Rack dampers

[les]

I’ve been puzzled by a rattle from the steering, when going over even a smallish bump or pothole. It’s just dawned on me that there are two brass dampers in the rack itself, and consider this to be a good starting point in curing this rattle, can anyone suggest any other possibilities ? ———-Also I imagine these said dampers have an associated spring to provide pressure, can anyone confirm this please ?

[philthehill]

Les
Happy New Year to you.
There are springs Pt No: 183906 under the hexagon cap Pt No: 183905 pressing down on pad Pt No: 183904. There is a fibre washer Pt No: 183903 and packing washer Pt No: 184002. I do not know how much adjustment you can make other than make sure that the spring has sufficient compression to press hard against the rack.
See Section J.10 of the BMC wksp man for further details.
Phil

[Peted7202]

There are two damper pads on the steering rack available from ESM. They are not adjustable. If you remove them the pads will probably have a curved wear pattern where they press on to the shaft. The new ones will be flat and will therefore take up any play. Simply refit and tighten.
I would also check for any other reason for the rattle. Play in joints, steering column and clamp bolt.

[les]

Thanks for all that info Phil, it will be useful to me, and Happy New year to you too ——and to Peted7202, I presume it’s Pete !
ESM have one of the damper bushes but not the other, for the foreseeable future. I’ll try elsewhere, maybe Moss will have some.
I have two spare racks, so if I have no luck, I’ll check the condition of their dampers. Thanks for prompt response.

[Andy999]

Couldn't find anyone with stock of the larger dampers so had the local machine shop make one from phospher bronze. Steering rack nice and tight now but my rattle turned out to be wear on the torsion bar splines....
No-one seems to have new torsion bars so rummaged through lots of secondhand ones until I found a "good" bar - problem solved!

[les]

Thanks for that, hadn’t thought of the splines. I too can’t find a supplier of the main damper, or indeed the secondary damper spring. I’ll be checking a couple of spare racks to see if the dampers etc are serviceable.

[oliver90owner]

If springs have lost some of their tension/length, I have sometimes resorted to shimming. Would it not be appropriate for this application?

[les]

Shims are part of the setup, however there is a procedure to follow regarding the pressure on the damper. Removing shim/shims would help with spring tension. I need to compare a new spring length with old.

[les]

As an update, no luck finding the large damper as suspected, although I have the associated new spring for it. I also have a new secondary damper and the secondary spring in my spare racks appears good, however the dampers are shot. So I’m now left wanting the large damper. I may well have to get one made like Andy. I’m pretty sure I’ve got the bronze bar.
Incidentally if anyone has the chance to measure the gap between the top of the tyre and bottom of the front wing, I’d be pleased to know, my N/S is about 2 inches, the O/S about 3 1/2 inches. (I appreciate different tyres will have a bearing on this but it will give me an idea ) I need to adjust one side. I’ve checked the lower arm positions and suspect the O/S is too high. Thanks.

[Sleeper]

What are the measurements with a driver seated?

John ;-)

[les]

To be honest John, I haven’t looked at that. However when setting up, the suspension is set so each side is the same level, ignoring the weight of the driver.

[les]

I’m not going to play with the ride height at the moment, in fact the difference between each side does not appear as great as first thought. So tomorrow the priority is to find a reputable company to make the main damper, and hopefully cure the steering rattle. I may fit the secondary damper first, in fact that one alone, might be the culprit.
I was surprised to read as much as 1/2pint of oil is needed for the rack, I hope to do this via one of the damper holes, rather than the nipple.

[les]

Replaced rack dampers, what a difference! Both main and secondary were badly worn and I was shocked to find the secondary damper cap about 3 threads undone, and the main one finger tight. What a game replacing them. Picture of main damper ———-

66E6C7BD-82E6-457A-8EC0-A7D2154860A6.jpeg (1.57 MiB) Viewed 970 times

[philthehill]

Les
Well done.
Did you use good S/H items or had them made?
Phil

[les]

Hello Phil, the secondary damper and spring for the main damper I bought from ESM. No stock for the main damper, like everywhere else I tried. However I fortunately had some bronze bar and a local engineering company made one for me, they copied the original perfectly, which really pleased me. One or two more jobs to do and the van should be a pleasure to drive once more. I’m not keen on working on these cold days, so hoping for warmer times!

[philthehill]

Les
Many thanks for the update.
That engineering firm sounds like a good firm to know. Not many firms these days would do a one off job such as your damper pad.
Phil

[les]

That’s true, it’s a two man setup with a variety of tools/machinery. Old school, I suppose you’d describe it. The damper was spot on.