Lotus Elan

Snapped Steering Column

PostPost by: Craig Elliott » Sat Nov 08, 2003 10:58 am

I recently had the steering column snap on my '73 Elan +2 130/5 while I was pulling out from a parking space. This left me with no steering.

The car has the collapsable type of steering column and the upper part of the column snapped right by the clamp that links it to the lower half. Where the column snapped the metal looks chrystalline (i.e. as if it is a fatigue fracture) and I'm trying to work out what caused the problem as I don't want it to happen again. Has anyone else had this happen?

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PostPost by: LaikaTheDog » Sat Nov 08, 2003 1:33 pm

when you say 'crystalline', I guess you mean the internal make up at this point, rather than the surface ?. Looking at the manual this section actually has a rebate cut in mine, I had always figured that this was because it is the intended break point for the column in the event of an accident. They are meant to snap easily, therefore I would expect the composition of the metal at this point to be weaker, however not weak enough for parking torques to cause the break....
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PostPost by: Craig Elliott » Sat Nov 08, 2003 1:50 pm

Yes, you're right I do mean the "internal" structure of the metal - and it did break where the cutout is. However, I don't think these are meant to break in the event of an accident, from the manual drawings it looks as though the idea is that the lower part of the column slides up inside the upper reducing the chances of the steering wheel hitting you in the face.

I guess one cause could have been a slight mis-alignment of the upper and lower parts of the column which, over the years, could have been generating stress/slight flexing.

Post script to the above - having now replaced the upper half of the column and retrieved the bottom part of the broken section, it definately looks like this was a stress fracture that built up over time until it snapped...
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PostPost by: gobw2 » Mon Nov 10, 2003 4:04 am

:o Yes, it seems to be a fatigue fracture, but if the misalignment was severe enough to flex the coll, I would think you would have felt the resistance, and from what others have said, Doubt the coll bearings are that robust - should have worn out, thus relieving the stress. George
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PostPost by: HARVEYW » Tue Nov 11, 2003 1:19 pm

Hi! Had this happen to me a couple of years ago, again thankfully in a car park. The problem is more likely to happen at parking speeds because there is more stress going through the mechanicals at slower speed. Mick Millar repaired it, and commented that this was a common fault. A replacement column should not be over tightening when reconnecting. Modern tyres are stickier than those made in the '60s thus increasing load on the column - this part is after all sourced from a Trumph Herald.

Stay safe

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PostPost by: tdafforn » Tue Nov 11, 2003 2:48 pm

During a past life when I owned a triumph spitfire (same steering column) when I also subscribed to an Autox.net group the frailty of the column at this point was a common topic. It was never solved and was only observed at low speeds (along with the vertical link snapping!). Worth looking at the archives..
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