I recently acquired a 1962 Mark II 3.8 automatic that was extensively restored about twenty years ago and is still in pretty good shape, except for the steering. The steering on the car was very loose, to the extent of drifting all over the road. My restoration shop that does work on cars not primarily Jaguars sent the steering box out to a rebuilder in California. When it was returned it was a little better but still not tight. The rebuilder sent another box, with only slightly better results. After speaking with a jaguar specialist shop in the area I was told that you can't successfully rebuild a power steering box because the parts are not available any longer and that the only solution is to convert to a rack and pinion system at an estimated cost of $10,000.00. I have been trying to get information in order to make an informed decision before making this additional investment. Some things I have read say that a rack system conversion is not a good idea and can make even the situation worse.

My hope is that someone in the group has had a similar problem and can share some feedback on the two questions: Is it true that the original box can't be successfully repaired and, if not, what are the alternatives? Is a rack conversion the way to go? Thanks for the anticipated replies. I love this car and want to get the best driving experience available from it.

 

others here know a lot more about this issue but what I know is that you can fit a steering box from a Jaguar 420, or maybe better yet, fit a complete front suspension member from a 420 with the improved box.

The rack and pinion system from a Jaguar XJ-6 doesn't work in these Small Saloon cars. Waste of money. Ruins the geometry they say.

 

Thanks. I wonder if anyone has hd experience with the rack system sold by S.M. Barrett.

 

The box may not be the culprit. There are rubber bushings in the linkage and those perish with age, giving the symptoms of wander. I'd make sure that all the linkage is is perfect shape before looking at the box. Once that is checked over, then get a wheel alignment and make sure the caster is correct. It can be difficult to get enough of an angle in these cars to give modern levels of straight tracking.

The parts that perish are called the draglinks, and they are the pin and bush that is on the end of the steering arm and the idler arm that attach to the centre track rod. Replacements are available that remove the rubber. Part number is C29094 and C29095 for the entire assembly, the pin and bush replacement is here:

https://www.sngbarratt.com/English/#...e-8a6db2eb9db3

 

I endorse Jagboi's recommendations.
In addition, I suggest the whole front end is inspected carefully as the previous restoration of 20 years ago may be decaying.
EG I have seen polyurethane bushings used in place of rubber bushings falling apart. Even rubber bushings at 20 years of age are getting a bit suspect.
Until the whole front end and suspension is proven to be in good shape it is no good blaming the steering box.

 

I treble the above. The main problem with the older steering box set up is there are so many links and joints from the steering wheel bushes down through the column to the box where you have the U/J to the ends of each steering arm with its many joints. If each joint only had 1/16 (1.5mm) of wear then across the whole system you could be looking at about 1/2 an inch (12mm) of play. Add to this cross ply tyres and worn wheel bearings and you could be having to be constantly putting movement into the steering wheel to keep the car straight. I would start by replacing all the joints on the steering arms and steering column along with the top and bottom suspension bushes, you will be amazed at the difference that can make.
As Jose has stated changing to the later Adwest Marles PAS box from the 420 which was also fitted to the later 240, 340 and S Type from 1967 onward is a better choice than going for such a radical change to rack and pinion and all the variables plus cost involved. You would need the complete front subframe from the donor car which has a cut out to accommodate the larger Adwest steering box but your original Steering pump and reservoir is the same as my S Type and can be used. The 420 had a different pump set up. Having said that even if you got a 420 subframe and Adwest steering box which is a vast improvement over the Burman I would still renew all the steering linkages and bushes to get that tighter feel.
As for rebuilding the PAS box I have not done a Burman box (I have rebuilt my Adwest Marles on my 1967 S type which is completely different ) but as I understand it there are people who can rebuild the Burman box with new parts and most of the slack/wear can be taken up with adding extra shims. (The Adwest has adjuster screws for this purpose).

 

Here's another endorsement for JB and Bill.

The early PAS system is low geared and doesn't use a good method for controlling the level of assistance. All the later boxes are better. Steering boxes are too often condemned out of hand. Some very successful Ferrari, Alfa, BMW, and Mercedes have used them. For wear resistance, the Burman and especially the Marles Adwest boxes used by Jaguar are generally better than racks. With correct maintenance they can survive close to for ever!

There are volumes of discussions on rack conversions in this forum. Opinions differ considerably. I can't say that my own have not oscillated over the years. I've laid out an XJ rack next to a Mk2 subframe on my garage floor together with brackets that I made up. It looked very awkward - basically the tie rods end up very short compared to the lower wishbones. If I converted to a rack, I'd want to modify the position of the steering arms on the front uprights, moving them in to recover Ackerman, and stiffen the suspension to limit bump steer. That's extra work and not included in the rather high $10,000 estimate. (That cost could be reduced by finding all the parts separately rather than going for a kit.)

So, first follow JB and Bill and check/restore the whole front subframe. Perhaps check the bushes to the rear axle as well. When that's all done, if you still don't like the steering consider a later S type or 420 steering box before going to a rack. For the 420, you might take the whole subframe.

 

Also the vehicle might well have been fitted with the later engine compartment column due to play issues.

There is a plunging CV joint at the top of this shaft & a UJ at the steering box. The CV joint has 2 nylon rollers in it that wear. This can cause what you describe & they are readily available. Replace them with a new boot & pack with a 3 to 5% moly grease. Only 2 circlips & boot to remove plus loosening the clamp at the base of the column & pulling the column off the splines. Try and preserve the boot clamps that are long out of production. Otherwise zip ties work just as well on the boot.





Worn mess that has been fouling

 

Another thing to consider is subframe mounts front and back. If you have old spongy worn subframe mounts and rear radius arm bushes you might even be getting a little unwanted steering from the back axle.