John Deere 160clc slow and week functions intermittent

[The Dirt Guy]

Equipment: 2003 John Deere 160CLC.

History: I replaced the engine with a used one, machine worked fine and noticed my boom up slowed way down and at the same time I had an oil pan gasket leaking (must have torn it when I installed it). I replaced the arm regenerative solenoid and went to work; it corrected the boom speed, and I was able to continue on. I then decided to have Deere come and change the oil pan gasket and install engine wiring harness since the current one was in bad shape. Once they left, I ran the machine for approximately 3hrs before I noticed no arm in power and functions were operating slowly. Arm in function blew a line from the control stick, replaced it and called Deere again. Deere stated that they adjusted the main relief and replaced some O-rings. Went to pick it up and it started and ran fine so I loaded it up and brought it home, ran it for 3-5hrs and all functions went slow and no power Hydraulic wise (everything operated very slow). When the bucket teeth were in the ground it would not even scratch the soil. I contacted another local mechanic and we found the main relief would not adjust so I bought a new one verified the pressure was at the desired level approximately 5000 psi on the display control, I then assumed great so I decided to run it, it ran for 1-2hrs before reverting back to the old way of slowing everything down all functions and no hydraulic power again, engine rpm stayed normal 2010rpm ( I know this is slightly low according to spec but this is what it has been the whole time). I then decided to look at a gauge installed on the pilot manifold and at low idle it was reading 0psi and at high idle it was at 325-400psi. this was unusual since it had normally been at 500psi regardless of the idle speed when the machine was operating normally.

Issue: Hydraulic issues, pumps 1 and 2 will display approximately 5000 psi and suddenly drop to 2700 psi and all function will reduce in power. Pilot pressure at full throttle is approximately 325-400psi and at idle 0psi. No codes on display or pump controller under the back console. Also, while checking the boom up and arm in pressure displacement for pumps 1 & 2, the function will drift on occasion which had never happened before (drift does not occur every time).

Items replaced: 4045T engine (used), engine wiring harness, pump 1 & 2 pressure sensor, arm regenerative solenoid, main relief valve, boom up pressure sensor, arm in pressure sensor, crankshaft speed sensor, hydraulic pump speed sensor, verified all voltage reading on all sensors on the pump were within the spec. Arm in, boom up, and another line relief was removed and cleaned and packing and O-rings replaced then reinstalled. (John Deere stated the main pump was good when I took it to the shop).

Need help addressing, thank you in advance for the input.

 

[Diesel Dave]

Is it safe to assume the full throttle pilot pressure remains at approximately 325-400psi regardless if the hydraulics are acting up or not ?
If pilot pressure is not the true issue ,I would suspect the hydraulic controller behind the seat has an intermittent loss of power or ground.Check fuse connections, controller connectors and grounds.

 

[The Dirt Guy]

Yes you are correct in assuming the pressure stays the same whether or not hydraulics are in use or not.

I will recheck grounds and fuses in the morning.

 

[mg2361]

If your engine harness was that bad, I would be suspicious of the machine harness as well. I wonder if there is an issue with the speed solenoid circuit wiring or the solenoid itself. Also, if the engine speed sensor circuit ever shows 0 rpm, then the controller will destroke the pumps. I know you said you replaced the speed sensor, but did the wiring for it get checked thoroughly or replaced?

 

[The Dirt Guy]

Is it safe to assume the full throttle pilot pressure remains at approximately 325-400psi regardless if the hydraulics are acting up or not ?
If pilot pressure is not the true issue ,I would suspect the hydraulic controller behind the seat has an intermittent loss of power or ground.Check fuse connections, controller connectors and grounds.

Verified grounds were tight and clean.

 

[The Dirt Guy]

If your engine harness was that bad, I would be suspicious of the machine harness as well. I wonder if there is an issue with the speed solenoid circuit wiring or the solenoid itself. Also, if the engine speed sensor circuit ever shows 0 rpm, then the controller will destroke the pumps. I know you said you replaced the speed sensor, but did the wiring for it get checked thoroughly or replaced?

View attachment 274593

Y5 is new verified today that it was working and yes you are correct the wiring could be the culprit but I’m having issues with locating a harness but…I have verified voltage at the plug.

 

[Diesel Dave]

When in service mode you mentioned the (2) pump pressures drop from 5000 to 2700 PSI when the issue is occurring.
Like MG2361 suggested that you keep an eye on engine speed ever showing 0 rpm.
Is there any other live data you see that is significantly lower or higher or non existent when the issue is occurring compared to normal operation ?

 

[LACHAU]

Equipment: 2003 John Deere 160CLC.
Issue: Hydraulic issues, pumps 1 and 2 will display approximately 5000 psi and suddenly drop to 2700 psi and all functions will reduce in power. Pilot pressure at full throttle is approximately 325-400psi and at idle 0psi. No codes on display or pump controller under the back console. Also, while checking the boom up and arm in pressure displacement for pumps 1 & 2, the function will drift on occasion which had never happened before (drift does not occur every time)

What do you mean by "PILOT PRESSURE"? Where did you measure pilot pressure???

 

[The Dirt Guy]

Pilot pressure is supplied by the pilot pump in relation to main pumps 1 and 2. All three are utilized on the machines hydraulic system to function properly. Pilot pressure is checked at one of these two spots circled below, I don't remember which one, but this is where the service manual says to install you can also check pilot pressure on the pilot control manifold as well but there is a reason for that, but I don't have the service manual in front of me to quote why.

Also, verified using a new gauge over the weekend and my pilot pressure is 500-600psi at full idle and at low idle 250ish psi. My gauge must have failed. I worked through the display and when verifying pump 1 and 2 pressures, it would occasionally hit 5000psi but never would hold, all other pressures appear to be in spec except for pump 1 and 2. I do believe the HP mode will not engage due to the inability of the pumps making the psi required for the ecm to notice and engage HP mode. This can be verified later once the pressures are straightened up.

I blocked off some of the machine's functions to see if it would isolate the issue and show correct pump readings on the display, but none were successful. I did stall each track out and isolated each pump and I did receive 5000psi readings but as I continued checking and messing around it suddenly dropped back to 2500ish psi. Which is what it does with the functions as well, so it comes and goes without any rhyme or reason. It acts like it is lifting the main relief (which is new and not been messed with) way before its able to actually build the appropriate pressure or it's dumping it somewhere and this is where I have shifted my focus, but I am unable to determine where this can occur. The line reliefs are not lifting from operation, and this is an assumption because I am not seeing any drift in any functions after they are lifted like I have in the past. That brings me back to a new question, is there something that works in sequence with the main relief like a spool or something which can cause a bypass scenario or something like that?

 

[LACHAU]

Please see attached images below.

 

[LACHAU]

...Also, verified using a new gauge over the weekend and my pilot pressure is 500-600psi at full idle and at low idle 250ish psi.

You are probably mounting a hydraulic pressure gauge in place to measure the main pump control pressure.

 

[The Dirt Guy]

Thanks thats good information and thats the spot now that I see the fitting...the gauge is installed in the correct spot. The pilot function psi readings above are also accurate when I tested (they are very close to your sheet).

I also just got off the phone with John Deere and after speaking with them, their thoughts regarding the issue is pump controller. What's the likelihood of this? I'm kind of leaning that way too since all readings and tests appear to be accurate.

 

[Diesel Dave]

I think next steps would depend on how much load (hydraulic pump flow/ pressure ) is on the engine with normal operation versus when low hydraulic pressure issue is occurring.
I would think checking turbo boost pressure would be the easiest and most accurate way to confirm load. You will need to install a low pressure (15 or 30 psi) gauge at the air inlet on the cylinder head.
Full speed boom up and stick out (or high speed propel on relatively flat ground) would likely create close to 2500 psi with (2) pumps in use.
Check turbo boost under those conditions.
Check turbo boost pressure again when ever your low hydraulic pressure issue is occurring with the (2) pumps in use.
If the pump valve controller is suspected to be randomly destroking the hydraulic pumps and allowing only 2500 psi to build (along with low turbo boost pressure) then yes I agree with a bad pump valve controller. I also want to say a possible pump issue but I really can’t think what internally would cause both pumps to drop psi intermittently and at the same time.
If the low hydraulic pressure issue is the result of an internal leak or a valve dumping oil etc (along with high turbo boost pressure) then no it would not be a pump valve controller issue.

 

[LACHAU]

In case of speed sensor failure, MC will send wrong signal to torque control solenoid valve causing pump flow to be reduced to minimum==>machine pressure will be reduced.

 

[Vetech63]

The steak dinners are piling up!

 

[The Dirt Guy]

LACHAU, thanks for the schematics I will check resistance and functionality and follow up after the weekend or sooner if time allows. I do know the speed sensor is new and recheck resistance to spec. The proportional valve solenoid if it is the ones on the pilot filter manifold, they are good I have verified them as well this past weekend, but I can't remember what the manual actually calls them. The speed controller (throttle knob) I have not evaluated ever so that will be on the to do list along with the input & outputs of the pump controller MC. Also, this is good information and dialog. I strongly believe it will eventually be resolved.

Just a quick recap: Machine will randomly lose hydraulic speed/power (very slow and weak but will continue through each function) on all functions at same time the display pump pressures are at 17-19mpa, example when display is in diagnostic mode to monitor pump pressure 35.5mpa is the target, when using any function to verify the setting of 35.5mpa, while machine is proceeding through the pressure building stage it will stop at 17-19mpa and if you repeat the same function or use another function several times " hit or miss" it may decide to continue to build and achieve the desired 35.5mpa reading on pump 1 and 2 delivery pressure setting on display. This occurs cold or at operating temperature. All other display setting has met the specs per the technical manual. When performing the tests verified engine RPM at 2010 through all scenarios when machine is acting up and halfway running right, engine never lugs or slows down, note: I am aware engine rpm is low but has always been around 2010rpm.


These are the items which have been replaced and re-checked.
Hydraulic pump was tested by JD dealer and stated to be good.
Pilot pump pressures have been verified through two separate set of gauges and determined to be good.
Boom up pressure sensor new
Arm in pressure sensor new
Swing pressure sensor new
Pump 1 pressure sensor new
Pump 2 pressure sensor new
Crankshaft position sensor new
Engine Speed Sensor on hydraulic pump housing new
Engine Wiring Harness (only) new
Main Relief Valve (hydraulic) new
verified grounds are secure
verified all fuses are good
New batteries
verified no codes are present on display or pump controller
speed solenoid 11 new and 12 tested good photo below.

 

[The Dirt Guy]

I think next steps would depend on how much load (hydraulic pump flow/ pressure ) is on the engine with normal operation versus when low hydraulic pressure issue is occurring.
I would think checking turbo boost pressure would be the easiest and most accurate way to confirm load. You will need to install a low pressure (15 or 30 psi) gauge at the air inlet on the cylinder head.
Full speed boom up and stick out (or high speed propel on relatively flat ground) would likely create close to 2500 psi with (2) pumps in use.
Check turbo boost under those conditions.
Check turbo boost pressure again when ever your low hydraulic pressure issue is occurring with the (2) pumps in use.
If the pump valve controller is suspected to be randomly destroking the hydraulic pumps and allowing only 2500 psi to build (along with low turbo boost pressure) then yes I agree with a bad pump valve controller. I also want to say a possible pump issue but I really can’t think what internally would cause both pumps to drop psi intermittently and at the same time.
If the low hydraulic pressure issue is the result of an internal leak or a valve dumping oil etc (along with high turbo boost pressure) then no it would not be a pump valve controller issue.

The load (hydraulic pump flow / pressure) never meets the limit to pull the engine down at any point except for normal operation which is around 35.5mpa due to the inability of the pumps to function correctly. Verifying this can occur once the pumps are meeting the desired mpa. The engine remains at constant rpm throughout all operations it never drops rpm or lugs it operates as designed. I can check the boost but I'm doubtful of this being the culprit since its hit or miss and it really feels like it wants to build hydraulic pressure but as its building it stops (communication ecu) or bypasses (a valve) or something. It's really odd and random that is why I keep going to ecu communication issues. I will follow up after I look at it again this weekend or sooner.

Can you elaborate any on the following "internal leak or a valve dumping", which valve(s) are you referring to in your statement: If the low hydraulic pressure issue is the result of an internal leak or a valve dumping oil etc (along with high turbo boost pressure) then no it would not be a pump valve controller issue.[/QUOTE]

 

[mg2361]

engine never lugs or slows down

It is supposed to.

I think the engine rpm's need to be brought up to fast idle spec and a Hydraulic Pump Regulator test (engine pulldown) be done. Sounds to me like there is either an issue with the wiring and you are losing engine speed signal to the controller causing it to destroke the pump or something wonky is going on with the pump regulators. They might only need an adjustment. But, the engine speed needs to be at spec to do that. Since the speeds are not mechanically adjustable, you would have to figure out why the speed is low (bad throttle dial for example).

 

[Diesel Dave]

Dirt Guy , I was under the impression that good hydraulic performance (pressure and function speed) was the norm and the poor performance issue was not a near constant occurrence.
Under that same impression, I suggested to check the turbo boost pressure when hydraulic performance was good and also check it when performance was poor to get an indication to what extent the hydraulics were loading the engine in the 2 scenarios before you bolted on a $ 2500.00 non returnable pump valve controller as your Deere dealer was leaning towards.

 

[The Dirt Guy]

The steak dinners are piling up!

It's well worth more than a steak dinner to me at this point.

It is supposed to.

I think the engine rpm's need to be brought up to fast idle spec and a Hydraulic Pump Regulator test (engine pulldown) be done. Sounds to me like there is either an issue with the wiring and you are losing engine speed signal to the controller causing it to destroke the pump or something wonky is going on with the pump regulators. They might only need an adjustment. But, the engine speed needs to be at spec to do that. Since the speeds are not mechanically adjustable, you would have to figure out why the speed is low (bad throttle dial for example).

I agree engine rpm does need to come up but 2010 is within spec of providing accurate results by the book. The speed control knob is checking out as well by the book but I may replace it as well. This will require additional digging I will have to circle back to this and follow up but thanks for the input its all good stuff and in the right direction.