706 STEERING

[TimWafer]

The steering on my 706 has been very stiff since I got it a couple years ago. So far I have completely changed the fluid and installed new filters. I have overfilled the tranny by more than 5 gallons as well. The only thing i really notice is that the steering is stiff. The fasthitch seems to work fine. The rear remotes work fine. The PTO seems to work OK and the TA seems to be OK as well. You can steer it but its a workout. When you hit the limit of the steering in either direction you hear a squeal like a relief valve. I think that's normal.
From what Ive read it sounds like it could be a multitude of things. Given the symptoms I just mentioned is there a likely problem to address first?

 

[Roger Tomfohrde]

Jack the front end up and try it again. There maybe something binding.

 

[Janicholson]

If Rogers answer does not work, it could be the priority valving in the Regulator. Jim

 

[Donald in MN]

have you tried greasing the steering shaft under the bolster

 

[caterpillar guy]

when was the last time the front axle was greased or had good thrust bearings on the bottom of the knees? What are the spindle bushings like? With all these to check it could be any of those plus hydraulic possibilities too. I would start with the front axle parts first then move on to the hydraulics. Most of the hydraulics will take a pressure gauge and flow rater to test.

 

[Mrfred54]

If you find nothing wrong with the axle there are a couple of suspect orings that can blow out. One is between the transmission casting and the MCV. The other is between the MCV and the separator plate of the MCV.

 

[TimWafer]

I had to change the wheel spacing shortly after getting it and ended up removing the front axle in order to free up the telescoping tube. The spindles and everything seemed to move very freely. I can lift the front up with the forklift and try it again however.
To me it just feels more like a hydraulic issue. My 656 I can steer easily with one hand or even a couple fingers and spin the wheel around rapidly if need be. The 706 has constant resistance to the wheel turning in both directions. You really needs both hands to turn the wheel. No way you can spin it fast. It seems the faster you try to turn it the harder it is to turn. Its like something is severely restricting the hydraulic flow. However the TA and brakes seem to be working fine along with the fasthitch lift and rear remotes.
Ive ordered a manual for it. Ive never messed with the MCV valve as yet. Im currently trying to plow some food plots and turning around quickly at the ends of the rows is killing my shoulders.

 

[the tractor vet]

Well here myself i would be looking into the M C V , first with a pressure tet and then onto a flow rate . ya may have restricted flow thru the steering orface , thats the little plug on the back side of the MCV and Like Fred said it could be a blowen O/Ring but that usually shows up on the teltale light in the dash if yours works . And since more then likely your not in my rheum of travel area i can't just run over and check it out . On a 706 ya want around 230-245 psi AT OPERATING OIL TEMP . but YA NEED THE FITTINGS TO PU A GAUGE ON IT And More fittings to run a flow rater on it. Ya have a 9 GPM pump on the M C V on the back side to the valve body . 706and UP have a total of 3 hyd pumps . One for the M C V and one in the rear frame down on the left for the hitch and remotes and that one is a 12 GPM pump and ya got a small one on the PTO it's self. and again on the PTo pump ya want around 230-245 PSI on that one . your hitch pump as for pressure depending on if the pressure relief is stock or been changed could be 1750 to 2300 PSI

 

[TimWafer]

I greased everything in the front end again and lifted it off the ground & tried it. Even jacked up, there seems to be abnormal resistance turning the steering wheel. I can hear a little whine if I'm standing next to the MCV valve while steering it that i couldn't hear from the drivers seat if that's significant. My hearing is not great. I finished plowing with it yesterday and both my shoulders ache today. I used the TA and brakes a lot yesterday and both of those still seem to work fine. TA seems to kick in and out quickly.

I'm still waiting on a manual but if I knew what ports to test the pressure at I could try to come up with fittings, hoses and a gauge. I remember testing pressure on both the 656 PTO once and the 706 PTO as I had it out to replace a broken shaft and put new clutches in it when I bought it. Still should have that gauge setup somewhere.

 

[the tractor vet]

At the moment my thinking is myself i would start with the flow control valve then move down to the steering orface then onto the Pilot control valve . ya need 3 gpm for steering and somewhere between 1250 and 1750 Pis i think . I would have to look to be dead sure . . Does your dash oil lite come on when you depress the clutch??? does it even work?? This OIL light does double duty as and engine oil and T/A pressure . If it was loosen pressure in the M C V then it would come on or flicker . Alot of people think they know I H tractors but there have been only a couple of us on here that really worked on them everyday for years . Yea sometimes i would get stumped and it may take awhile to get it all sorted out. Setting here on the magic box is NOT the same as having hands on . And tryen to figure it out from hearsay makes it hard. Being with the tractor it would just be a matter of walking over to the truck and getting the gauges out and hooking up the flow rater , Around hereother then a dealer i am the only one that has a flow rater . Mine is and older one bu i can do up to 50 GMP and 5000 Psi , not big enough for some of this NEW stuff and i can not do the PFC systems on the newer I H tractors .