Replacing hydro pump--what else do to while there?

[Obi-Wan-YJ]

My XR4145 (manual tranny) is at the dealer today to diagnose low hydraulic power when hot. We suspect that they'll find that the hydraulic pump needs to be replaced. I don't know what labor is required to replace that pump, but, if they have to do that, are there any other upgrades or modifications that I should have them do while they're in there?

Are there higher-capacity pumps available? Should I have a 3rd line added for the front (for a grapple, etc)? Does the labor for adding a 3rd line overlap much with the labor for replacing the pump? Is there anything else I should be looking at in order to save labor costs down the road?

This is a 2016 model with about 220 hours on it. I've only owned it for 1.5 years (50 hours) and have not replaced any fluids during that time.

It's in the shop because although the loader or 3-pt can lift plenty of weight when cold, as soon as the hydraulics heat up, the lift capacity drops dramatically. After an hour running a 3pt tiller, it can no longer lift the tiller off the ground. The loader can carry a single 1-ton pallet down my driveway, but can't pick up the next pallet. Fluid's full & looks good. Filter is new. No visible leaks.

 

[oldnslo]

My very first question is if the pump has failed would be why at such low hours.

If at dealer they should clean the suction screen and inspect the suction hose if it has one for cracks or if getting soft. Should also replace hydraulic filter.

Adding 3rd function for grapple would be totally separate from replacing the pump.

 

[Obi-Wan-YJ]

I should mention that in the 18 months I've owned it, the 3-point always lifted slower than I thought it should. A few weeks ago, I replaced the original-to-me hydraulic filter with a new, LS-branded one. Now the 3-point lifts plenty fast. However, I still have the same loader performance described above. I wonder if the 210-hour filter was clogged due to the same problem that's causing the poor performance when hot.

I should also mention that I've never been able to make the loader joystick lift the arms and tilt the bucket at the same time, no matter how carefully I move the joystick. Should I be able to do that? Does that hint at this same problem?

 

[Eagle1]

I should mention that in the 18 months I've owned it, the 3-point always lifted slower than I thought it should. A few weeks ago, I replaced the original-to-me hydraulic filter with a new, LS-branded one. Now the 3-point lifts plenty fast. However, I still have the same loader performance described above. I wonder if the 210-hour filter was clogged due to the same problem that's causing the poor performance when hot.

I should also mention that I've never been able to make the loader joystick lift the arms and tilt the bucket at the same time, no matter how carefully I move the joystick. Should I be able to do that? Does that hint at this same problem?

At what RPM? hard do when below 1800.... more flow closer to PTO speed.

 

[oldnslo]

I suspect the filter you replaced was on the pump inlet since it changed operating speed. If that is true you were cavitating( starving pump of oil) which destroys pumps. That could explain your failing pump if my above presumption is correct.

 

[GS650GL]

The hydraulic pump and steering pump are located on the side of the engine so they are easy to change. There is nothing else related to the pump that would involve adding third function. You should do a 250 hour service and change the hydraulic oil as long as you are replacing the pump. It should have had a 50 hour service which involves changing the hydraulic filters after break-in. If the hitch raises faster now after changing the filter it means the old filter was getting restricted which could have lead to shortened pump life. Also, if one of the remote hydraulic levers is not in neutral (detented) or the hitch is not cancelling when raised all the way, it will deadhead the hydraulics and blow the relief valve constantly which can overheat the oil in a short time and also put more load on the pump. If a remote lever is not in neutral, usually the hitch will not raise at all. I have seen a few that the hitch did not cancel and was still trying to raise even though it was all the way up, which also deadheads the pump and can cause remotes and third function to not work. Steering will still work because it has it's own pump and relief valve but still uses the same oil. Check to make sure that when the hitch arms are all the way up, you can still lift them up a couple inches higher by hand to be sure the hitch is cancelling out.
Not being able to raise and tilt at the same time is totally unrelated and is a separate issue. It depends on the design of the loader valve. Some you can do both and some you can't. Some have parallel priority circuit and some have no priority, and some have better feathering spools to give better control. The joystick control cables need to be in good shape and adjusted correctly also.

 

[Obi-Wan-YJ]

You should do a 250 hour service and change the hydraulic oil as long as you are replacing the pump.

The service manual says that the hydraulic oil is a 500-hour replacement. I'm sure a good bit of it will necessarily get drained & replaced in the process of replacing the pump, though. If they want to replace it all, that's fine by me.

It should have had a 50 hour service which involves changing the hydraulic filters after break-in. If the hitch raises faster now after changing the filter it means the old filter was getting restricted which could have lead to shortened pump life.

I'd love to know what caused that initially. Maybe some crud got in through the fill hole? Maybe the wrong fluid was used at the 50-hour replacement? I bought this tractor from a dealer who bought it from an auction several states away, so I don't know whether the 50-hour service was performed by a dealer or the owner (or even at all).

Also, if one of the remote hydraulic levers is not in neutral (detented) or the hitch is not cancelling when raised all the way, it will deadhead the hydraulics and blow the relief valve constantly which can overheat the oil in a short time and also put more load on the pump. If a remote lever is not in neutral, usually the hitch will not raise at all. I have seen a few that the hitch did not cancel and was still trying to raise even though it was all the way up, which also deadheads the pump and can cause remotes and third function to not work.

There are no detents on either of my 3-point levers, and no mention in the owners manual of setting the green draft control lever to any particular setting if you're not using draft control. When I'm just driving around, the blue 3-point lever generally has the arms raised somewhere in the top half, but rarely pegged all the way up.

I'm not sure what you mean by "deadheading." Can you elaborate?

Not being able to raise and tilt at the same time is totally unrelated and is a separate issue. It depends on the design of the loader valve. Some you can do both and some you can't. Some have parallel priority circuit and some have no priority, and some have better feathering spools to give better control. The joystick control cables need to be in good shape and adjusted correctly also.

That's unfortunate. I hope I get lucky and that feature exists when I get my tractor back from the shop. It's a little annoying to have to stop raising my load at several points so that I can level it out.

 

[Obi-Wan-YJ]

OK, so I took my LS XR4145 to the nearest New Holland dealer for a few days. They tested the flow rate of the pump, which was at 6.4 gpm when cold and about 5.4 gpm when the fluid heated up. They declared that to be the cause of my problem and replaced the hydraulic pump for $2000. They measured the flow at a solid 6 gpm no matter the temp. They did not test the pressure, even when I asked them to.

I brought the tractor home yesterday and tried to move some more 1-ton pallets of bricks using my 400-lb forks (2400 lb total load). I have a 500-lb water tank hanging off the 3-pt for ballast. It lifted the first just fine (6" off the ground, transported 50 yards). It struggled to lift the second. It refused to lift the third off the ground. This is the same behavior I had before, with the old pump.

When I called them this morning, they (the service manager & the tech) tried to tell me that I was lifting too much weight. The loader is rated for 2700 lbs at full height (at the pin) and 3800 lbs of break-out force. The center of gravity of my load is about 24" in front of the loader pin. They claimed that the weight of the loader itself had to be subtracted from the rated load, which I'm sure is BS. They also said that the 3800-lb break-out rating only applied to digging, and not to lifting a loose load 6" off the ground, which I'm also not sure I believe.

If a loader is rated for X lbs, will it lift X+300 lbs for a short time when the fluid is cold, or will it simply refuse no matter what? How much difference should the fluid temp make for a properly functioning loader?

I'm taking the tractor back to them next week for them to inspect further. I did not yet confront them about why they performed a $2000 pump replacement if they thought this was normal behavior.

What do you experts think? They sound inept to me, but I'd like to get a better repair out of them since they already have $2000 of my money with no improvement in performance. This dealer is a regional chain with a good reputation (KanEquip). The next-closest dealer is an hour away and of unknown reputation.

 

[oldnslo]

Not lifting is flow loss - inability to build pressure. Next time you use the tractor or just do this as a simple non-invasive test.

With everything cold or at start up check temperature of pump housing vs pump inlet and outlet lines when lifting a load. Is pump housing getting significantly hotter than inlet or pressure line? Follow the outlet (pressure) line to the next component. Is anything there getting hot quickly compared to inlet? Follow line to next component. Again check for heat.

Flow escaping creates heat and if you have 6 GPM going somewhere it will get hot at that point.

It is something between pump and loader valve or possibly a component in loader valve itself.

 

[Obi-Wan-YJ]

@oldnslo Do this with a laser thermometer, I assume? I've always wanted an excuse to go buy one. Should I do this at idle speed, or does it matter?

The owner's manual says the hydraulic system is rated at 8.2 gpm. The dealer measured both the old & new pumps at just 6 gpm. Is this a difference in where the flow is measured? A 25% reduction in rated flow concerns me. They claim to have replaced the pump with a 12cc model, which I know is the proper size.

 

[GS650GL]

There are no detents on either of my 3-point levers, and no mention in the owners manual of setting the green draft control lever to any particular setting if you're not using draft control. When I'm just driving around, the blue 3-point lever generally has the arms raised somewhere in the top half, but rarely pegged all the way up.

I'm not sure what you mean by "deadheading." Can you elaborate?

To accurately diagnose a hydraulic issue you need to measure both flow and pressure, not just one or the other. A pump can put out enough flow under low or no pressure to make it look like it's OK, but when you start building pressure with the oil at operating temp, the flow should not drop by more than 10% at 1500 psi. Example: if a pump puts out 10 gpm at specified rpm under no pressure, it should not drop below 9 gpm at 1500 psi. If it drops more than 10%, the pump is worn and bypassing oil internally. How did they measure the flow? A diagnostic flowmeter has a load knob that can be turned to gradually build pressure so if they used one to check flow, they should have been able to check pressure also. If the knob is turned to the point where flow almost stops, thats's the relief valve opening pressure. I think your relief valve should be set to 2400 PSI. A bad or misadjusted relief valve is not affected by oil temp and the pressure will be always low. A restricted filter may cause the hydraulics to be slower, but will still have the same power (unless it's plugged and starving the pump, of course) A worn pump will work better when cold and lose pressure when hot, which sounds like the problem you are having. All loaders will slowly settle downward over time, but does it settle faster or worse when the oil is hot? If so, the boom cylinders could be bypassing oil internally.

There are no detents on either of my 3-point levers, and no mention in the owners manual of setting the green draft control lever to any particular setting if you're not using draft control. When I'm just driving around, the blue 3-point lever generally has the arms raised somewhere in the top half, but rarely pegged all the way up.

I'm not sure what you mean by "deadheading." Can you elaborate?

When I mentioned detents, I was referring to the rear remote control levers for the couplers on the back where you can plug in hydraulic hoses, not the 3 point hitch levers. Deadheading means the pump is at max pressure but the oil cant't flow anywhere which blows the relief valve which affects the performance of all functions, and overheats the oil. A remote lever not in neutral or the hitch at max height and not cancelling (still trying to raise) will cause it. If you lower the hitch all the way down, will it raise back up and cancel before it hits the upper limit? How hot is the oil getting? Inside the transmission it should not get hotter than 100 degrees F above ambient air temp. Make sure the oil cooler and radiator are not plugged with dirt. I hate to say it, but unfortunately, there's usually a reason someone sells at an auction to get rid of a machine several states away.

 

[oldnslo]

@oldnslo Do this with a laser thermometer, I assume? I've always wanted an excuse to go buy one. Should I do this at idle speed, or does it matter?

The owner's manual says the hydraulic system is rated at 8.2 gpm. The dealer measured both the old & new pumps at just 6 gpm. Is this a difference in where the flow is measured? A 25% reduction in rated flow concerns me. They claim to have replaced the pump with a 12cc model, which I know is the proper size.

A laser thermometer would be best but if components are accessible your hand would work.

Is the 8.2 GPM the combined flow of both steering and implement?
Example: 2.2 GPM is steering and 6 GPM is for implements.

 

[Obi-Wan-YJ]

A laser thermometer would be best but if components are accessible your hand would work.

Is the 8.2 GPM the combined flow of both steering and implement?
Example: 2.2 GPM is steering and 6 GPM is for implements.

The manual says 8.2 gpm for the pump and 4.1 gpm for the steering. The 6 gpm measured by the shop is somewhere in between, so I'm not sure where they measured it.

 

[oldnslo]

For reference:
A 12 cc pump spinning at 2600 RPM = 31.2 liters/min or 8.25 GPM at 100% efficient.

If only seeing 6 GPM I would be asking dealer the question where is the rest of the flow from that new pump?
Like GS650 asks it Would also be nice to know what flow does vs pressure since that is the real diagnosis for a failing pump with ALL other components removed from the system. I.e. flow meter is first thing from the pump to insure no flow loss through any other component before the flow meter.

I wish you the best in getting this problem resolved.

 

[GS650GL]

It's important that they measured the flow correctly or the numbers are misleading. Like oldnslo said, the flowmeter needs to be hooked directly to the pump outlet, not somewhere downstream, and the outlet of the flowmeter should go directly back to reservoir and not through any other plumbing because the return could have some restriction and back pressure that could affect the test results. But it's important to remember that with the flowmeter hooked directly to the pump, the relief valve is no longer in the circuit and if too much pressure is built by the flowmeter load control, the pump can split apart. I've seen it happen.

 

[Obi-Wan-YJ]

In case you all hadn't figured this out, I'm rather new to using a loader (18 months) and had never stressed its capacity until this month.

@GS650GL I double checked the rear levers. One is a momentary lever, which of course springs back to center. The other one was, indeed, pushed all the way to one end. That's how I got it back from the dealer, and may well have been how I gave it too them. I moved it back to the center detent and will be careful to keep an eye on it going forward.

So I went out today to see how many 1-ton pallets of bricks I could move before my tractor gave up. This time, I raised my engine rpm beyond the middling range up to about 2300 rpm. (PTO speed is 2400) To my surprise, I was able to move all 15 of the remaining pallets--9 of them one right after the other--and the tractor never complained. This was with the pallet pushed all the way back against the forks mount, the tips raised up as high as they would go (not very far), and the back of the pallet raised about 6" above ground. I moved them about 50 yards. I had one pallet that weighed 2500 lbs, and while I could roll the fork tips up, I could not raise that pallet off the ground without offloading some weight.

My loader is rated at 2713 lbs at the pin at full height and 3802 lbs breakout force. The pin is 67" from the main pivot at the back of the loader arms. The forks+bricks weigh a combined 2350 lbs with a center of gravity 26" beyond the pin, or 93" from the main loader arm pivot (40% farther out than the pin). A little math says that 2317 lbs at the pin equates to 1954 lbs at my load's center of gravity. This means I was able to comfortably lift 400 lbs more than the loader is specked for. The one heavier pallet (at a longer distance from the pivot) that I could not lift would have been about 1000 lbs beyond spec. Am I figuring that right when I assume that the lift capacity is reduced proportionally as the load moves farther out from the pin? If I'm calculating things correctly, then it appears that my loader is now operating just fine now that I'm learning more about how to run it.

I'm still a little fuzzy on how the 3800-lb breakout force differs from simply lifting something a couple inches off the ground. Is that an entirely different mechanical operation?

I'm very curious to see how much my 3-point can lift for a sustained time with the new pump. This spring, I borrowed a PTO tiller, and after an hour of use at PTO rpm (2400), I was unable to lift the tiller off the ground. I'm considering buying a 3-pt frame for my forks, since the 3-pt is rated for 2469 lbs at 24" behind the links.

I wish I could answer some questions about how the dealer did some of their testing. Alas, every single employee there that I spoke with has sounded... less than competent, so I think pursuing those answers is a lost cause. I will be buying a laser thermometer tomorrow and a hydraulic pressure gauge soon. My tractor does not have an OEM hydraulic fluid temperature gauge.

 

[Obi-Wan-YJ]

Upon further consideration, the geometry of the lift cylinders with respect to the loader arms also affects the lift capacity, so there's more to it than just the load's distance beyond the pin. The cylinder geometry has better leverage when the load is near the ground than when the load is at full height, and it's that full height capacity that is published. I could do that math, too, if I felt like it, but I don't at midnight. Suffice to say that I'm probably not exceeding the rated lift capacity like I suggested in my previous post.

 

[oldnslo]

Upon further consideration, the geometry of the lift cylinders with respect to the loader arms also affects the lift capacity, so there's more to it than just the load's distance beyond the pin. The cylinder geometry has better leverage when the load is near the ground than when the load is at full height, and it's that full height capacity that is published. I could do that math, too, if I felt like it, but I don't at midnight. Suffice to say that I'm probably not exceeding the rated lift capacity like I suggested in my previous post.

Sounds like problem is resolved. Since pressure is lifting force you might want to invest in a pressure gauge to verify what the system pressure - relief setting is. Then you will know if getting full rated lift capacity.

 

[Obi-Wan-YJ]

It's been a month, but I finally got around to doing the tests that you all recommended earlier.

While lifting about 1800 lbs of bricks with the loader, using a laser thermometer, I couldn't find any lines or components that were a noticeably different temperature than any other.

I made myself a pressure tester (after one false start with the wrong style of quick connect--my LS XR4145 uses 7241-A) and put it on the "bucket curl down" line. The pressure maxes out at 2400 psi, which is right where spec says it should be. As soon as I release the joystick, the pressure drops. Within a few seconds, it's down to 2200 psi. Within a minute, it's down to 1200 psi. No sign of leaks that I could see. Is this pressure drop normal?

 

[GS650GL]

Yes, the pressure will normally bleed off slowly.