The story continues...
ICS Steering have informed me that they have no stock at the moment.

I will continue on that front but would like your opinions on my idea above to recondition my power box, pack with grease and seal off the fluid connections. A feasible technical solution?

Dave

 

My thoughts on that idea:
No matter what you lubricate it with, the box was not meant to work without having high pressure oil running through it, you would be steering against the piston and its rings, and the friction of that.
I suppose you could take the rings out so the oil would freely flow from one side of the piston to the other, as not to add resistance to the steering _ that may even work, but oil, not grease.

The steering would feel a little vague as the wheel would still be activating the valve that controls the oil that runs to one side of the piston or the other.
You would have to find a way to lock up the valve.

The recirculating ***** was designed to run in oil, not grease.
You would have to pack it solid with grease to be sure the ***** would remain lubricated, and you would be steering against that.

 

Thanks Jeff! One thing I thought of: in case the pump fails, manual steering without support should still be possible. Hence one option could be to fill with oil and connect the fluid connections on the box together.
Dave

 

If the pump fails you can still steer the car, but it's very difficult of course, try turning the wheel while coasting down a hill around a corner _ it's quite difficult.
This is because you're now working against the oil on either side of the piston with no pressure, by turning the wheel with no pump, you're moving the oil around with just the wheel _it's very difficult.
If you try this, the power brakes won't work of course, so be aware of that, you will still have breaks until the vacuum reservoir empties, but it will take a lot of foot pressure to stop the car after the reservoir empties.

As for connecting the two oil ports together, you're breaking new ground here, I don't know if that will work, there may be a check valve involved somewhere that will keep this from working _ it may turn on one direction really well, but not so much in the other.
I also just thought of something else, none of this will work very well at all, without any high oil pressure in pipe 46 in post #9, the drop shaft will only have the spring pressure to hold it down on the worm assembly.
The drop shaft will wonder up a bit as you steer adding to the sloppy steering.

About the pump failing, I have never heard of them failing, what does happen is the drive dog coupling fails _ it's rubber mounted, and the rubber fails, and the steel drive then disintegrates working against the bare metal.

 

I've heard of people making power racks into non-power by removing the piston, connecting the hydraulic lines together and filling with power steering fluid. Doing something similar with a Burman box sounds difficult. I think I'd swap to a standard unassisted Burman system (that has to include the idler, not just the box) and wait for a high ratio box to become available.

 

Peter, Your description on conversion is exactly the idea I had. By the way, what is the idler?
Dave

 

The steering system is a bunch of links, arms and rods. It's important that they are symmetric between the left and right sides of the car. There's an arm projecting from the steering box, which if I remember right is usually called the drop arm or Pitman arm. It does the work of displacing the centre link to steer the car. There's a mirror image of the Pitman arm on the other side of the car also attached to the centre link. It's the idler arm or idler lever. The idler arm matches the Pitman (in a mirror image, geometric sense). The power steering box has its matching idler that is different from that for the non-assisted box. As a consequence, they have to be swapped in pairs.

There are other bits that may be different, but the idler is the most important for keeping the geometry right. The steering arms attached to the suspension uprights are also different in the power system, but for these, I think it's better not to swap as your PAS ones are stronger and anyway are a matched pair.

 

The Idler/drop arm is the bar that rotates on the bottom of the output spindle and moves the steering arms. They are or can be different lengths or even designs. I know the Idler arm or drop arm on the Adwest Marles Variomatic box is very curved and strengthened to account for the fact it is less turns from lock to lock and therefore needs to be stronger because of the extra force being sent through it. The Idler or drop arm on the Non PAS standard box is very long and slender which you can see in the attached diagrams. As Peter has said they come in pairs and if one is changed without the other the steering geometry would be all over the place.

This is the Non PAS steering box set up. Item 20 is the Idler / drop arm

This is the Burman PAS steering box set up. Item 33 is the Idler/ drop arm.

This is the Variomatic PAS steering box set up. Item 33 is the Idler/ drop arm.

 

All the explanation is in what Cass and I have written, but it may be as clear as mud. Very simply the Pitman or drop arm is attached to the steering box and does the work; the idler is on the other side of the car, is a mirror image of the drop arm and follows the motion of the centre link. I guess it sort of idles along 🤔?

​​​​​https://www.freeasestudyguides.com/i...g-linkage.html

The picture in the link might help.

 

Idler arm ~ opposite steering box arm. Left hand drive car.

 

Thanks for the explanations. I‘ve also been reading other threads on steering options. It seems that the option with keeping the electrical steering and changing to a manual box would run the risk of having components which are sensitive to being distorted. Is that correct? It also raises the question whether the ICS version would also be similarly sensitive...
Dave

 

The strength requirement is mainly for the steering arms (the arms attached to the suspension uprights - or hub carriers in old Jaguar terminology) and that's if you've parked with the wheels next to a kerb and try to turn the wheel. The steering box should be fine as several owners have used them with Burman boxes (and with non-PAS steering arms). You can always check with ICS.

 

The pic I show above are the beefed up power steering arms. Manual steering arms are weedy by comparison & will bend if turned against a curb as Peter says.

These are the weedy non PAS arms.

 

Dave this should not be a problem for you as you already have the PAS steering linkages which are the beefed up ones that Glyn has shown in #30 so as long as you retain these and transfer the beefed up steering arm from the PAS box you have to the non PAS box you intend buying it will be fine. I would assume that the splines and diameter of the spindle are the same but I have no way of checking.

 

Dear All,
I’m wondering again whether to start this project and would like to hear your opinions…
The previous owner fitted the electrical steering and I don’t have any information how it was done, hence the motivation for the following question.

Is it possible to remove the steering box and the lower steering column without touching the upper steering column? I see the chance using the ‘flexibility’ provided by the 2 universal joints.

Regards,
Dave

PS Are there preferences that I should start a new thread?