Rich Grise wrote:

justme wrote:

I have a IH-3400A backhoe in decent condition but the power steering
has gone out. It started failing by working intermittently and now,
it is completely gone. Yes, it has fluid. Sometimes the steering
wheel will turn if you put a great about of force on it and the front
tires will turn. At other times, the steering wheel will easily turn
but not front wheel action.

I do have a limited service manual for the machine showing the flow
for the steering. I was thinking of getting a 0 to 4500 p.s.i. gauge
and working down the line to see where I am not getting pressure but I
don't know what I am doing.

Any ideas that don't cost an arm and a leg?

About the only thing I can say for sure is that, at least on cars, the
power part is only "power assist" - it's fail-safe, in that if the pump
goes out, you can still steer the car by way of the mechanical linkage,
if you're stronger than Aunt Tillie. ;-)

I'd look into that first - Pitman arm, idler arm, drag link, tie rods,
that sort of thing, before I'd start troubleshooting the hydraulics.

If it's entirely "steer-by-wire", so to speak, then, yeah, your plan
is what I'd probably do. Intermittent pump, worn spool valve(s), leaky
cylinder(s) and so on.

Has it recently had any trauma where you could have a bent component?

These are normally 100% "steer by hose" and normally run from the main
hydraulic supply so if the rest of the machine is working properly the
hydraulic pump is fine. Almost certainly it's an issue with the rather
complex hydraulic steering valve.