justme wrote:

Pete, what you said below confuses me. The s. wheel is hard to turn
and the tires have not reached near their limit. It seems that a
short time ago, I could rotate the s. wheel easily but I am not sure
if the engine was on or off. Regardless, the tires didn't turn.

Think about how the steering system works:

You have a double acting steering cylinder connected to the wheels. You
have a steering valve that connects to the steering cylinder and also to
a supply of hydraulic pressure and a return to the tank. Just like a
typical 4 way control valve, the steering valve will provide pressurized
fluid to one side of the cylinder and allow fluid from the other side of
the cylinder to return to the tank.

The steering valve is designed so that for every movement of the
steering wheel, a small amount of fluid is allowed to travel to one side
of the steering cylinder and a small amount to return from the opposite
side. The direction you are turning the steering wheel determines which
side of the steering cylinder receives the fluid and which side the
fluid returns from.

There are two types of steering valves, load-reaction and non
load-reaction. The load reaction type is designed to provide a level of
feedback to the steering wheel to provide some resistance when you are
turning the wheels against an object or the like. The non load-reaction
provides no feedback, so you can turn the steering wheel with one finger
while the machines wheels are pushing it sideways off a rock.

If you have a load-reaction type of steering valve, the only time you
will feel resistance in the steering wheel is when the wheels are
pushing against an object, or are turned to their limit. With a non
load-reaction steering valve, you illl never feel resistance in the
steering wheel.

If the steering cylinder has an internal leak, it would allow the fluid
to pass between ports without moving the cylinder piston. This would
allow the steering wheel to freewheel with no resistance and without the
wheels moving, one of the conditions you said you had.

You also said you had the steering wheel difficult to turn with the
machine jacked up and with the wheels more-or-less straight ahead. Since
this is clearly a case with no side load on the wheels and the wheels
not at their turn limit, there should not be any resistance in the
steering wheel, even if it is a load-reaction type valve. This condition
could not be caused by internal leakage in the steering cylinder. If
it's a non load-reaction valve it shouldn't have resistance at all. I
believe most construction equipment will have non load-reaction steering
valves.

This is a bit over-simplified, but it gives you the overall idea. The
bottom line is that the symptoms you are seeing are most likely from a
failing steering valve and a rebuild is in order.


Yesterday, with the engine running, I loosened on of the fittings on
the cylinder and fluid came out then, I rotated the s. wheel and more
came out.

That test doesn't really tell much, that's more or less what should
happen, however without the cylinder connected (effectively) you didn't
have return fluid flow from the other side of the cylinder, nor any back
pressure, so the internals of the steering valve were not fully
activated.


I shot you an email.

It didn't get through. You have to remove the anti spam stuff to "34" to
get through.