# Massey 550 steering problem



## Biker

It's my neighbours tractor, he's asked me to help out, 
I asking you the same thing.
'You can turn the steering wheel around and around many times to try to get some response'.. Was his description of the problem.
It is power steering, I havn't been there yet to try it, 
but I'm the one who has to fix it., is what neighbours do..
I don't have any idea about what it could be, yes there is oil in the pump, the belt is ok and tension ok.. No leaks or squeaks..
yes I have good mechanical understandings, but no experience with this issue.
Any ideas.. Thanks in advance, I'll follow through with it ok. Ian


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## BigT

Welcome back to the forum Biker.

That tractor has a steering motor, which explains why you can turn the steering wheel many turns with little response. My only experience with a steering motor is my neighbor's Ford 3930. His worker drove it till the steering quit totally. When I checked it, the pump reservoir was empty. Seems like I added quite a bit of fluid, but it gradually started working again, No problems since.

Double check with the neighbor that he (or someone else) didn't add fluid to the system recently, because the steering wouldn't work. May have air in the system. A simple thing to try is to jack up the front axle and make it steer full right, keeping the reservoir topped up. Then steer full left again keeping the reservoir topped up. 

If the above doesn't work, check the pump output pressure, using a 1500 psi gauge.


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## Biker

Something new for me to get my head around.. that's good.
So what does the steering wheel do ?
The pump is seperate, and the power cylinder is seperate, naturaly..

How does the steering wheel interact with the 'steering motor' and what is a steering motor.. ??

I know the pump will supply hydraulic pressure to the system..
I would imagine the steering wheel operated a valve body, but not in this case.. 

I would like to understand it more fully..

Yes I will visit soon and as you say, try to 'bleed' the system with left and right.

I will have to look into the pressure test if that fails..

Hey thanks for your time and attention.
We'll see it through.


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## Fedup

I can't state for certain, since the 550 is a tractor I've never seen. I don't think it was marketed in North America, but Tractor Data lists it as having hydrostatic steering. My guess is there is only one external steering cylinder(possibly two) and the problem is nothing more than bad piston seals in said cylinder. Probably not a difficult nor expensive fix. 
As for "problematic steering systems", yes Massey did produce a number of different models, like a 230, 231, 235, etc, some of which had inherent problems. Tractors with hydrostatic steering were not on that list.


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## BigT

I can offer only a very basic explanation of "hydrostatic steering" as compared to the older "power assist steering" systems found in tractors:

Power assisted steering still has a complete mechanical link (via steering gearbox)between the steering wheel and the front tires... It is just hydraulically assisted. If the power steering system fails, you still have the mechanical link through the steering gearbox. It just becomes "grunt" steering.

Hydostatic steering has no mechanical link (no steering gearbox), and depends strictly on hydraulics for steering control. If the hydrostatic system fails, there is no steering control. The steering wheel can turn freely with no response. Your only option is to use the brakes to "steer" the tractor. 

The steering motor is basically a rotary hydraulic valve that supplies fluid as it is turned. 

Hope this helps.


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## Biker

Thanks guys I understand what you said, The way he described it had me confused, Yes, a 'rotating' valve to direct hydraulic pressure to one end or the other 
of the single cylinder on the steering rod arm..

Sounds like lack of pressure.. pump problem, oil or air (not belt)

Valve blocked.. ??

I'll be back.. always wanted to say that.


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## Fedup

If the steering wheel moves freely in both directions with engine running and the tractor fails to steer, then your problem is not pump, not air, nor is it a blocked valve.

It's piston seals! Always wanted to say THAT.


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## BigT

As Fedup suggests, I would definitely check the cylinder for leaking piston seals. Rebuild it or have it rebuilt.

I understand that the valve rarely has problems.


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## Biker

With the front end up, I bleed the system by cracking the fittings ate the cylinder..
I had 'imagined' that on of the feeds would be a hi-pressure, the one doing most of the work.. But not so on the left side, which is the problem side.. the 'leak' from the bleed was pretty poor on both fittings.. Hmmm

On the right hand side, I got a good solid squirt from one of the fittings.. Heh

So maybe on the left the oil is pushing past a worn seal ??
Since the left is turning, but badly so.

I had thought, oh well must still be some air, so it will work it's own around the system..

But now having thought it through and read ur post about the seals, I'm thinking the problem on the left is just that..

Any thoughts on the issue.. 

Thanks ur time and attention, if you's need a hand
give me a call.
Ian


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## Fedup

With two cylinders it does complicate the diagnosis a bit. Most likely the cylinders are supplied though tee fittings, so oil flow from the valve splits and flows to and from both cylinders at the same time. What you can do is jack up the front end, turn the wheels to full lock in one direction. Then determine which line supplies fluid to move the cylinder rod in that particular direction. Most likely it will not be the same on both cylinders, as they are usually plumbed opposite each other so one extends while the other retracts. Once that is determined and the steering is fully to one side, remove the lines from both cylinders on the opposite side from the pressure applied. Start the tractor and try to steer in the same direction. If all is correct(meaning piston seals are both good) both cylinders will bottom out and oil flow will stop. On the other hand, a bad seal will allow fluid to pass by, exit the open port and run out on the ground. If you see that, then this is the cylinder to concentrate on.


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## Biker

Well said Fed-up, I would that.. Though the Farmer, Ray, has decided to get a set of seals and I have agreed to have a go at fitting them for him, can't be that difficult since it is a remove and replace job, and I am a fitter, so I know about clean and tidy with hydraulics.. it is an old machine after all, and has done a lot of work, it shows.. but he's happy with it.

He has asked about topping the gearbox up, the filler is near to the gearlever on top of the box, but we can not find the level plug or any sort of dip stick.. any clues, we have no paperwork, maybe I should google it, but maybe someone knows..

Here's one for ya, a freebie.. 
He said it was heavy on batteries, and needed another one.. since he had no reds and it wouldn't start 'again'.. Well I found good voltage at the battery but next to none at the starter, it would not jump at the solinoid eigther.. Hmm, changed the battery but similar results, another Hmm.. you guessed it, the Earth cable had been changed at the chassis to a small painted bolt up agains a rusy hole.. hahah Well he was so happy to see them reds and hear it start straight away made my day just to see him so happy.. a little knowledge can go a long way.


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## RC Wells

If my recollection is correct the 550 uses a diverter to send hydraulic pressure from the common hydraulic system to the steering valve (hydrostatic valve). My assumption is the hydraulic filters are clean and flowing properly and the system has plenty of pressure.

There are three things to check:
A) Most common problem is dry front king pins. Jack the front end up, get the weight off, remove the hydraulic cylinder(s) or crack the lines and let oil squirt everywhere as you move the front wheels, and then try to turn the front wheels from right to left, etc., with the engine turned off. If they are stiff from lack of grease or the accumulation of dirt and wear particles over time, and will not easily turn from one side to the other, you have likely found your problem. The diverter valve detects over pressure in the hydraulic system, and if the steering is stiff the diverter essentially shuts the flow off to that hydraulic circuit to avoid damage.

B) Diverter valve for pressure beyond the main system to feed the hydrostatic steering valve. With the hydraulic lines open (this will be messy) start the tractor and twist the steering wheel from right to left, etc. If you have good pressure on either side, the diverter is functioning properly. If one side is not responding go the the next step.

C) The hydrostatic steering valve itself may be stuck in one position. The tell here is pressure on one side when the engine is running and not on the other as you turn the wheel. Again the cause is either excessive wear, around 15,000 hours, or contaminated oil has caused the disc(s) that controls the flow from right to left have stuck to one side, the middle, or the other. The fix is rather simple, remove and clean the valve, or have it rebuilt.


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## Biker

Thanks RC, the puzzle is coming together..
At present, it turns right as it should.
Does not want to turn left..

When I cracked the fittings to the cylinders, to bleed after a re-fill. 
Right side had good pressure squirted all over..
Left side it just dribbled out both limes.. 
I presumed the seal was worn on the left side and not able to hold a pressure.. 

Firstly I'll check the king pins as described, if ok then it's likely a pressure problem, maybe the diverter disks to that side are a bit iffy, stuck or dirty..

I never thought to check for king pin movement, but if it turns one way ok
then the pins must be ok, because it turned, but then again, not well..

The problem is isolated to the left hand turn..

Now with more exposure to the issue, I can take more notice of were the pressure is and is not in relation to the cylinders, ie: check what I have found allready, it sounds like the left side is just not getting the pressure needed, oh dear the farmer has ordered cylinder seals..

Thanks all for your time and attention, he needs his tractor and i'm just a freebie helper neighbour, with time to spare, it's a small Village of 26 people, so I don't mind all the back and forward, and I like to fix things, whoever they belong to, we all in the same boat.


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## Biker

Trouble in paradise.

One of the hoses leading from the pump was found to leak under load.
We replaced that and the turn to the right is now better than ever.

The kingpins are not binding, free as a breeze..

We determine to take the 'control body' apart and look see / clean up since turn to the left showed poor pressure at the left cylinder, and poor turning capability.
_
We are unable to remove the control body from the base of the steering column.. This is our dilema at this stage._

We have removed the steering wheel and the dash, thinking the 'unit' would removed backwards into the cab area.. Not to be, there is a heavy metal bulkhead with just a round hole for the outer sleeve of the steering column.

It seems to be not able to go forwards because it hit the rear of the motor..

We do not know and can not see how to remove the hydraulic steering motor from the base of the steering column.

We did try to 'unscrew' the outer tube of the column, but it did not want to budge, we did not force the issue since we were not sure what would come next..

Maybe someone knows.. or has some insight or opinion.. 
Maybe I have to contact Massey direct for informtion? 

The 'unit' is held to the firewall by a bracket, we have unscrewed that from the firewall, but that just allows the whole lot to move about..
The bracket attaches to the 'control unit' by 4 bolts, also impossible looking to unscrew, from the firewall, yes, from the Unit.. not easy at all.

Were the 'steering column' attaches to the hydraulic motor/valve unit is, I would say, is impossible to get at while in the Tractor.. Is why I thought it 'must' move out as a whole unit rearwards.. 

The three of us are stumped, I said I will ask the Forum guys, and here we find ourselves..

Thanks your time and attention.


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## Biker

Hi all,
Trouble in paradise... Still not fixed and we are just about out of options.
We removed the 'Steering Valve Body' a rotary valve, cleaned it out.. there was no sign of wear and it's a pretty simple arrangement.. replacement showed no change in the No Steering situation.

We removed the back from the gear driven oil pump and cleaned the small mesh filter, which was not dirty anyway, replaced the oil with new.. No change.

We removed the pressure relief valve, or 'diverter valve' on the oil pump, basicaly a spring loaded stell ball.. it was set to full pressure, No change.

We removed both steering cylinders from their ball joints, rotaed the steering whell and they moved in and out as you waould expect, opposite to each other..
So the plumbing and operations are ok..

We dissembled a cylinder to check for wear on the piston rings or damage.. none.

We still have no Steering.. Logic seesm to indicat there is not enough pressure to do the job of turning the wheels via the cylinders..

So now we want to check the pressur from the pump, we have no tools or info so we have to muster those items..

It's been pretty frustrationg and a real good challenge so far, no complaints..
There is not much to the 'System' and you would think it pretty easy to both fatom and fix.. Only 6000 hrs on the tidy machine.

I'll post results as they come in.. If all else fails..
The owner will have to take it to a Dealer and just throw money at it.. I guess.


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## RM-MN

Biker said:


> Hi all,
> Trouble in paradise... Still not fixed and we are just about out of options.
> We removed the 'Steering Valve Body' a rotary valve, cleaned it out.. there was no sign of wear and it's a pretty simple arrangement.. replacement showed no change in the No Steering situation.
> 
> We removed the back from the gear driven oil pump and cleaned the small mesh filter, which was not dirty anyway, replaced the oil with new.. No change.
> 
> We removed the pressure relief valve, or 'diverter valve' on the oil pump, basicaly a spring loaded stell ball.. it was set to full pressure, No change.
> 
> We removed both steering cylinders from their ball joints, rotaed the steering whell and they moved in and out as you waould expect, opposite to each other..
> So the plumbing and operations are ok..
> 
> We dissembled a cylinder to check for wear on the piston rings or damage.. none.
> 
> We still have no Steering.. Logic seesm to indicat there is not enough pressure to do the job of turning the wheels via the cylinders..
> 
> So now we want to check the pressur from the pump, we have no tools or info so we have to muster those items..
> 
> It's been pretty frustrationg and a real good challenge so far, no complaints..
> There is not much to the 'System' and you would think it pretty easy to both fatom and fix.. Only 6000 hrs on the tidy machine.
> 
> I'll post results as they come in.. If all else fails..
> The owner will have to take it to a Dealer and just throw money at it.. I guess.


You may have a leak inside the steering cylinders. Without a load on them they would move just fine but under a heavy load the seal may leak so there isn't enough force left to make the wheels turn. You may be able to disassemble them and replace the seals yourself but it might be easier to let the dealer do the work because they would have the tools, the knowledge of how to attack the problem, and the parts necessary to do the repair correctly. The dealer would also be able to test the pump pressure in case that is worn out.


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## Biker

Thanks RM, Yes exactely like what you said..
We rationalised the same conclusion, 
that without load the 'cylinders' would 'appear' to work fine..

The 'problem' cylinder is now in at the Hydraulics Workshop to both 
A: Test under load
B: Fix as and if required..

Am waiting for a phone call.. I'll keep you's all posted

PS: We are thinking the 'seal' at the base of the cylinder is the issue.. maybe an o ring..
And no, we don't have the equipment to get to the bottom of the blind cylinder.. in this case we are prepared to spend, at least the owner is.. Am just a helpful neighbour.
Thanks your advice.. it's been a great problem to overcome.


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## Fedup

Piston seals? Imagine that.


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## Biker

Hang on Fedup, the jury is still out..
There'll be time enough for credits once the 
dealings done..

But yeah, you'r detailed explaination was a beauty
Maybe we should have read it more carefully us
simple folk looked for a simpler answer and all
we found was a whole heap of trouble..


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## shona13

G'day Biker .
Not sure if you fixed it yet ,if not I can send you a detailed drawing of the power steering system.


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## Michael Wolf

Biker said:


> It's my neighbours tractor, he's asked me to help out,
> I asking you the same thing.
> 'You can turn the steering wheel around and around many times to try to get some response'.. Was his description of the problem.
> It is power steering, I havn't been there yet to try it,
> but I'm the one who has to fix it., is what neighbours do..
> I don't have any idea about what it could be, yes there is oil in the pump, the belt is ok and tension ok.. No leaks or squeaks..
> yes I have good mechanical understandings, but no experience with this issue.
> Any ideas.. Thanks in advance, I'll follow through with it ok. Ian


Lid your power steering works off your trans or Hydraulic fluid it could be low. I’ve experienced the same thing with Massey Ferguson 533


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