JD 5205 Steering Slip

[blehmann]

Scratching my head trying to figure out whether to have the hydraulic cylinder rebuilt or pull the steering control valve and rebuild it first. The tractor pulls a little to the right and it takes a constant slight turn of the steering wheel to the left to keep it going straight. No external leaks but apparently a seal in the cylinder is leaking or an o-ring in the control valve is boogered up and letting oil go to the wrong side. This only happens until the oil gets warm. Has anyone had this issue and what fixed it? Neither one is terribly expensive to rebuild, but I sure would like to figure out which part to work on.

 

[blehmann]

I am rather dense at times. I think that I have it figured out. I was working on the assumption that air was getting into the steering cylinder because I could turn the wheels to the stops and hold for a few seconds and the problem would go away for awhile. I did this for about the last year then I found a rather loose hose fitting about a month ago. Even though it wasn't leaking, I was thinking that maybe it was pulling a vacuum when the oil in the cylinder cooled and was drawing air in through the loose fitting. The fitting has been tightened and the problem is still there. Upon rethinking the issue, the cylinder shouldn't move if the steering control valve is in a neutral position. The only way that a cylinder can move is if there is unequal pressure on one side and also a place for the oil on the opposite side to move to. While I don't yet know the inner workings of the control valve and exactly what is happening, the problem has to be in the control valve.

 

[K5lwq]

I believe that your tractor has a double rod cylinder meaning the rod comes out both ends of the cylinder. If this is correct it could be the piston seal. Oil can bypass in the cylinder allowing the wheels to turn.

It still could be the valve but the cylinder could be the problem as well. You would need to isolate the cylinder from the valve, cap the ends and see if the cylinder moves. If it does it is the seal in the cylinder.

 

[SPYDERLK]

Scratching my head trying to figure out whether to have the hydraulic cylinder rebuilt or pull the steering control valve and rebuild it first. The tractor pulls a little to the right and it takes a constant slight turn of the steering wheel to the left to keep it going straight. No external leaks but apparently a seal in the cylinder is leaking or an o-ring in the control valve is boogered up and letting oil go to the wrong side. This only happens until the oil gets warm. Has anyone had this issue and what fixed it? Neither one is terribly expensive to rebuild, but I sure would like to figure out which part to work on.

Hydrostatic steering drifts. The concern is why your tractor pulls to the right preferentially.

 

[zzvyb6]

First of all, there will ALWAYS be a tendency to steer off in one direction because a cylinder has unequal areas due to the rod. Next, It might be a rear problem. Check your tire pressures and wear state. Look for a dragging brake. Plus you can compensate for the pull by adding air to one rear or lowering its tire pressure. Next, in the front, check pressures and rim & spider positions if equipped. Add or lower pressure in one tire to straighten it out. Front wheel camber will affect a lead or pull. It still might be the steering column parts, probably a seal in the valve body.

 

[blehmann]

Interesting suggestions and I will consider them all. Thank you all for your thoughts. It does seem to me that if it were a camber or tire pressure problem, I could hold the steering wheel slightly to the left to compensate for the drift. What is actually happening is that I am having to do a slow turn to keep the tractor moving in a straight line. The steering wheel is making a complete rotation every fifty or sixty yards when cold. As the oil heats up, the tractor will travel straight for an increasingly further distance per rotation of the steering wheel. This pretty much eliminates tire pressure or camber as the culprit. The cylinder is a typical double acting hydraulic cylinder with the single rod connected to the left wheel and the base pinned near the center of the tractor. There is a connecting rod between the two wheels. I may try the capping of the cylinder when I am able to pick up some pipe plugs and caps. I'll have to do some measuring to see what size the cylinder fittings are. I certainly hope that they aren't some European thread.

 

[RickB]

First of all, there will ALWAYS be a tendency to steer off in one direction because a cylinder has unequal areas due to the rod.

Not so fast. Many steering cylinders are designed with equal volumes on both sides of the piston. Other tractors use dual steering cylinders which displace equal volumes of oil on both left and right turns.

 

[SPYDERLK]

First of all, there will ALWAYS be a tendency to steer off in one direction because a cylinder has unequal areas due to the rod. Next, It might be a rear problem. Check your tire pressures and wear state. Look for a dragging brake. Plus you can compensate for the pull by adding air to one rear or lowering its tire pressure. Next, in the front, check pressures and rim & spider positions if equipped. Add or lower pressure in one tire to straighten it out. Front wheel camber will affect a lead or pull. It still might be the steering column parts, probably a seal in the valve body.

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Not so fast. Many steering cylinders are designed with equal volumes on both sides of the piston. Other tractors use dual steering cylinders which displace equal volumes of oil on both left and right turns.

Yes, not always, and not on my Mahindra. It has unequal areas as described. -- Yet it does not exhibit a tendency to go one way or other when cruising. It is able, of course, to steer a little more strongly from the large/piston side. OP should be looking for another cause. Drift to the right should be explored as a road camber issue.

 

[blehmann]

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Yes, not always, and not on my Mahindra. It has unequal areas as described. -- Yet it does not exhibit a tendency to go one way or other when cruising. It is able, of course, to steer a little more strongly from the large/piston side. OP should be looking for another cause. Drift to the right should be explored as a road camber issue.

The only adjustment that I can make on this tractor is toe in or out. Camber and castor are fixed. I can see where you would say that it could be a road camber issue. This tractor is seldom driven on a crowned road, though. I first recognized the problem on level ground. Tire pressures are equal, toe in is within spec at 1/8".

I did think of a test that I can run to be certain that it is the steering control valve. I can reverse the two hoses and see if it starts pulling to the left.

 

[SPYDERLK]

Reversed steering. Go slow.