6500 4wd steering issue - drifting right

[farmbacker]

Thanks everyone for chiming in. Seems like there's a range of what's normal.

When I drive my purchased new 3016 about a half mile down the road, I have counted me having to completely turn the wheel , a little bit at a time, about two full revolutions over that distance..

I've got a nice stretch of flat road, so I'll drive straddling the crown and see what happens. I'm thinking I would need to turn the wheel several dozen times to go that distance, but I will check today and post back.

 

[farmbacker]

So I did some more testing. Going down the road, on the right side, it takes about a full revolution of the steering wheel every 50 feet or so to stay out of the ditch. Driving on the left side of the road, the tractor will come up and over the crown and still head for the ditch on the right, albeit more slowly. From what folks have said here, that seems like outside the normal range of adjustment that should be necessary. In fact, it makes driving in gears 7 and 8 a little too exciting for my taste.

Repair manual arriving tomorrow, hopefully it has some guidance on troubleshooting the steering. I emailed a Mahindra dealer, and he said there could be an issue with the centering spring in the HSU if someone took it apart previously and the spring came out of position. He said to remove both hydraulic hoses from the steering cylinder and that no oil should come out if the steering wheel isn't turned. Also, a mechanic friend said he had seen a similar issue on a different tractor, and it turned out that the cylinder itself was bypassing internally. Any idea how to test the cylinder itself?

I hope to have some time this weekend to mess with it, and I'll report back. In the meantime, any further insight is appreciated.

 

[SPYDERLK]

Have you checked tire pressure, alignment, etc. Are the front tires the same. Any fluid in them? Are the rears the same?, filled? - both, same fluid?... To me it sounds like you have a rolling bias causing a steady pull to the right.

 

[dickfoster]

So I did some more testing. Going down the road, on the right side, it takes about a full revolution of the steering wheel every 50 feet or so to stay out of the ditch. Driving on the left side of the road, the tractor will come up and over the crown and still head for the ditch on the right, albeit more slowly. From what folks have said here, that seems like outside the normal range of adjustment that should be necessary. In fact, it makes driving in gears 7 and 8 a little too exciting for my taste.

Repair manual arriving tomorrow, hopefully it has some guidance on troubleshooting the steering. I emailed a Mahindra dealer, and he said there could be an issue with the centering spring in the HSU if someone took it apart previously and the spring came out of position. He said to remove both hydraulic hoses from the steering cylinder and that no oil should come out if the steering wheel isn't turned. Also, a mechanic friend said he had seen a similar issue on a different tractor, and it turned out that the cylinder itself was bypassing internally. Any idea how to test the cylinder itself?

I hope to have some time this weekend to mess with it, and I'll report back. In the meantime, any further insight is appreciated.

To test a cylinder all you have to do is remove it or disconnect one end. Then either plug the ports or ensure there is no fluid flow external to the cylinder and try to push the rod. If the rod can be pushed by hand then the seals are allowing fluid to bypass the piston and need to be replaced. If you can't move the rod and the cylinder is full of fluid then it's something else like a bad orbital valve. Kinda like checking a bad shock absorber but more so.

 

[CADplans]

How about jacking up the front end (easy with a loader on!! :thumbsup

Then just start the tractor,,
If the tires move to one side or the other,,, on their own,,
the problem is the steering valve.

A defective cylinder seal would not cause movement in this test.

That valve is a very common issue on garden tractors with power steering.
I would think this tractor has the same type steering valve.

 

[farmbacker]

Have you checked tire pressure, alignment, etc. Are the front tires the same. Any fluid in them? Are the rears the same?, filled? - both, same fluid?... To me it sounds like you have a rolling bias causing a steady pull to the right.

So I took a good look at the front tires, and I had failed to notice that one has a more aggressive ag tread than the other. Presumably this could at least partially cause the issue. Also, both rear tires are loaded, but one seems nearly 100% full while the other is about 80%. I understand that all of these things could possibly make for steering issues, but I suspect there is still something going on with the power steering system itself. Seems like it may not be worth going nuts over it, at least not until I get front tires that match.

To test a cylinder all you have to do is remove it or disconnect one end. Then either plug the ports or ensure there is no fluid flow external to the cylinder and try to push the rod. If the rod can be pushed by hand then the seals are allowing fluid to bypass the piston and need to be replaced. If you can't move the rod and the cylinder is full of fluid then it's something else like a bad orbital valve. Kinda like checking a bad shock absorber but more so.

Haven't had time to remove the cylinder, but thanks for the advice, this seems like a simple test and makes sense to me.

How about jacking up the front end (easy with a loader on!! :thumbsup

Then just start the tractor,,
If the tires move to one side or the other,,, on their own,,
the problem is the steering valve.

A defective cylinder seal would not cause movement in this test.

That valve is a very common issue on garden tractors with power steering.
I would think this tractor has the same type steering valve.

I did do this - as you said, easy with the loader on! The wheels don't move from center on their own. However, if I steer all the way to the left (cylinder retracted fully) and let go of the wheel, the front tires will move back towards center a bit, maybe a few inches of steering piston movement. There is no movement if I do the same in the other direction. I did also notice that I can easily steer the wheels to the right just by pushing on the tire (i.e. standing next to the tractor). Much harder to turn the wheels to the left.

Not to hijack my own thread, but I will probably be ignoring this issue for the time being. Once I got the owner's manuals and started going over the tractor more closely, I discovered some really ugly stuff. Turns out the seller lied to me outright about the condition of the machine and went to some effort to disguise serious issue. Pretty quickly, I realized the hour meter wasn't working. Then I saw that the tranny, which I thought was a bit low on oil, was empty. I filled it up, and within a couple of days, oil started coming out of clutch housing. Removed clutch inspection hole cover and a few gallons of tranny oil dumped out. The inspection cover, including the weep hole, was sealed with RTV silicone. Then just yesterday I discovered that the oil pressure sensor was removed and replaced with a plug, wire disconnected and tucked up under dash. I guess an open circuit registers as high oil pressure on the gauge - I sure wish they made it the other way around. I'm off to grab a oil pressure tester - hopefully pressure is OK, and somebody was just too lazy to replace a leaking sensor. But at this point, I expect the worst.

Anyway, clearly some carelessness on my part, but also some outright deceit on the seller's part. Live and learn. For what I paid for it, it will be worth it to fix the tranny leak, but I'm not so sure about low engine oil pressure.

OK, thanks again for your help.

 

[dickfoster]

So I took a good look at the front tires, and I had failed to notice that one has a more aggressive ag tread than the other. Presumably this could at least partially cause the issue. Also, both rear tires are loaded, but one seems nearly 100% full while the other is about 80%. I understand that all of these things could possibly make for steering issues, but I suspect there is still something going on with the power steering system itself. Seems like it may not be worth going nuts over it, at least not until I get front tires that match.



Haven't had time to remove the cylinder, but thanks for the advice, this seems like a simple test and makes sense to me.



I did do this - as you said, easy with the loader on! The wheels don't move from center on their own. However, if I steer all the way to the left (cylinder retracted fully) and let go of the wheel, the front tires will move back towards center a bit, maybe a few inches of steering piston movement. There is no movement if I do the same in the other direction. I did also notice that I can easily steer the wheels to the right just by pushing on the tire (i.e. standing next to the tractor). Much harder to turn the wheels to the left.

Not to hijack my own thread, but I will probably be ignoring this issue for the time being. Once I got the owner's manuals and started going over the tractor more closely, I discovered some really ugly stuff. Turns out the seller lied to me outright about the condition of the machine and went to some effort to disguise serious issue. Pretty quickly, I realized the hour meter wasn't working. Then I saw that the tranny, which I thought was a bit low on oil, was empty. I filled it up, and within a couple of days, oil started coming out of clutch housing. Removed clutch inspection hole cover and a few gallons of tranny oil dumped out. The inspection cover, including the weep hole, was sealed with RTV silicone. Then just yesterday I discovered that the oil pressure sensor was removed and replaced with a plug, wire disconnected and tucked up under dash. I guess an open circuit registers as high oil pressure on the gauge - I sure wish they made it the other way around. I'm off to grab a oil pressure tester - hopefully pressure is OK, and somebody was just too lazy to replace a leaking sensor. But at this point, I expect the worst.

Anyway, clearly some carelessness on my part, but also some outright deceit on the seller's part. Live and learn. For what I paid for it, it will be worth it to fix the tranny leak, but I'm not so sure about low engine oil pressure.

OK, thanks again for your help.

I've had tires on a car make the steering pull. We had a set of Yokohama's on my wife's Subi and it started to pull left when we put the tires on. Took it back and had them align it but it was never quite right. We had it aligned several times after but with no real help. Finally after we changed the tires everything was cured as if by magic. I don't know what it was about those tires but obviously at least one of them wasn't put together right and it somehow caused the steering to pull to the left. If your front tires are different then that could indeed be your problem. How did you end up with different tires on the front? Hopefully it didn't come to you new like that.

 

[farmbacker]

I've had tires on a car make the steering pull. We had a set of Yokohama's on my wife's Subi and it started to pull left when we put the tires on. Took it back and had them align it but it was never quite right. We had it aligned several times after but with no real help. Finally after we changed the tires everything was cured as if by magic. I don't know what it was about those tires but obviously at least one of them wasn't put together right and it somehow caused the steering to pull to the left. If your front tires are different then that could indeed be your problem. How did you end up with different tires on the front? Hopefully it didn't come to you new like that.

Just bought this tractor, and it's very used - a little more used than I realized (hour meter not working). The tires are nominally the same size, but I just measured and one is about an inch larger in diameter than the other, not to mention the different tread. The ease of turning the wheels by hand in one direction does seem to me a steering hydraulics issue, but clearly I could fill a book with things I don't know. Once we get the leaking tranny squared away, I'll probably go ahead and replace the cylinder seals seeing how it's easy to get at and not terribly expensive for the seal kit.

One bit of good news - the engine oil pressure seems fine. I put a dial gauge on it and it was idling around 50 - 60 psi. Some previous owner must have been too cheap to replace a leaky sensor and just plugged it instead.

 

[dickfoster]

Just bought this tractor, and it's very used - a little more used than I realized (hour meter not working). The tires are nominally the same size, but I just measured and one is about an inch larger in diameter than the other, not to mention the different tread. The ease of turning the wheels by hand in one direction does seem to me a steering hydraulics issue, but clearly I could fill a book with things I don't know. Once we get the leaking tranny squared away, I'll probably go ahead and replace the cylinder seals seeing how it's easy to get at and not terribly expensive for the seal kit.

One bit of good news - the engine oil pressure seems fine. I put a dial gauge on it and it was idling around 50 - 60 psi. Some previous owner must have been too cheap to replace a leaky sensor and just plugged it instead.

Yep I think you've found your problem. I thought you'd checked the tires at the beginning. Take care of the tire thing before you go messing with the steering because I think the tire mismatch is what's causing your steering pull. It sounds like you have a number of problems that need fixin.