Ford 3000 weak power steering

I've got a later model 3000 diesel with power steering and the power steering is very weak. I put a pressure gauge on the outlet line of the pump, and at 1000 RPM, it sits around 200 PSI. If I turn the steering wheel either way, I can see the cylinders slowly responding and it's very easy to outrun them with just the steering wheel. When I hit the stops, either direction, the pressure gauge doesn't change. The steering wheel moves up or down ~.1 inches when turning, and there are no external leaks in the system. I'm guessing the problem is somewhere in the control valve, but I have no idea where to start. Any suggestions would be appreciated.

If the steering wheel is rising an lowering that much and it's not leaking, then it's most likely that the nut that is supposed to hold the control valve in place has become loose. Follow the procedure in the service manual on tightening that nut down, which includes backing it off once it's tight by some specific amount (1/4 turn or 1/2 turn or something like that, I can't remember the exact amount for that model off the top of my head) and then staking the nut in place so it doesn't turn.

The steering wheel is supposed to rise and lower when you turn it, but the total amount is supposed to be something less than 1/4", like 3/16" or something like that.

I'm thinking .1" inc rise and fall of the
wheel is about normal.
What is the history of this tractor?
Just bought it and are working out the
kinks?
Owned it for a while and it got worse or
happened suddenly?
I would leave the control valve alone for
now and look at the pump.
When you open the reservoir while its
running does any oil boil out?
If so, replacing the filter is not expensive
and maybe worth a gamble.
If the tractor is new to you the previous
owner might have run it with the pump dry
and it wore itself out inside.
A new pump isn't sooo expensive either but
try a new filter first.

The tractor came a few years ago with aftermarket steering and I decided to put a loader on it which the steering wouldn't support. I was able to source most of the parts I needed from a local junk yard to convert to OEM power assist steering. I re-used the pump and reservoir from the aftermarket system (anadolu if that matters). The system didn't leak, but didn't really do much, so I assumed it was the pump. I installed a pressure gauge and it read around 250PSI. I ebay'd an OEM pump from a 3600 (seller said it worked fine if you believe him), and put a new filter in when I installed it. I did run it with the the reservoir open and it looked like the oil was foaming up but it didn't "boil over" and I only ran it for a few minutes. Since I had two different pumps with similar readings, I figured I'd ask before I threw more money at the pump. Would it be wise to put a shutoff valve in the line and very briefly dead head the pump to check pressure?

Amusing anecdote when I did the conversion - I could only find one cylinder at the bone yard so I had to buy a new one online. That new cylinder was the only part that leaked when I fired it up. :shock:

Sorry, I thought it said 1", not .1".

pressure on the pump... with the wheels in lock position for only a short time... as it will over heat the pump.... should be 650 lbs. but will read between 600 and 700 in actual testing.... per the it manual with a tee fitting in the pressure line.

I believe your 200 lbs is too low. And in my experience all the used pumps I bought were removed because they were bad, so I found out early on that used pumps are not the way to go.

As to the power steering on a 3000, it is NOT power steering, but power assist... as its always a bit lagging and you can out run it easily if you turn very fast. It will always require a bit more pressure to turn the wheel than any car, but.... compared to NO power steering, it reduces the required pressure dramatically. The 3600 and the 3610 had huge improvements in the required turning pressure.... so much so, that they put on a smaller steering wheel.

So I dead headed the pump and started the tractor and the pressure shot up over 600 at which point, I shut the tractor off to avoid pump damage. As I mentioned before, there's no pressure change when I turn the wheels to the stops either way, so I'm back to something being amiss in the control valve, ie when I turn the wheel, it opens flow to the cylinders but doesn't shut off the return, asuming the valve is an open center configuration. Is there a schematic of how the control valve works available anywhere or any suggestions of what to check next? I appreciate the help.

(quoted from post at 14:03:49 04/21/18) So I dead headed the pump and started the tractor and the pressure shot up over 600 at which point, I shut the tractor off to avoid pump damage. As I mentioned before, there's no pressure change when I turn the wheels to the stops either way, so I'm back to something being amiss in the control valve, ie when I turn the wheel, it opens flow to the cylinders but doesn't shut off the return, asuming the valve is an open center configuration. Is there a schematic of how the control valve works available anywhere or any suggestions of what to check next? I appreciate the help.

Click to expand...

The return is always open in an open center control valve. When the valve opens to power one side of the cylinders the fluid being pushed out the other side of the cylinders needs someplace to go, which is back through the control valve and on through the return line to the sump. I would suspect a bad internal seal in one or both cylinders that is leaking everything higher than your originally measured 200 psi through from one side of the cylinder to the other.

Never thought to question the cylinders! I pulled the lines for both cylinders this morning and plugged the ports in the control valve. Still no pressure change when I turn the wheel and I did confirm that oil is flowing back into the reservoir with all four cylinder ports plugged. I'm wondering if the check valves are stuck. I guess the next step is to pull the control valve apart and see what's what. Thanks for all the help and suggestions! I'll post back once I've figured it out. Might be a while. I'm out of town this week (lucky me :roll: )