Fifteen steering box 1934

[Petelang]

Can any of the Fifteen boffins please tell me what make and type of steering box is fitted?
Is it Burman, Douglas Burman or some other make?
Is there a trusted supplier that anyone has used to restore one?
What can be done to reduce a bit of play within?

[Marcel Renshaw]

I think it’s possibly a Marles.
David Cornwallis is the supplier/ rebuilder for Marles but I am told his prices are based on the Aston Martin ones that he also does.

[ranald]

You could try Holman Engineering Co, Addleston https://www.holman-engineering.co.uk/au ... eering.php
Jeff Holman did some work on my Bishopsgear box recently. Regards, Ranald

[HenryC]

If it is a Burman Douglas steering box, that name is cast in raised letters on the outside of the main casting.

As Ranald mentions, Holman Engineering should be able to help. I visited Jeff last Monday with some success, for my EL24 box.

[Rolf B.]

Hello Pete,

my very early 1933 Daimler 15 has a Marles-Weller steering box. As Marcel wrote there's David Cornwallis who cares about these steering types

www.marlessteeringbox.com

as well as Jeff Holman.

Cheers Rolf

[Petelang]

Just an update, and thank you to those who replied.
Rolf you were absolutely correct, it is a Marles Weller box and I have now removed it, stripped it and started looking for solutions to fix it.
I spoke to David Cornwalis, I have since had to take some antidepressants, as it was not a reassuring conversation and his offered solution was a new made box at over £3300!
Apparently no parts are available, no-one in their right mind would even consider repairing one and to do so is complete folly! (Darned good sales pitch for his new product).
As ever, research is the key and despite there being very little information on the Internet I have discovered we share this problem with MG owners on early models, some of which had a small Marles Weller fitted. Now MG Owners are robust in seeking solutions and it seems many avenues have been explored from modifying VW camper steering boxes to other versions and some have attempted repairs to existing.
The essence of the problem is two fold: 1. There are four 9/32 ball bearings which sit in half cups of a floating pin which have been ground into hemisheres, which take the steering loads in contact with the worm screw.
2. The worm screw is designed to have minimal play in the centre Position of the steering yet it is the part to wear the most. Determining this wear is difficult.

As a solution it seems oversize hemispheres were made available but the danger here is that they might accommodate the wear in the central part of the worm but lock up on the further part of the worm, a potentially dangerous situation. Experience from our esteemed East Midlands club members suggest that some, in the past, have ground new hemisheres using rudimentary tooling but considering the tolerances we are working to here I don't feel I would live long enough to see a result of so much trial and error!
The wear of the hemispheres, from what I can establish is exceedingly small, original size (dome to flat) being 0.1445" where mine are at 0.141" to 0.143". So a loss of 2-3 thou has resulted in a drop arm play of some 8mm (felt at the steering wheel periphery at about 5". Of course this does not take account of possible wear on the worm screw which I cannot establish as, so far, I have not found a drawing. But I have found a 1932 drawing for the hemisheres originally made by Adamant Engineering for Marles.
My next step is looking at engineers who might be able to make some replacements to OE size at least to reduce the wear, if not to make the steering 'as new' but just manageable.
Another option is to possibly hard chrome plate the pin or the hemispheres to regain lost material?

Hemispheres 1

A spare box would have been nice as the car is disabled meantime and needed back in action before long so I'm still looking if anyone has one in the shed..?
If any of you have tackled this before I would appreciate input.

[Petelang]

Photo of the bits.

[marchesmark]

Henry,

I'd be interested in hearing some more about what Holman did for your EL24 box - mine is getting a bit loose and will need some work soon. I suspect a new bronze nut will be required, although I believe the box can be white metalled to remove wear and slop. What did you have done?

Mark

[HenryC]

Hi Mark,

The box is with Holman at the moment, the brass nut is being replaced (at considerable cost!), and the output shaft bushes are being remade. As with other steering boxes, the wear is concentrated in the middle of the worm and the new nut is fed onto the (unworn) end of the shaft. So if the shaft is badly worn in the middle, there is still going to be some play - not a perfect solution.

For info: It is a 4 start thread and appears to be shared with a Triumph model, although the nut appears to be a different size.

If you are interested, I do have a spare steering box with the adjustable column, as fitted to the saloons, I believe. It appears to have little wear but it is hard to tell, off the car. The Limousine is fitted with a shorter fixed column.

[marchesmark]

Hi Henry,

Yes I'd be interested in the spare one - would be helpful to examine it and dismantle it before I take the car off the road. Can you PM me with some pics and a price?

thanks

Mark