Ford Backhoe 555B steering problems

I have a 1985 ford backhoe 555B. After overloading
my front end the steering become unresponsive. I
can only turn wheels rt. & lft. with the weight
taken off front wheels. I can steer somewhat with
forward motion and no frontend loads. I have
checked pump pressure and found pressure turning
left to be 500 - 1000 at the stop (steering wheel
stops at this point). Right pressure only 200-300
with no stop in the steering wheel. Steering wheel
keeps turning even with rt. wheel completely
turned. Pump has no foam. Before this problem I
changed the left wheel steering cylinder for
excessive leaking. Steering was fine until the
overloaded front end bucket. I have put a seal kit
in the right wheel cylinder, and a seal kit in the
pump. Thanks for the help..........larry

Sounds like broke something in hand pump. Torsen pin?

Without isolating the components, you are guessing. Pump pressure is tested by deadheading pump flow momentarily. Then test orbit motor (hand pump) output to the steering cylinder(s) by deadheading the lines to the cylinder(s). then test the cylinders individually if 4WD or teat the single cylinder on a 2WD.

One needs to be careful when dead-heading those Ford PS pumps. On later models, the relief valve is in the steering motor, so a test like that could lead to a big-dollar failure.

Also, I have never found the dead-head test to be very accurate to be honest. There are many Ford PS pumps out there that will make rated pressure, but with virtually no flow behind it because it is so wore out. Best way to test a pump like that is with a flowmeter.

Momentarily deadheading the pump to check system pressure is clearly spelled out in the 555A/555B/655A Ford repair manual that I have in front of me. If a method is good enough for Ford to publish, I don't have a problem passing that along. Is a flow meter better? Sure. Most guys that post here looking for help don't have sophisticated test equipment or the desire to pay shop rates to hire them. A 3000 PSI gauge isn't hard to come up with. A 555B P/S pump will have a built-in relief valve set at or near 1600PSI, just like the series that preceded it and the 'C' and 'D' series that followed.

My caution was for Ford tractor PS pumps in general, not 555B models specifically. I'm not as up on idustrial models, but I do know that later 7610s (late 80's) had the relief valve in the motor, so again, one needs to be careful and not assume that all Ford PS pumps can be safely dead-headed. Same goes for engine-mount hydraulic pumps.

I realize that most guys on this board will not run out and buy a flow meter, however it's also safe to say that there are a lot of half worn out Ford PS pumps out there that would in fact pass the factory-prescribed dead-head test (especially with cold oil) that might cause a fellow to start chasing their tail in other areas.

I realize that the dead-head test is spelled out in the factory repair manual, but this is one instance where the factory method is definitely not good enough for me.

Agree with you about caution on those pumps Bern...
I'm not arguing the point of wether or not the 555 has a releif in the pump... but as you suggest, many 10 and 30 series pumps had a flow control in the pump and the releif in the steering works.

For what it's worth, I find the quickest and easiest test for those pumps is dis-assembly. It doesn't take much more than 10 minutes to pop the resevoir off and unbolt the back plate and pull the gears. A quick viewing of the bushings will ascertain what's left of the pump... which is generally not much on most I've seen.

Rod

RickB, Thanks so much for taking time to respond. This is my first time using this forum. You sound much more knowledgeable about Ford tractors than myself. I am strictly a jack leg, with some mechanical background. Not sure I know what dead-head refers to. The ford tractor dealer I have been able to gleam some info from, told me that first I must determine the pump pressure. He said it should be appx. 1200-1500 at the stops (wheels turned completly I assume). I purchased a hydraulic pressure gauge and installed it with a T connector in the output line. With engine running pump reads 0 pres. until the steering wheel is moved at which time it reads about 500 psi to the left and only 200 psi to the right. This is with the front wheels full on ground and wheels only turn slightly. If I raise front wheels off ground I can then turn left to the stop and gauge reads 1000psi. To the right however wheel turns completely to the stop but steering wheel will keep turning and pressure is only 500psi. I removed the pump, disassembled, order a seal kit and replaced kit seals. Pump looked tight internally. problem still there. I have since taken out the steering motor and disassembled. Very intricate device. Internally it looks like a small rotatory engine. Internal parts look to be ok, haven't gotten motor back together yet. I have also removed and inspected the wheel cylinders and both appear in good order. I suspect my steering motor. New, this item is $1K. Do you know of any sources for used parts of this type? P/N 86604767

RodInNS, Thanks so much for taking time to respond. This is my first time using this forum so bear with me. I am sending this expanded version of my problem to all responders. You all sound much more knowledgeable about Ford tractors than myself. I am strictly a jack leg, with some mechanical background. Not sure I know what dead-head refers to. The ford tractor dealer I have been able to gleam some info from, told me that first I must determine the pump pressure. He said it should be appx. 1200-1500 at the stops (wheels turned completly I assume). I purchased a hydraulic pressure gauge and installed it with a T connector in the output line. With engine running pump reads 0 pres. until the steering wheel is moved at which time it reads about 500 psi to the left and only 200 psi to the right. This is with the front wheels full on ground and wheels only turn slightly. If I raise front wheels off ground I can then turn left to the stop and gauge reads 1000psi. To the right however wheel turns completely to the stop but steering wheel will keep turning and pressure is only 500psi. I removed the pump, disassembled, order a seal kit and replaced kit seals. Pump looked tight internally. problem still there. I have since taken out the steering motor and disassembled. Very intricate device. Internally it looks like a small rotatory engine. Internal parts look to be ok, haven't gotten motor back together yet. I have also removed and inspected the wheel cylinders and both appear in good order. I suspect my steering motor. New, this item is $1K. Do you know of any sources for used parts of this type? P/N 86604767

Bern, Thanks so much for taking time to respond. This is my first time using this forum so bear with me. I am sending this expanded version of my problem to all responders. You all sound much more knowledgeable about Ford tractors than myself. I am strictly a jack leg, with some mechanical background. Not sure I know what dead-head refers to. The ford tractor dealer I have been able to gleam some info from, told me that first I must determine the pump pressure. He said it should be appx. 1200-1500 at the stops (wheels turned completly I assume). I purchased a hydraulic pressure gauge and installed it with a T connector in the output line. With engine running pump reads 0 pres. until the steering wheel is moved at which time it reads about 500 psi to the left and only 200 psi to the right. This is with the front wheels full on ground and wheels only turn slightly. If I raise front wheels off ground I can then turn left to the stop and gauge reads 1000psi. To the right however wheel turns completely to the stop but steering wheel will keep turning and pressure is only 500psi. I removed the pump, disassembled, order a seal kit and replaced kit seals. Pump looked tight internally. problem still there. I have since taken out the steering motor and disassembled. Very intricate device. Internally it looks like a small rotatory engine. Internal parts look to be ok, haven't gotten motor back together yet. I have also removed and inspected the wheel cylinders and both appear in good order. I suspect my steering motor. New, this item is $1K. Do you know of any sources for used parts of this type? P/N 86604767

What is the hand pump? thanks much .Larry

You've most likely either got bad steering cylinders or a bad steering motor.
It's probably 5 years since I had a motor in pieces so my memory is getting foggy. IIRC, most of the action happens in the bottom section of those things and they're a gerotor type of pump/motor. Pay very close attention to the end plates and their wear patterns... and also make sure that you don't force anything putting it back together or you can break some rather expensive parts. Yours kinds sounds like mine did after I broke (cracked) the commutator ring when I put it back together. Just look at it very closely.
Beyond that I think I'd put it all back together and put oil in it except... instead of hooking up the cylinder lines... plug them where they come from the steering motor. Then start the engine and turn the wheel... or try to turn the wheel. I believe with the lines plugged it should act the same as the cylinder against it's stops.... so the wheel should NOT turn once the lines are purged. (Might be good to couple them together to bleed the system first, then plug them.)
If the wheel does turn with the lines plugged then I would wager that the steering motor is bypassing internally. if everythign holds up tight... I'd expect a cylinder problem.

Rod

Thanks to all my responders. Still have steering problems on my 1985 ford 555B 2wd tractor. Recently I removed and disassembled my steering motor and saw nothing unusual. This item must have a thousand parts, much like a swiss watch. Still thinking that the st. motor was my problem, I ordered a used one ($500) and installed. Still no help. Steering is hard and only with tractor in motion or front end raised can you turn wheels through complete range. I have again removed my two wheel cylinders to dissasemble and inspect. Before the steering problem occured I had ordered a seal kit for one of the cylinders that leaked badly and I could not replace all the o-rings in the kit because I could not remove the inner tube from my cylinder. Does anyone know how this is done? After I replaced the 0-rings the cylinder worked properly without leaking and steering was good until the overloaded front end and resulting hard to no steering functions. Thanks again ....Larry

If you're willing to throw $500.00 at a replacement steering motor without knowing what the problem actually is, you might as well take the steering cylinders to a local hydraulic shop and have them rebuild them instead of trying to rebuild them yourself if you're unsure of what you're doing. At least you'll know that the cylinders are good at that point.