On the way into work this morning, arrive at junction in town centre to see a wheel & tyre lying in the middle of the next lane.
As a rather unhappy looking lady goes to retrieve the wheel, I notice she is walking away from a three-wheeled hyundoo getiz or similar small thing, sat at a very uncomfortable angle. When she picked the wheel up, I could see that the brake drum was still attached to the wheel, and I could see the clean, bright, inside end of four wheelnuts poking through (or the bright spots where four wheel nuts/studs had all suddenly sheared simoultaneously.
What could have caused such a catastrophic failure ?
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Sure it wasn't a Suzuki Liana - another reasonably-priced car?
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How I feel for the woman, similar happened to me and it was pretty scarry - although in my case it was just the wheel which came off. the large tyre fitting centre who had just replaced the tyres didnt screw the nuts on properly!!!!!
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She's lucky it was a rear wheel, so I presume it didn't ground? Maybe this is a severe case of where wheel nuts have been overtightened, with greased thread, and the bolts have sheared under tension.
I have a (tyre related) question. Why is it that if your wheel falls off you see it travelling up the road ahead of you? Is this just urban myth?
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If the drum was still attached to the wheel, then the hub nut has come undone or the stub axle has sheared off - under or overtightening of the hub nut seems the probable cause.
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RichardW
Is it illogical? It must be Citroen....
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If the drum was still attached to the wheel, then the hub nut has come undone or the stub axle has sheared off - under or overtightening of the hub nut seems the probable cause. --
Some cars have the drum held in place by a small counter sunk screw though fully secured by the wheel nuts when the wheel is bolted in place (i.e. Metro) on others the drum is held on by the hub nut and contains part of the wheel bearing (i.e. Clio).
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I have a (tyre related) question. Why is it that if your wheel falls off you see it travelling up the road ahead of you? Is this just urban myth?
Something to do with, at the moment of disengagement, same amount of force being fed to the wheel, but suddenly less mass, therefore more acceleration?
Plus, hopefully the driver of the car tries to slow down pretty sharpish! ;)
My mother occasionally tells a story of losing a wheel, and in that one it overtakes her, so I can confirm that it does happen.
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Something to do with, at the moment of disengagement, same amount of force being fed to the wheel, but suddenly less mass, therefore more acceleration? Plus, hopefully the driver of the car tries to slow down pretty sharpish! ;) My mother occasionally tells a story of losing a wheel, and in that one it overtakes her, so I can confirm that it does happen.
I think you may be onto something there BazzaBear.
I had a little think about this myself, and I think another explanation might be do to with the sudden off-loading of the tyre, i.e the wheel is travelling with the same angular velocity as it did when it was on the vehicle, but the tyre suddenly has a greater radius at the road contact point, because the tyre isn't being squashed by the weight of the car any more.
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<< Why is it that if your wheel falls off you see it travelling up theroad ahead of you? Is this just urban myth?
At the instant that the wheel comes off, the wheel and the car are travelling at the same speed. After the wheel comes off, the wheel just keeps on rolling along (a bit like dat ol' man river!) whereas something on the car starts dragging on the ground which slows the car down more than the wheel slows down.
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L\'escargot by name, but not by nature.
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I could see that the brakedrum was still attached to the wheel, and I could see the clean, bright, inside end of four wheelnuts poking through (or the bright spots where four wheel nuts/studs had all suddenly sheared simoultaneously.
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The purpose of wheel nuts or bolts is to attach the road wheel to the bake disk or drum so when you slow the brake media, the wheel slows. I don't think the wheel nuts would have sheared, much more likely that the big hub nut holding the bearing in place had come adrift. You don't say which end of the car lost the wheel; I imagine it would be the rear if it had a drum brake.
I was following a Mk 3 Cortina once which lost rear wheel, brake drum and half shaft at speed on the M1 near Leeds. Not a pretty sight and a real change-of-underwear moment for me.
Hawkeye
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Stranger in a strange land
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The more I think of it, the more I think you're right, Hawkeye. It was a rear wheel and it looked like the drum had come off the hub - you could see all the grease where the bearing ought to have been
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Acceleration? Mass? this is a Huyandai Getz we are talking about here. Not over endowed with either.
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I once drove alongside somebody's alternator belt as it bowled along for about 50 yards on the motorway - remarked to my daughter with remarkable insight "look, someone's lost their alternator belt" . Couple of minutes later a red battery shaped light came up on my dashboard. Managed to get home before the headlights faded completely away.
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My Father in Law had this happen to him in the rush hour at one of the busiest junctions in Stockwell ,South London.I believe he had a Singer Chamois at the time so it must have been in the seventies.
As he explained it he drew to a halt at the front of the queue at traffic lights and he saw his rear wheel go rolling past so this seems to be true and not an urban myth.
As the lights changed frustrated motorists blocked by his car pyhsically lifted it off the road so that the traffic could proceed.
He then called me to ask if I could collect him and was only slightly amused by my rendition of the classic song ' three wheels on my wagon'...
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I'm surprised more people don't realise that they should pull over as soon as safely possible if their alternator belt breaks.
I was under the impression that it drives the water pump on a lot of cars and continued driving leads to overheating. Perhaps there should be a big "STOP CAR NOW" light rather than a battery light...
Personally, it's not a huge issue for me because the water pump is driven from the cambelt on my car, but surely lots of people must be wrecking their engines.
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I know someone who's alternator belt snapped on the M1 at night, causing a load clunk and the battery light to come on. Car still driving OK, she carrys on for another 50 miles until the lights suddenly dim and engine dies.
Thankfully alternator did not drive water pump!
Jesse, I agree with the "STOP CAR NOW" approach. Car manufacturers don't realise that many people don't read the manual which would state "if the battery warning light comes on when driving then stop the car immediately".
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Time to break into song, "You picked a fine time to leave me loose wheel". Sorry couldn't help it
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>>Sorry couldn't help it>>
With a moniker like that I'm not surprised...:-))
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What\'s for you won\'t pass you by
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In theory it should be self evident. battery lights are red for a reason.
Red = Danger. Stop.
Same with oil light. Perhaps the french got it right after all in my old BX. That had no temp guage and one warning light. That lit up to tell you that your engine was (already)stuffed.
Curiosly enough, on my father in laws old robin, the battery light was red and oil pressure was amber, and neither was labelled-just two pretty lights when you turned the ignition on.
WTM
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my 2002 Honda Jazz only had a temp warning light but no gauge.
I didn't notice till after I bought it and that left me wondering whether I would have bought it if I had noticed.
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My Xantia, and some of the BX's before it had a big, red STOP light which came on if something critical happened. It worked, on one of the BX's the cam oil seal failed, the level dropped, the STOP light came on, with a secondary light for oil pressure, and SHMBO stopped. That simple light saved the engine.
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