Please Diagnose: Power Steering Problem

[Travis_R]

Something is going on with the steering on my 1998 Massey Ferguson 231 tractor. It has hard spots that wanna stop the wheel from turning mainly when you turn to the right. It will do it to the left also but not near as bad.
At idle it seems to steer fine but when the RPMs are up it struggles to steer.

Do you have an idea of what's going on? The tractor has 1,315 hours. I can send pics if needed.
Thank You

 

[flyerdan]

Can you get the wheels off the ground and see if it behaves the same way? It doesn't appear that you have a loader so it won't be quite as easy.
If it's still rough, I'd suspect that the steering box has some debris in the ball bearing track, probably from a bearing disintegrating. That doesn't explain the easy steering at idle though...

 

[2458n]

I have power steering issues with my Frontier truck and diesel 4x4 dually. Tractor is fine. Wish you a simple solution.

 

[boggen]

AGCO Parts Books -> guests -> massy ferguson from drop down menu -> 231 -> search = online part listings.

--gotta ask the obvious. are you actually moving? vs standing still and in neutral?
--are you low on fluid? looks like you need to check a small tank, just above "steering pump" itself. or check steering pump itself for fluid level (a tad hard to tell from diagrams)
--can you turn steering wheel and takes a little more turning for wheels to actually turn? (as in air in the hydraulics, or hydraulic oil leaking around valves or cylinders)
--is there any play in steering wheel itself? as in physically turning it back and forth then finally you hit something and tires finally begin turning.
--looks like you have 2 hydraulic cylinders (1 per front wheel) if i am looking at part diagrams correctly. are they bent?
--looks like a very generic simple "steering valve" modify "spool valve" that a FEL or rear remotes use in a sense. i see some 0-rings. that might of gotten torn up?
--looks like there is some bearings between the actual steering wheel itself, and then the steering column that goes down to the steering valve.

 

[Travis_R]

Sorry for the late response...

The tractor has difficulty steering while moving, not sitting still, but no problem at idle.

It does not have a loader on it.

Didn't think about jacking up front end to check for resistance.

There is a significant amount of play in the steering from left to right when engine is killed.

I noticed with the fill plug out, engine running, and pump filled to full mark it didn't look like much oil was circulating like it used to do.

How could I tell if fluid is bypassing internally in the pump or the right side cylinder?

Left side cylinder was rebuilt last year by a Massey Ferguson dealer. I shipped the cylinder to them. It was leaking bad externally.

What kind of fluid should go in the power steering pump?

Got a new power steering filter today, will install tomorrow.

 

[spokane 1]

I don't know furggeys but Ive seen this problem before in steering units in general there is a decider(feeler valve) that is bad. when you turn the wheel the feeler then jets hydro fluid to the right cylinder and at the same time releases fluid from the opposite cylinder. thus you can steer.
but when the valve goes bad it refuses to release fluid from the opposite cylinder from the way you want to steer. and you have dead spots or a locked steering wheel while your turning in tiny don't want to budge moments.

its either a bad valve or dirt in a valve.

 

[Travis_R]

Is this the same as a control valve or selector valve?

 

[spokane 1]

I assume not knowing your machine that this device is inside the steering box , on some tractors its all just right up by the steering wheel. Its a nice small box with one hose in 3 hoses out. 2 pressure lines to each left right wheel cylinder and one return hose to the main pump in the trans axle.

if your steering rams are tilted there could be air in one...but usually they are mounted level. the way to bleed them is jack the rig and fire up turn one complete cycle full left then right....and its all done.

 

[Travis_R]

Does the power steering pump share the same fluid as the steering gearbox?

 

[spokane 1]

Does the power steering pump share the same fluid as the steering gearbox?

all the tractors Ive worked on all came from one transaxle pump,, they usually have a constant thru shaft drive...pump drive that also runs the pto..when the tractor is stopped clutch in the pto still runs until its disengaged. the pressure is piped along the case back up to the steering box just under the plastic shields at the steering wheel.

 

[Travis_R]

I can do some work on atvs, lawn mowers, weed eaters, and change brakes on vehicles, but would give up some of those things to diagnose power steering problems on tractors!

 

[Travis_R]

I bought the "Traveller Premium Trans/Hydraulic Fluid" at Tractor Supply earlier today and put it in my tractor. It came in a 2.5 gal. jug. Didn't have any quart bottles. The oil is compatible with many, many makes of tractor fluid requirements/specs.
O'Reilly auto didn't have anything compatible with Massey Permatran III.

It still didn't help with the steering problem but I'm going to keep using this stuff because of the compatibility. I was using Valvoline ATF High Mileage Synthetic fluid. Red, Dexron III.
Had been in the tractor for about 700 hours, so maybe it was good stuff I don't know. My tractor sits more than it's used. I've had it for 9 years and put 835 hrs. on it. That's only about 93 hrs. a year.

 

[gordo350]

I had a similar problem on my mf135. Took the pump of the motor and pulled it apart. Turned out a gasket on the pressure side blew out. Replaced the gasket. All good as new. If you fill the reservoir to the brim you should see the level drop when you move the steering wheel. If it doesn't it may be the valve on the steering column. Sometimes the connection comes adrift. Think it has a couple of split pins holding it on. Hope this helps

 

[boggen]

if ya going to DIY. ya might as well go all in. and start tearing it apart. from steering wheel and working your way down to the steering valve. taking it apart, cleaning it up, checking bearings, and sprockets/gears as you go. worst comes to worst, you fail, and take it to a dealer. then again you might find a $2 to $30 buck fix. vs a $400 buck fix.

guessing at most you will need a "steering wheel puller" and maybe a "bearing puller" if bearing needs replaced, beyond the general wrenches, socket wrenches, screw drivers, torque wrench, snap ring pliers/removers/installers. maybe a star bit, or an alen wrench.

===========
some times you can use same hydraulic fluid you use for FEL and/or rear remotes, or possibly transmission for the power steering fluid.

 

[Travis_R]

The culprit, or close to it?

May have found the culprit, or close to it?

Ok so I decided to take some sheet metal off and look at that control valve thing on the steering column. Looked like it had 2 lines coming out of it on each side. Maybe another line I don't remember.
I watched how it functioned by turning the steering wheel with and without the tractor running.

There is a threaded piece that connects the control valve to the steering column I guess you could say.
The threaded piece can be adjusted up or down (which I guess would be in or out in the control valve).

The threaded piece that connects to the piston (maybe?) in the control valve is barely moving up or down (or in/out) when the steering wheel is turned.
With the engine killed and tires on the ground it moves about 1/4 of an inch.
With the tractor running at high idle and tires on the ground, the piece in the control valve doesn't move at all, but I do have some power steering.
Is this normal?

Also, I think I'm seeing air bubbles in the power steering pump. Trying to post a couple pictures...

 

[Travis_R]

Pump & bubbles

2 Pictures right here hopefully...

 

[boggen]

if memory serves, when i was looking at agcopartsbooks. that tank directly above the steering pump. = your fill location for steering fluid. and not on the steering pump itself. (((if this is the case))) i would say you are low on steering fluid.

and looking at the location on the steering pump were you have taken pictures, looks like there was an "0-ring" or something there for a nice tight fluid tight fitting / cap or what ever was connected there. leading me to believe you are low on steering fluid and you are getting air into your system due to low fluid.

 

[gordo350]

Don't know what the tank on top does but the lower opening is the correct level for fluid. I think you may be on the right track with the control valve movement or lack of

 

[Travis_R]

if memory serves, when i was looking at agcopartsbooks. that tank directly above the steering pump. = your fill location for steering fluid. and not on the steering pump itself. (((if this is the case))) i would say you are low on steering fluid.

and looking at the location on the steering pump were you have taken pictures, looks like there was an "0-ring" or something there for a nice tight fluid tight fitting / cap or what ever was connected there. leading me to believe you are low on steering fluid and you are getting air into your system due to low fluid.

The fluid is not low. There was a sticker there that read "cold fill line do not fill above bottom threads.", or something along those lines.
The "tank" is just there for a vent when too much pressure builds up or too much oil is in it. It will force fluid out the top. The metal piece on top is spring loaded and I guess it's set for a certain pressure relief from the factory.

 

[Travis_R]

No luck yet!
Anybody reading this have the solution?
Adjusting the control valve linkage didn't change anything.
Could it be the pump?
How can I tell if the pump is bad?
I've ran the pump almost dry a few times when the left cylinder started leaking bad a couple years ago. Got so bad it had to be re-packed. That was 2 years ago and now just starting to have steering problems that I can't seem to diagnose.
If anybody can help me, PLEASE do. have got to get this hay baled ASAP.