Power steering loosing power

[del]

Nailerguy </font><font color="blue" class="small">( My Dad used to tell me to carefully rule
out the obvious and whatever was left is usually the answer,
this has served me well over the past 43 years and while
I could be wrong here, I also could be right)</font>

Good info.

I received the same advice from my Pop, worded a little
differently, something like, "When you rule out all the
things that you think are possible solutions, what is
left is the impossible!"

In this case since most of the owners manuals and dealers
seem to recommend the low viscosity option, shouldn't
the pump work with either fluid just as well?

/forums/images/graemlins/smile.gif<font color="blue">D</font><font color="orange">E</font> <font color="green">L</font>/forums/images/graemlins/smile.gif

 

[JClark]

Considering the way JD is playing "gotcha" on the ballast and tires, I am glad I used the exact oil specified in the manual, right off the dealer's shelf. John Deere Low Viscosity HY-GARD (JDM J20D). I would really be screwed if I tried something else. I will note that the new oil is a different color than the old. The senior mechanic also noticed it but said it is not unusual.

 

[bigpete]

JClark, I understand that the hydraulic oil used out of the factory is red so as to allow for quick ID of any leaks. The recommended JD low-vis off the shelf, in the jug, is more of an amber color.

 

[JClark]

Bigpete,

Thanks, that makes sense. The low-vis oil I put in is amber.

 

[nailerguy]

Hey Del,
you are correct in that both oils are suitable for the pump and neither one will hurt anything in the hydraulic steering system. The low vis oil is much better for a colder climate as the steering will be quick and responsive on startup where as the high vis oil will need a heating cycle before it will offer the same type of response.

What I'm thinking here is that the steering on DCLARK's tractor was on the border line of working or stalling under a load before he changed the oil. If he lost as little as 50 to 100 psi by using the thinner oil, this could translate into several 100 psi /forums/images/graemlins/shocked.gif of lost steering effort depending on the actual pump pressure and the bore size of the steering cylinder, you know the extra straw that broke the camels back kinda thing in reverse./forums/images/graemlins/crazy.gif In fact, if anyone knows those spec's I can calculate exactly how much the loss could be.

One thing that is for sure though, I'm going to keep an eye on this thread until the answer is revealed or DCLARK gets his new tractor /forums/images/graemlins/grin.gif if Deere actually lets it go that far.

Nailerguy

 

[del]

I can't believe it has been 2 1/2 months since he took it in.

Pretty soon the dealer will have "owned" it longer then he has!

/forums/images/graemlins/frown.gif<font color="blue">D</font><font color="orange">E</font> <font color="green">L</font>/forums/images/graemlins/frown.gif

 

[JClark]

Nailerguy,

Your theory makes some sense. I'm going to a little research on hydraulic oil.

 

[jrlichina]

The problem is not the type of oil you are using. You have a NEW tractor. If your tractor had a ton of hours on it then it may be a factor. But the problem happened after you did a fluid/filter change. There could be something that got into the system and is blocking the priority valve or is in the steering valve, etc., this is not an uncommon event. JD should fix this problem without any question. Its a NEW tractor! Raise more hell. A tractor that has a dedicated power steering pump should not have steering problems!!!! Heck just look at their web site and that's what they boast about their tractor. Keep on them.

 

[JerryT]

I may have to retract my previous response to this, where I thought the problem had to be hydraulic. I was at the farm this weekend and got out my 4000 Technical Manual. The trouble shooting chart has several "problems" that may relate. The first is "steers hard left,right or both" Since this is a new tractor I am leaving out all the "worn parts" causes; that leaves
1. Toe-in incorrect
2. Tire out of round, size incorrect, or air pressure incorrect
3. Tie rod bent or damaged
4. Steering control unit (SCU) leaking internally
5. Steering cylinder leaking internally
The second problem is "steering locks in hard left or right turns". Causes are; 3. above.

I am somewhat surprised that wheel size is mentioned in the first problem because I can see how and abnormal front to back wheel differential could (in 4wd) cause other problems, but I can imagine how it could affect steering. Some of the other causes listed had to do with lubrication, any chance that the dealer and/or factory failed to lubricate the tractor before delivery? Hope this helps.

 

[DennoAce]

/forums/images/graemlins/shocked.gif

- I am very soon thinking of buying a new 4110gear with 410 loader and weight box for about $13k so this interests me greatly.

- JClark, I am absolutely in awe of putting up with what you have after spending $12+ grand (I assume) on this machine. I cannot imagine being as patient as you have been re: this issue. I cannot comprehend the total BS you have been given by the dealer, etc.

- I am dumbfounded why you have not taken it to another dealer, or why the dealer has not done certain fundemental things to try and figure this out such as swapping parts from another tractor (steering cylinder for example) to test. This would take little time. There are only a few parts that make this system work, and although I do not own one (yet /forums/images/graemlins/smile.gif ) , I have been around. The rotator/servo, the pump, the relief valve, , the lines and the cylinder and moving parts (tie rod,etc). Also an earlier suggestion of trying another machine which must surely be available with similar setup to show them it is not normal. I say again I do not own one yet but I KNOW that turning the wheel with reasonable effort, even with some low tire pressure and a reasonably loaded bucket without ANY ballast on hard ground must be possible! If it is not, than I WILL NOT buy a John Deere. This is BS.

- The viscocity of the oil in the case of this new tractor between two approved oils will not make any noticable difference whatsoever. If it does, something is seriously wrong.

- It seems to me the best bet to try first (although I could be wrong from this distance and there are other things it could be) is that you have air in the system. Personally I would drain and refill the oil again with filter first and then try to get the air out if there is any. Just moving the wheel back and forth under load could but not necissarily do this. There are other ways to do this and you could even try it under power, but this is what I would try:

-- With tractor off, relieve all pressure on system by moving all valves in every direction, steering wheel, etc...
-- Jack up the front axle (not with the loader)
-- Turn the wheels to the stops one way by hand (pushing the tires not using the wheel)
-- Crack the opposite fitting on the steering cylinder (if the cylinder is all the way out the one on the other side) so that oil drips out at a good clip
-- Turn the wheels slowly to the other stop by hand, noting any air coming out with the oil which will no doubt spray some.
-- Tighten the fitting making sure the wheels do not turn back a little by themselves thus drawing air into the cylinder again
-- Loosen the other fitting and do the same thing
-- I would do this procedure 2-3 times in a row.
-- Top off fluids, double check fittings are tight (no need to go crazy with hydraulic fittings), clean up mess, start the tractor and try it out.
-- Not saying this is the answer and I am not a JD tech just saying what I would do, without having put my hands on your rig (though I am dying to see this for myself)


- ps I thought I read something here about this so I just thought to mention that 4wd ratios should always be exactly the same or slightly higher in the front to prevent bind-up and stress on the driveline. Off-road is less of a concern than pavement, but I still would not do it for long (different front-rear ratios ala bigger/smaller tires). Yes some difference is technically OK (a small percentage in difference), but again why stress the components if you dont have to?

- I would be interested while I am here JClark (others?) as to your impression of tractor other than this, and if it a gear or hydro? I am planning on buying one soon and would love to hear feedback! /forums/images/graemlins/smile.gif