In need of hydraulic help

[chet]

I'm having steering problems with my old backhoe. I suspect the culprit may be the Char-Lynn Orbitrol steering control. Are these a real bugger ta work on? And does anyone know if there is a limit stop on these, on this one I can keep spinnin' the steering wheel. I can't remember if I could do that when it was working properly.  :-\

[J_T]

I think burden surplus has those crar-linn stearing units sometimes  ???

[Tom]

Put some fluid in it. 

[chet]

Put some fluid in it. 

Dat thought did cross my mind.............but it didn't help.  :(

[isawlogs]

I was gonna tell ya that ya still had brakes to steer ... but I refrained myself from doing so ... then I decided against myself and decided to tell ya .  ;D

  I had that happen to my skidder and you'd think I could remember what was done to  cure its ailment ... I even called my dad about it ... He just rolled his eyes and well I wont repeat it you would not understand anyways it was all French dialect .  ;D

  I do remember changing the oil filter and having to drain the oil .. what a pain . This was on a JD skidder .

[pigman]

I took one of those orbitrol steering controls apart once thinking it was the problem. : Then I got a mechanic to help me put it back together. He then showed me the real problem, an O ring had blown in the cylinder that moved the wheels.

[chet]

Brakes won't work ta steer as ders only a disc on da drive shaft. And ta make matters worse it's 4x4.
I did a pressure check and da pump and fluid flow is fine.

[footer]

I took one of those orbitrol steering controls apart once thinking it was the problem. : Then I got a mechanic to help me put it back together. He then showed me the real problem, an O ring had blown in the cylinder that moved the wheels.

That is probably correct. If the cylinder piston packing is blown, the fluid will basically bypass the piston and return to the valve. the cylinder stopping at the end of it's travel is what makes the steering wheel stop turning.

[Nailhead]

Me too thinks it's the cylinder piston seal. Try removing one lin e from the cylinder and capping it and the cylinder port and see if the steering wheel stops. If it does, it's probably the cylinder packing. If not then I would look for a relief valve stuck open.

[isawlogs]

  After cogitating this I remembered having the steering cylinders repacked and the streering valve cleaned out ... Oil change and filter . all worked fine after that .

[chet]

Thanks guys     I'm gonna hafta wait 'till I get a couple of days off and start doin' some pressure checks. Then start isolating one cylinder at a time. The machine has 4 steerin' cylinders as it has oblique steerin' capabilities.

[isawlogs]

Hey Chet ,mind if I ask what " oblique steerin' capabilities " is  ???  :-\

[chet]

It means all the tires are capable of turning the same direction at the same time. Makes for bein' able ta drive sideways.      Great for gittin' inta real tight spots.  8)

[Timburr]

Chet, one symptom of leaking cylinder piston seals is the vehicle having a steering bias to the left OR right..... when travelling on uneven ground or side slope in a straight line, the steering needs to be constantly adjusted to the left or right to keep the machine running true.  Now the headache arrives....  which cylinder?

If hyd. pressures are up, other steering maladies could be debris in the orbital valve.   The valve has a myriad of small metering orifices, which are the last stop for a whole plethora of broken bits.  :D

The steering stop is just a dowel in an elongated hole that allows the orbital valve to function, but limits steering wheel travel.  Depending on application, the dowel can be removed for conventional steering.

A word of warning, should you need to go into the orbital valve, some of the ones with a "gear pump" at the valve base need to be "timed", otherwise the machine will self-steer without any participation from you.          We would hate to hear of your arm in plaster-cast!