JD4520 Steering trouble when bucket is full.

[charosenz]

I have a 2007 JD 4520. I have started to notice that I have difficulty steering to the right when the bucket is full of heavy dirt. I turn the wheel to the right but the tires do not turn to the right like they should. They barely turn (angle) to the right. It seems worse when I am going downhill. I have noticed it gets better when I increase RPM above 2600 but of course I know something is not right. Esp since it turns to the left just fine. The transmission is properly filled with Low Vis HyGard. The bucket lifts smoothly and so does the 3 point....

Any idea what is happening?

CR

 

[Wagtail]

So the steering is normal without a heavy load in the bucket?

If so then the difference is the load in the bucket... too heavy and/or unbalanced.

How much counterbalance weight is on the 3PL?

 

[CH4Ohio]

I'm sure you've checked, but have to ask . . .

You said the transmission is full. Did you check the power steering reservoir? It's a separate system. Did you check your fan belt to be sure it's in good shape and tight since it turns your power steering pump??

 

[charosenz]

So the steering is normal without a heavy load in the bucket?

If so then the difference is the load in the bucket... too heavy and/or unbalanced.

How much counterbalance weight is on the 3PL?

I appreciate your comments. I have a 7ft wide box blade. I believe it is about 760lbs. In regards to it being too much weight.l...I have to note that the odd issue only started recently, so I wonder if it is really too much weight and esp since it does not happen while turning left - only turning to the right....

 

[charosenz]

I'm sure you've checked, but have to ask . . .

You said the transmission is full. Did you check the power steering reservoir? It's a separate system. Did you check your fan belt to be sure it's in good shape and tight since it turns your power steering pump??

No. I read the manual and there is no mention of a separate power steering system reservoir. But I sure will look for one!!!! I should have thought of that!!! Also I do not note any belt noise but I sure will check it.

 

[CH4Ohio]

No. I read the manual and there is no mention of a separate power steering system reservoir. But I sure will look for one!!!! I should have thought of that!!! Also I do not note any belt noise but I sure will check it.

I could be wrong, and if so, someone on here will let us know pretty quick. But I think it's got a separate power steering pump and reservoir. That may not be the problem, but it's interesting that you can turn left but not right.

It may be that you've just got too much weight on the tires, but that should make your steering difficult, not inoperative.

Good luck with it.

 

[CH4Ohio]

I looked at the parts diagram and I don't see a separate power steering pump either . . .

Will be interesting to hear from some of the experts.

A quick look under the hood will, of course, confirm that you do or don't have a power steering pump.

 

[zzvyb6]

Put some more air in the steered tires. If they are Turf (R3) switch to R4's (loader tires with stiff sidewalls). You should expect a difference in assist force in one direction because the boost cylinder has a rod in it and thus cuts down the area that the hydraulic pressure acts on. If your front tires are in a wide track position, turn them around to narrow your front track (watch for rotation direction arrows that might be on the sidewall).

 

[charosenz]

I looked at the parts diagram and I don't see a separate power steering pump either . . .

Will be interesting to hear from some of the experts.

A quick look under the hood will, of course, confirm that you do or don't have a power steering pump.

Ill be looking first thing in the AM....

 

[charosenz]

Well I looked under the hood this morning. There is no steering pump on the fan belt. Only the Alternator and the Water pump. I traced the steering cylinder hoses back to where they disappear in behind the engine j- basically behind where the circuit breaker panel is. There must be some sort of control valve back there that somehow connects to the steering wheel shaft/linkage? I am guessing it is somehow integrated with the hydraulic/transmission oil??? But it must be a real pain to get to it. ugh! I can only suspect that somehow the hose that pressurizes the line that causes the steering cylinder to move the wheels to the right must be restricted.....

 

[beenthere]

What has been the hyd oil and filter (also screen) maintenance?

If okay there, maybe the power steering control valve.

Some oil pressure checks may be in order to track this down.

Might be in the hyd. steering cylinder.

 

[charosenz]

What has been the hyd oil and filter (also screen) maintenance?

If okay there, maybe the power steering control valve.

Some oil pressure checks may be in order to track this down.

Might be in the hyd. steering cylinder.

The oil and filter were changed 300 hours ago...so I will be doing that. But the "right" vs "left" has me baffled... Dealer wants over $1800 for new steering control unit. So Im hoping it wont be that...

 

[beenthere]

This is the compact utility 4520, and has this filter strainer..

Think given the right vs left difference, I'd want to know what the oil pressure is at that steering cylinder. Not overly expensive to check that out, but time consuming.

 

[charosenz]

Update: I stopped in the JD dealer and talked with the guys at the service desk. They said it is not likely it is the Trans filter if the rest of the hydraulic system is operating correctly as it is all the same system.

They said the two most likely culprits are:

1) The Steering Control Unit is bad or plugged etc.
2) Possibly the Steering Cylinder is bad.

They advised an easy way to check on the steering cyl is to extend or retract the cylinder (Wheels off the ground) and remove the corresponding line to check and see if there is any oil bypassing the internal seals. If so that may be the cause. (after thinking about this - while I wish this was the cause - I would think if the internal cyl seals were bad, that it would be evident when turning both directions not just to the right?)

It would be great to put a gauge on both lines to the steering cyl lines too. I wonder what amount of pressure ga I would have to buy?

 

[beenthere]

Per tractor data, looks like 2500 psi for the hydraulics. Mine to 5000

TractorData.com John Deere 4520 tractor information

www.tractordata.com

Up to 3000 psi on Amazon for $11

 

[charosenz]

Thanks, I was pretty sure that would do it, just ordered one. It is a good idea to check that steering cylinder and the pressure to it before making the big decision to have a JD dealer replace the Steering Control Unit. That $1800 cost is a big dent in my wallet....

 

[charosenz]

I got my gauge today. I hope to test those lines to the steering cyl soon. Might be a week or so though. Ill post the results here after testing.

 

[arlen4720]

There is a filter on the pressure side of the power steering system. It is in your manual. It’s right along the frame on the left side. When that is plugged, it will cause this issue.

 

[RoyJackson]

Put some more air in the steered tires. If they are Turf (R3) switch to R4's (loader tires with stiff sidewalls). You should expect a difference in assist force in one direction because the boost cylinder has a rod in it and thus cuts down the area that the hydraulic pressure acts on. If your front tires are in a wide track position, turn them around to narrow your front track (watch for rotation direction arrows that might be on the sidewall).

This!!
First thing to check is the front tires' air pressure. And, you probably find that with loader use, the air pressure should be increased (that might be in your tractor's manual...or your loader manual

 

[oldtimer 66]

I have a 4320 Cab /2006 and the power steering filter is on the left side of the tractor under the cab floor. It about 3 to 4 inches long, hex shaped and it takes a couple of large wrenches to remove. Remove it from the tractor and then you need to disassemble the filter to remove the mess screen and clean it. Mine will only go on one way due to the connectors. After you clean yours just make sure you have it going the correct direction/ in/ out/ etc. Later.