Steering Rack Help
Discussion
Can anyone help with a question on the steering rack pinion.
I have removed the pinion from the steering rack - primarily to get rid of all the rust on the pinion splines and replace the seals/circlip .
The picture of the pinion shows a machined dog and groove which suggests that the bit with the 4 white washers should rotate a few degrees about the centre of the pinion. Further evidence of this in julian64' post quoted below.
"There is a very thin shaft that runs down the centre of the steering shaft. As you turn the wheel fractionally in either direction the twisting of this shaft opens a set of holes. With the engine on this allows pumped oil to gush through the holes and push on the steering rack screw plates.
Without the engine on, the shaft simply twists till it hits a stop, and then the major shaft of the steering takes the weight of moving the wheels."
Should this machined collar with the holes and washers be free to rotate about the centre shaft of the pinion?
I'm hoping the answer is no.
I have removed the pinion from the steering rack - primarily to get rid of all the rust on the pinion splines and replace the seals/circlip .
The picture of the pinion shows a machined dog and groove which suggests that the bit with the 4 white washers should rotate a few degrees about the centre of the pinion. Further evidence of this in julian64' post quoted below.
"There is a very thin shaft that runs down the centre of the steering shaft. As you turn the wheel fractionally in either direction the twisting of this shaft opens a set of holes. With the engine on this allows pumped oil to gush through the holes and push on the steering rack screw plates.
Without the engine on, the shaft simply twists till it hits a stop, and then the major shaft of the steering takes the weight of moving the wheels."
Should this machined collar with the holes and washers be free to rotate about the centre shaft of the pinion?
I'm hoping the answer is no.
Edited by mikesr on Friday 28th December 13:10
I've not taken my rack to pieces, but looking at your picture, if the top half (with the washers on) turns in relation to the lower (pinion) half of the shaft, the steering won't turn the wheels, the steering wheel will just spin round because the steering wheel is attached to the centre shaft, which, if the engine isn't running, physically pushes the steered wheels, via the stops you've arrowed. If the top isn't attached to the bottom it hasn't anything to turn, all it would be is a fluid valve.
To direct oil, when the engine is running, the valve is twisted and allows oil pressure into the rack rams to assist the pinion in turning the wheels, when the steering is not being turned, the valve returns to the centre and stops fluid flow.
I hope that all makes sense!!?
To direct oil, when the engine is running, the valve is twisted and allows oil pressure into the rack rams to assist the pinion in turning the wheels, when the steering is not being turned, the valve returns to the centre and stops fluid flow.
I hope that all makes sense!!?
Thanks for the comments. I've been examining it again to try to sort out how it works.
The splined end and the pinion appear to be connected by a thin rod that is held by a machine pin at each end. The one on the pinion is visible in the picture. The pinion ends before the two metal disks and thin washer. The disks are bearing cups.
The bit with the white washers starts after the bearing.
What I can't work out is how the holes get exposed to allow the fluid through.
I thought at first the bit with the white washers rotated between the stops around the central pin. But it doesn't move at all.
I guess its possible there is a sleeve inside the bit with the washers that rotates to expose the holes.
I'll have another look at it tomorrow.
The splined end and the pinion appear to be connected by a thin rod that is held by a machine pin at each end. The one on the pinion is visible in the picture. The pinion ends before the two metal disks and thin washer. The disks are bearing cups.
The bit with the white washers starts after the bearing.
What I can't work out is how the holes get exposed to allow the fluid through.
I thought at first the bit with the white washers rotated between the stops around the central pin. But it doesn't move at all.
I guess its possible there is a sleeve inside the bit with the washers that rotates to expose the holes.
I'll have another look at it tomorrow.
I'm pretty sure you are correct.
I was expecting to see something turning under hand pressure but I suspect under the loads exerted when its in the rack on the car the centre turns with respect to the outer bit with the white washers - thus exposing the relevant holes.
The rack isn't leaking - it was just very rusty on the pinion. So I think I'm being paranoid and looking for problems.
Cleaning the rust from the circlip groove that sits above the outer seal and replacing the inner and outer pinion seals should be all thats needed.
Thanks for the help.
I should stick to messing with the ECU software - all this mechanical stuff addles my brain
I was expecting to see something turning under hand pressure but I suspect under the loads exerted when its in the rack on the car the centre turns with respect to the outer bit with the white washers - thus exposing the relevant holes.
The rack isn't leaking - it was just very rusty on the pinion. So I think I'm being paranoid and looking for problems.
Cleaning the rust from the circlip groove that sits above the outer seal and replacing the inner and outer pinion seals should be all thats needed.
Thanks for the help.
I should stick to messing with the ECU software - all this mechanical stuff addles my brain
No the answer is no to your initial question. It isn't free, it does rotate though due to the torsion in the long shaft, and completely hits the stop on both sides which is how you can steer the car with the engine off.
Two years since I took mine apart. The biggest problem I remember was finding someone who did all the rubber seals. To my disgrace I left two of the originals in after not being able to source them.
A job I keep meaning to go back to at some point, so would be interested if you've found a supply
Two years since I took mine apart. The biggest problem I remember was finding someone who did all the rubber seals. To my disgrace I left two of the originals in after not being able to source them.
A job I keep meaning to go back to at some point, so would be interested if you've found a supply
Hi Julian, did you strip the entire rack?
I haven't, although that was the original intention because the rack felt quite stiff and notchy, I've just taken the pinion out.
There are no fluid leaks and the gaiters are intact and everything underneath them is shiny and greasy.
So I'm hoping to get away with just replacing the inner and outer pinion seals. The alternate parts spreadsheet suggests they are available from BSL.
However, if it all goes pear shaped SI-PEN seems to have sourced the seals from Greenwich Power Steering as per this thread
Having removed the tensioner thing (Burrmann adjuster is it?) the rack is now smooth and slidey as it should be. So I suspect even with the adjuster grub screw backed off the tension was too great. So I'll have to do something to relieve it (probably a spacer under the covering plate) so that the adjuster screw is usable.
And there was me thinking it was just UJs seized up
I haven't, although that was the original intention because the rack felt quite stiff and notchy, I've just taken the pinion out.
There are no fluid leaks and the gaiters are intact and everything underneath them is shiny and greasy.
So I'm hoping to get away with just replacing the inner and outer pinion seals. The alternate parts spreadsheet suggests they are available from BSL.
However, if it all goes pear shaped SI-PEN seems to have sourced the seals from Greenwich Power Steering as per this thread
Having removed the tensioner thing (Burrmann adjuster is it?) the rack is now smooth and slidey as it should be. So I suspect even with the adjuster grub screw backed off the tension was too great. So I'll have to do something to relieve it (probably a spacer under the covering plate) so that the adjuster screw is usable.
And there was me thinking it was just UJs seized up
Yep, but although the power steering fluid was a horrible mud inside the rack, the rack itself looked in great shape.
That tension bolt on the top was a tricky thing because for a long time I thought it was my problem (inch of play at the wheel before anything moved).
But mine turned out to be that little machine pin had worn away part of the quill hole and was then a sloppy fit.
That tension bolt on the top was a tricky thing because for a long time I thought it was my problem (inch of play at the wheel before anything moved).
But mine turned out to be that little machine pin had worn away part of the quill hole and was then a sloppy fit.
Did the track rods unscrew easily?
I'm assuming with the pinion in place the pinion gear will prevent the rack from turning so that the track rods can be undone.
The N/S rod end just won't budge so I think it will have to be a blow torch and stilson job which I'd rather do with the track rod off the rack.
And if I can't get it to shift I can just replace the rod and rod end.
I'm assuming with the pinion in place the pinion gear will prevent the rack from turning so that the track rods can be undone.
The N/S rod end just won't budge so I think it will have to be a blow torch and stilson job which I'd rather do with the track rod off the rack.
And if I can't get it to shift I can just replace the rod and rod end.
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