Dear All,
I've recently put my car through it's mot and passed with flying colours. All was well, then on a cold morning my front o/s suspension coil broke off and lay there on the road! I've read some of the discussions and this appears not as uncommon as I would have thought. On closer inspection the coil seems to have rusted and obviously this contributed heavily to its weakness.
My main concern is that this was not discovered a little while ago by the Vauxhall service & mot team - is this something that should be picked up on? If so, is there some legal comeback?
I can still drive the car with no obvious affect at present and would like to drive it the 100miles home, for my brother to fit a new coil. Anyone experienced this, and would it cause more damage to do so?
Thanks.
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The MOT only looks at specific items, and the certificate only applies on the day it was issued. It is not a guarantee of long-term reliability. Have a browse through the MOT Testers Manual for more information. tinyurl.com/2nxrmn
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I've had two springs break.
I keep an eye on my car and there was no prior warning. I very much doubt that it could be anticipated at an MOT. If you wanted all cars to fail just because their springs have rust on them then there would be no cars on teh road over three years old.
Blame the councils and their speed bumps instead.
edit: if you mean PART of the spring lay in the road, then it may be possible to drive it. It wasn't in both my cases as the spring dropped off the support. I don't think I'd risk a 100 mile drive though.
Edited by martint123 on 05/12/2008 at 10:34
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Thanks for the replies. Fair comment re: the mot.
Yes it is just part of the spring, approx. 1 rotation of the coil. There is minimal difference in the level across the car, but what the coil would be bearing onto without the first part is slightly worrying.
I do blame the councils and especially the speed bumps that serve no purpose!
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Make a very careful visual inspection on a ramp before you undertake your journey. If the spring is unstable or a sharp end of it is close to a tyre, you could have a bad accident and endanger others.
659.
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Coil springs almost always break at the point the coil just leaves the plate/cup it sits in... and this is usually about one coils rotation or a bit less. They are often rusty in that area because the coil seat traps dirt/moisture. However I believe the coil breaks there as it is the first point the coil flexes after the bit that is supported in the "cup". The breaks always look like stress fractures. The cold morning could be an issue here making the steel more brittle.
David
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>>If so, is there some legal comeback?
Errr, well. You, mean compensation? For what, exactly.
They could have insisted you have your spring replaced there and then (make you trailer the car away as not roadworthy, or else pay them to do it).
Now you're going to get your brother to do it. Bargain!
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Vauxhall coils are a joke. They are known to fail prematurely on most of their models.
Shocking really as its extremely dangerous at anything other than parking speeds.
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Vauxhall coils are a joke. They are known to fail prematurely on most of their models.
Not exclusively limited to Vauxhall. Ford, Citreon, Peugeot, to name but a few also suffer the same problems.
Tempting fate now, but in the 23 yrs I have owned Vauxhalls, I haven't yet suffered a spring failure. Nor have other family members who own/drive Vauxhalls.
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>I haven't yet suffered a spring failure ...
or anything else worse than a clutch cable. But a friend was driving away from Liverpool airport and hit a pothole in the Speke estate, which fractured the rear torsion bar on his 405. Being a sanguine individual he drove on in a lopsided manner for about 15 miles, then got piggy-backed home to Carlisle.
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Not exclusively limited to Vauxhall. Ford Citreon Peugeot to name but a few also suffer the same problems.
And Audi - I lost the bottom few centimetres a few weeks ago - and I've read of BMWs on this site somewhere, and as a regular cyclist I occasionally see a bit of a coil by the side of the road.
Seems to be a more common problem now - they are either underengineering the coils [too thin] or they have altered the way in which they locate in the cup so they fatigue fracture just above. Is there a spring factory churning out duds?
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Cars last long now, so that might be a factor. Also there is more pot holes these days, the weather seems to be wetter (more salt) and of course the stress of speed bumps.
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>>they are either underengineering the coils [too thin]
It doesn't work quite like that - if you make the coils thicker, you'll increase the rate of the spring, and, other things being equal, for a given suspension deflection, there would be more stress in the steel - hence a lower fatigue life.
Taking a few liberties with the niceties of fatigue theory, the fatigue life of steel parts with a finite fatigue life is inversley proprtional to stress cubed - even a small increase in stress is bad news! This is also why traversing potholes at speed is bad for the fatigue life of the spring.
Corrosion also speeds up the fatigue process significantly, especially if corrosion products act to wedge the crack faces open.
Incidentally, the for a given suspension deflection isn't an unrealistic proviso, for, despite that a stiffer spring will result in less suspension travel for long period disturbances, when a vehicle goes over a sudden bump, the body doesn't react, and continues in a straight line for a short time, and the bump acts to impose a fixed deflection on the suspension.
The best way to reduce stress would be to make the spring longer, with more active coils (at the expense of some unsprung mass increase - v. bad!), and a more expensive solution is to flatten the end coils.
As noted, it's difficult to design coil end detail which doesn't also act as a trap, but, in that regard, designs which avoid an upturned cup structure which traps road silt, salt, and carp are better in this regard.
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>>is this something that should be picked up on?
Until it breaks, there's nothing to see, so, I don't think there has been negligent servicing or inspection in this regard.
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The only way you could check the damage would be to remove it and use some kind of NDT technique, which would cost more than just replacing with new.
en.wikipedia.org/wiki/Nondestructive_testing#Metho...s
The alternative would be to life it, like a cambelt, but that would involve replacing all of them at about 30% of MTBF.
If you want total safety you'd have to treat your car like an aircraft - and it then would cost about twenty times as much to own/run...
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I would imagine about 50% of cars over 3 years old will have a warn suspension, it is called use ajd as oldnotbold we can't treat our cars like an aircraft, we did we would be replacing coils every year, shocks every two years, bulbs every 2 months etc etc.
The MOT has done nothing wrong here, a coil either works or it dosn't. If you took a car to the MOT and they passed it, and then both brake lights failed afterwards would you blame the MOT and say they should have spotted a warn bulb?
The MOT is just a very basic check to make sure the car is not a heap with no brakes, holes in the floor, no suspension and bald tytes.
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well crazy horse, the spring broke so replace it! the poor old MOT tester would of been dammed if he'd failed it for being rusty & Dammed for not spotting it. These springs break at any time on any make of car, merc's & Bmw's included. Astra's built a reputation for rear springs breaking but no more than any other car really.
They break at any time sometimes whilst parked overnite. just be grateful yours didn't break whilst doing 70 on a motorway & the coil dig into the tyre & rip it to shreads & drag you straight into a barrier.
I Doc
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Springs are made on the cheap now. A proper spring is bevelled and thinned for about half a turn at each end, so that it sits evenly, usually in a preformed rubber cushion.
That way there is no local distortion under compression, and the next turn rest or move away progressively with suspension movement. Modern springs are just cut off abruptly.
Look at the careful shaping on a valve spring as an illustration of how it should be done.
I've never had a properly made spring on an old car break - they just slowly sag with age. I've changed them after 20 years, but some have lasted over 40.
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