60psi. At 1000rpm it was reading around 110psi. At this point the pto brake worked and the pto stopped. At full revs it was reading just under 150psi. There was not much improvement which suggests that there is a lack of oil flow. As a temporary measure I have increased the idle speed to 1000rpm until I am sure of the problem. Everything seems to work OK like this.
At full revs when the pto is turned on/off the pressure gauge drops and quickly returns. When the hi/low shift is actuated the pressure drops substantially more then returns to the original figure. I have not checked the power steering to see if there are any leaks there.
I am a little concerned that the transmission oil pump may be showing some wear and unable to supply enough oil at low revs. If there was plenty of oil flow by adding more shims to the relief valve I would expect a pressure increase. Other similar tractors using this system that I have worked on over the years have responded with a pressure increase. The tractor has done around 7000hrs. Any other comments appreciated.


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## Lindsay Smith (Sep 12, 2019)

Sorry forgot to mention oil filter and screen changed and cleaned. This tractor has got a device hooked to the transmission flow that from memory if the pressure is low is goes to low range. This seems OK. No known slippage of the clutch/brake drive discs but at low pressure I would assume they would slip under heavy load.


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## Fedup (Feb 25, 2014)

That's not exactly a "devise". What it has is a hi/lo clutch in which low range is spring applied (in a way somewhat similar to an engine clutch), and high range is engaged by hydraulic pressure. There are two pistons that move when you shift to high. One engages the high range clutch pack, the other releases the low range clutch pack. Leaks in either one can cause a low pressure situation. The shift valve has a hydraulic detent when in high range. If the pressure falls below a certain point it will default to low range. Since low range requires no hydraulic pressure to engage, if it slips under load it can only be worn plates. 

Have you tried the transmission relief valve? I've seen cases where that has been a factor with problems such as yours. It's just a spring loaded ball and seat type thing but it can bleed off oil flow in the system if it gets a piece of something wedged and fails to seat properly.


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## Lindsay Smith (Sep 12, 2019)

Is the valve you are referring to the one that bypasses the transmission filter if blocked? I am having problems finding it in JDParts. I think it is located just above the filter. Strange thing with this tractor is the farmer used it before the winter and everything worked fine. About 3 months later when used next the problem arose. That is my doubt about if it is a worn transmission pump as it would progressively get worse.


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## Fedup (Feb 25, 2014)

You're right on the location. It will be under a plug above and to the right of the filter can. The plug is threaded into the main case casting. It will gush a quantity of fluid when removed so I don't usually remove it entirely unless I'm draining the system anyway. I remove the plug, let the spring release it's compression, and let some oil flow out. Then push it all back into place. That's often enough to flush the culprit piece of debris (if that's the problem). It might make a difference.

Your fears about the pump make sense, but in most cases the low pressure is a result of something other than a worn pump. I don't do a lot of Deere hydraulic problems, mainly on 30, 40, 50, and 55 series. Nothing newer than that. I've yet to replace a transmission pump. It's always been something else. I'm working on 2755 right now with similar issues. His problem is pretty much all in the hi/lo clutch area. Have it scattered now and working on gathering parts for it. Symptoms were much like yours when hi range was engaged pressure was low, hydraulics making noise, steering failure, three point jerky. Sound familiar?


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## Lindsay Smith (Sep 12, 2019)

Thanks for your thoughts. I have changed maybe 5 or 6 transmission pumps over time due to wear. JD1020, 2120, 2130 and JD400 loader/backhoe. I will check the pressure relief valve when I get time. I think I may have had problems with one on a JD2020 many years ago. I will also put the gauge back on and watch what happens with hi/low when it is operating. I was going to leave the gauge on for a while so the operator could watch it but I had to remove it as the foot throttle was interfering with it. The mystery continues.


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## jd110 (Nov 23, 2015)

Lindsay Smith said:


> Is the valve you are referring to the one that bypasses the transmission filter if blocked? I am having problems finding it in JDParts. I think it is located just above the filter. Strange thing with this tractor is the farmer used it before the winter and everything worked fine. About 3 months later when used next the problem arose. That is my doubt about if it is a worn transmission pump as it would progressively get worse.


This is a pic of the filter relief valve. It is a cartridge type valve. one of the roll pins may be broken or a piece of dirt could have the valve held off of its' seat. I thinke the valve that Fedup is describing is actually what I call the surge relief valve or cooler relief valve. It is closer to the brake valve. Both plugs to access valves are 1 1/4" wrench size. or 32 mm.


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## Lindsay Smith (Sep 12, 2019)

I have finally got around to checking the filter dump valve. The spring(L33358) has been damaged on one end for some reason. No other faults found. I did some more checks on transmission oil pressure. At 1000rpm in hi range pressure was 108psi. In low it was 110psi. When you change from hi to low pressure drops to 60 then slowly increases to 108psi. At 1500rpm pressure in hi is 132psi, in low it was 133psi. When you change to hi it drops to 85 then returns back to 132psi. At 2500rpm pressures were hi 138 and low 140psi. The dash pressure light goes out at 120psi @1150rpm in lo and [email protected] in hi. Light goes out with pto on @[email protected] The 3 point linkage continues to lift with jerks. Not smooth as normal. Still looks like a transmission pressure oil leak. Not sure where to look next.


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## Fedup (Feb 25, 2014)

I think your pressures are indeed low. You've already added shims to the regulator valve and still can't get the pressure up to 150 psi? Could be a weak pump, yes, but could also be an internal leak. Cracked line, dried out and leaking O ring(s), something like that. You've already had the shift cover off and apart so I'm guessing the seals and gaskets under there have been checked/changed so the problem shouldn't be there.

I would suggest eliminating the high pressure circuits one at a time just to see what difference (if any) that makes before splitting the tractor. There is a procedure for testing the flow of the transmission pump, but it's a bit involved. It's laid out in the I&T manuals, but I've never actually done it. I have a flow meter but have yet to use it in this case. 

The 2755 I mentioned earlier is now back together. The clutches are all working, pressure is steady at 155 now in all functions, but the charge pressure was still low. I then started eliminating circuits. Simply by removing the line supplying oil to the functions and capping the fittings. Easy to do with a closed center system. First the remote valve, which produced no change. Next the steering valve. When I took the steering out of play the standby pressure went from 500 psi at idle to 2000. Charge pressure at the front pump went from 5 psi to 30. I was using a 0 - 80 psi gauge in the charge line. When the rpm was raised to 1200 or so the charge pressure pegged the gauge. That tells me the steering valve was the cause of the problems all along. Should have a new steering valve on it today and will see what happens next.


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## Lindsay Smith (Sep 12, 2019)

Fedup said:


> I think your pressures are indeed low. You've already added shims to the regulator valve and still can't get the pressure up to 150 psi? Could be a weak pump, yes, but could also be an internal leak. Cracked line, dried out and leaking O ring(s), something like that. You've already had the shift cover off and apart so I'm guessing the seals and gaskets under there have been checked/changed so the problem shouldn't be there.
> 
> I would suggest eliminating the high pressure circuits one at a time just to see what difference (if any) that makes before splitting the tractor. There is a procedure for testing the flow of the transmission pump, but it's a bit involved. It's laid out in the I&T manuals, but I've never actually done it. I have a flow meter but have yet to use it in this case.
> 
> The 2755 I mentioned earlier is now back together. The clutches are all working, pressure is steady at 155 now in all functions, but the charge pressure was still low. I then started eliminating circuits. Simply by removing the line supplying oil to the functions and capping the fittings. Easy to do with a closed center system. First the remote valve, which produced no change. Next the steering valve. When I took the steering out of play the standby pressure went from 500 psi at idle to 2000. Charge pressure at the front pump went from 5 psi to 30. I was using a 0 - 80 psi gauge in the charge line. When the rpm was raised to 1200 or so the charge pressure pegged the gauge. That tells me the steering valve was the cause of the problems all along. Should have a new steering valve on it today and will see what happens next.


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## Lindsay Smith (Sep 12, 2019)

Yes I think you are on the right track with this. On older JD tractors such as a 2130 or 400 backhoe with the different type of column steering I have had this problem many times. Never on a cab tractor. Will look at that when I get a new spring for the bypass valve.


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## Lindsay Smith (Sep 12, 2019)

Trying to find the pressure line to disconnect the power steering on this SG Cab 2140 tractor. Is that the one that connects to the pressure control valve above the hydraulic filter. I have not got the correct service manual for this tractor. I have got a bad hip and having trouble getting down to properly search. I have got a new bypass spring for the 2140 coming next week. I can't do much more until I get it. I hope Fedup solves the problem with a replacement steering valve.


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## Fedup (Feb 25, 2014)

I'm no expert on these tractors but USUALLY the pressure line from the piston pump follows along with the charge and lube lines along the frame on the right side of the tractor. Charge and lube lines are 5/8", the pressure is 1/2". The charge and lube lines connect to the clutch housing at the tractor split area, the pressure line continues on. At this point there is a tee in the pressure line for the steering supply line going up into the column area. That's where you disconnect the steering supply and cap the tee with whatever caps/plugs you can come up with. On some tractors this is standard J.I.C. fittings, but more often it's a metric compression tube type. Finding fittings to match these can be a challenge. I try to save all the hose ends and fittings I can from German built Deere tractors to make caps, plugs, adapters etc because many hydraulic fitting outlets don't stock them.

From there the line goes to a priority valve mounted on the rear main housing near the filter housing. The supply to the lift housing is a port behind that with no external access. To eliminate the the lift system you must remove and plug the line between the steering tee and this valve. This also eliminates the remote valves because they are supplied with a line between the priority valve and the remote valve(s). I would eliminate the remotes first and see what if anything changes. Steering next, and lift circuit last. If nothing changes and your transmission circuit is still unsatisfactory you may have to go inside.


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## Lindsay Smith (Sep 12, 2019)

Thanks for the advice. Once I get the new spring on the bypass valve I will keep looking.


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## Lindsay Smith (Sep 12, 2019)

I have finally got around to fitting the new spring in the filter bypass valve. Unfortunately there is no change to my transmission pump pressure. I then blocked the power steering circuit. Again no change. Then I blocked the 3 point linkage and remotes from the pressure line. Again no change. The transmission pressure is still too low to activate hi/low change, pro, etc if the engine revs are below around 1100rpm. It goes up to around 140psi at full revs. The hi/low shift appears to operate OK and no signs of slippage. If you have it on a slasher and the revs drop to 1100rpm the pto stops. Looks like and internal leak or the transmission pump worn. I know the owner has lately replaced the transmission oil with a multi purpose hydraulic oil. Wondering if a higher viscosity oil may help but not solve the leak? Sounds like a cab off exercise.


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## pogobill (Jan 31, 2012)

I'd try and find out what oil the previous owner used, and if it doesn't meet specs, put in the real mccoy.


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