Dismantling rack contol valve

[Stagdad]

Looking to fit the seals Ian (Milo) very kindly gave me.

I'm after a bit of guidance as to how the control valve comes apart ,It looked to me that after the circlip was removed above the oil seal in the picture below the guts of it would come out from the top but they won't .So I then removed the unit and at the other end is a circlip to retain the bearing ,on removing this circlip I thought the shaft would then tap upwards ,again no:?.The rom is very sketchy on this and there are no pics of which way the inards should be coming out.

It simply says "Carefully press or tap out the pinion shaft andwithdraw the spool sleeve and pinion assembly from the housing" But from which end ????????

I'm normaly pretty good at working out whats going on but this one has got me puzzled and I don't want to damage it .

Thanks in advance Steve

[DJT]

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Hi Steve,

It is a while since I did this job, but.......

If you look at the cutaway drawing in section 57.00.05 of the ROM, you will see that the pinion shaft is not too dissimilar to a water pump in its overall appearance. This drawing indicates that the shaft is tapped downwards to exit the valve at the bottom.

Be careful with the white seal rings on the pinion. I actually changed them on the previous one I did, but panicked when they wouldn't sit properly in their slots. I eventually got them to shrink back to size and rebuilt the valve, but I was worried I had messed up, especially when you read the warnings in the ROM. I don't think Iwill bother to disturb them when I do another rack later this month.

Dave

[les M]

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Steve

Dave is correct in that the shaft and spool can be pushed out. see attached drawing.

Les.


Steve when you put it back together and make sure you get the spool and the torque tube correctly aligned, section 57 of the rom should have the drawings for the spool assembly and porting arrangements.

[Stagdad]

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Thanks Guys ,so just to clarify i'm looking to tap/press on the tortion bar Item 1 in the drawing to push everything out at the bottom.Yes?


And is it with or without pin 25 fitted when I do the pushing?


Cheers Steve

[milothedog]

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When I repaired my spare rack I just used the seals etc for the ram assembly which was leaking at both ends, hence having the parts spare that Steve needs. When I removed the control valve there wasn't any sign of the slightest leak so I repacked the bearings and refitted it I suspect I have the same problem as Steve (A worn roll pin)with the rack on the car at the moment i.e. a small amount of annoying free play which is in the rack but not the inner ball joints or pinion meshing wear.

Best of luck with it Steve.

Ian.

[Stagdad]

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Thank Ian ,If I could change the top oil seal without striping it I would as I don't like the idea ofputting it back together wrong but also it does have signs of slight oil around the bottom bearing so worth doing if I don't balls it up:shock:.

Cheers Steve

[DJT]

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Stagdad wrote:

Thanks Guys ,so just to clarify i'm looking to tap/press on the tortion bar Item 1 in the drawing to push everything out at the bottom.Yes?


And is it with or without pin 25 fitted when I do the pushing?


Cheers Steve

IIRC I didn't remove the pin, so the whole lot must have come out together.

Dave

[Stagdad]

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DJT wrote:

Stagdad wrote:

Thanks Guys ,so just to clarify i'm looking to tap/press on the tortion bar Item 1 in the drawing to push everything out at the bottom.Yes?


And is it with or without pin 25 fitted when I do the pushing?


Cheers Steve

IIRC I didn't remove the pin, so the whole lot must have come out together.

Dave

Thats what I did Dave and it came out first tap,all sorted and ready to refit on the car.Once again thanks to everyone for their help. Power of the forum rules

Cheers Steve

[jpyke]

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When I get some time (hopefully this year) I'm planning to have a new torsion bar made which is slightly thicker (I think I mentioned this before). I've got the original engineering drawings for the part, together with the material and harness specs. and the calculations to increase stiffness by X%.

I'm hoping to get a little more feel back into the steering by removing some of the power assistance. It's tricky to know how much to go for without having several made of different thicknesses to try out (probably expensive) so I think I'm gonna start with 20% and see how it goes.

[Stagdad]

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jpyke wrote:

When I get some time (hopefully this year) I'm planning to have a new torsion bar made which is slightly thicker (I think I mentioned this before). I've got the original engineering drawings for the part, together with the material and harness specs. and the calculations to increase stiffness by X%.

I'm hoping to get a little more feel back into the steering by removing some of the power assistance. It's tricky to know how much to go for without having several made of different thicknesses to try out (probably expensive) so I think I'm gonna start with 20% and see how it goes.

Let us know your findings,for me it will make a changefor the steering wheel to actually do something:?.

Cheers Steve

[jpyke]

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Indeed I will

Right now I'm worried about the roll pins that pin the torsion bar top and bottom. These effectively transmit any of the manual feel from the rack, through the torsion bar and into the steering column. Any looseness in these allows the spool valve to turn without turning the torsion bar and this has the effect of applying power assistance with no manual assistance until you move the wheel enough to get past the looseness. A stiffer torsion bar is only going to put more pressure on these pins and I worry that they'll get loose quite quickly.

I believe vmad found some hardened steel replacements rather than roll pins which he used with success.

One note of caution regarding your fixes to the spool valve... there are O-rings on the torsion bar at the top and bottom which prevent hydraulic fluid leaking into the rack at the bottom and out of the top of the splined shaft at the top. Not sure if you replaced these? Dunno if a leak could be due to these that's all.

[Stagdad]

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jpyke wrote:

Indeed I will

Right now I'm worried about the roll pins that pin the torsion bar top and bottom. These effectively transmit any of the manual feel from the rack, through the torsion bar and into the steering column. Any looseness in these allows the spool valve to turn without turning the torsion bar and this has the effect of applying power assistance with no manual assistance until you move the wheel enough to get past the looseness. A stiffer torsion bar is only going to put more pressure on these pins and I worry that they'll get loose quite quickly.

I believe vmad found some hardened steel replacements rather than roll pins which he used with success.

One note of caution regarding your fixes to the spool valve... there are O-rings on the torsion bar at the top and bottom which prevent hydraulic fluid leaking into the rack at the bottom and out of the top of the splined shaft at the top. Not sure if you replaced these? Dunno if a leak could be due to these that's all.

I sorted the roll pin by drilling with oversize drill bit and then using the plane part of the drill bitas the pin,seems perfect at the moment and should be quite hard.I changed the seals top and bottem whichappeared to be the only way out for the fluid .

Cheers Steve