Reason is handbrake had released - one theory / explanation put forward was the teeth on the lever connected part of the handbrake were not fully meshing with the teeth on the cable ratchet part of the handbrake. Vauxhall invited engineer appointed by BBC to speak to their engineers.
If this is the cause maybe making the teeth less rounded on the tops may help?
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I very rarely leave my car in gear when parked. If it is on a slope, I turn the front wheels slightly towards the kerb and ensure that the steering lock is engaged.
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What\'s for you won\'t pass you by
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The first thing I ever learnt about driving (must have been about 3 and watching my dad) was to check car was in neutral and handbrake was on before starting the engine. My dad would always leave the car in gear if parked up- or downhill (having learnt to drive in the 50s, when most cars had carp brakes.) From my instructor and reading the Highway Code (yes, really!) and, of course, Honest John, I have picked up other good habits which have now become second nature after nearly 25 years of driving.
The bad habit that makes me cringe most is the yanking on the handbrake without holding the button in.
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On levelish ground I never use the handbrake when leaving the car (yes I know it's illegal), instead relying on leaving the car in gear (2nd). I think this is a throwback to when I drove 70's Fords on which the drums would go oval if the handbrake was firmly applied.
I do wonder, though, what 'steepness' of slope the gears would hold on?
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>>I do wonder, though, what 'steepness' of slope the gears would hold on?
You need to know the friction torque required to turn the engine (a few tests with a torque wrench will give a good estimate), the gear ratios and the radius of the wheels. By applying the friction torque at the engine, and multiplying by the gear ratio and final drive ratio, and then dividing by the wheel radius, you get an equivalent tractive effort. If you equate the tractive effort with the component of the vehicle's weight which is aligned with the road [m*g*sin(theta)], you can solve for theta, the 'steepness'.
For the maximum steepness, use the largest ratio, i.e., reverse - or if you're worried about the engine turning backwards, first.
Number_Cruncher
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>>makes me cringe most is the yanking on the handbrake without holding the button in. <<
Yep! me too! - makes me want to go over and give them a slap! The only place for a "screaming ratchet" is on my fishing reel!.
Billy
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"The only place for a "screaming ratchet" is on my fishing reel!."
You've never driven an old MG with flyoff handbrake?
Some people have never lived.
I love the sound of cogs on a rack.. something primeval .. and then the screams and the tearing of sinews....
madf
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Always leave mine in gear, either 1st, 2nd or reverse depending what mood I'm in, or what hill I've parked on. Having said that, the engine struggles to move the car with the handbrake applied properly.
Possibly the problems with Vauxhalls are as a result of drivers not applying the handbrake fully? I used to drive a company van, and whenever one of the women drove it after me, they had to get me out to the carpark to put the handbrake down.
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>>makes me cringe most is the yanking on the handbrake without holding the button in.
Me too - but it does occur to me that this might be the problem in Vauxhall's case. If someone releases the handbrake button so the pawl rests on top a tooth, then it's possible to visualise how the handbrake could fly off. The woman in the car with the caravan attached that rolled away mentioned something about the handbrake banging down.
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My mum had this problem with her Hyundai Coupe so its no just Vauxhalls.
She filled her car up with petrol, went to pay and came out to find her car gone.
After the initial panic, she saw it had rolled down an embankment into a car park, luckily hitting nothing on its way. The handbrake was still fully applied.
The handbrake simply does not hold the car regardless of how hard it is applied.
Hyundais response was to send a sticker for the handbook suggesting that the car be left in gear.
We now do BUT theres one simple issue here that is being ignored - regardless of whether or not leaving it in gear is a good idea, the hand/parking brake should do just that: BRAKE the car, which clearly is not the case with some cars and is totally unacceptable.
My dads 14 year old Astra can hold its own weight on the handbrake without being left in gear as can my van and every other car ive ever owned, so why are certain newer cars being supplied with what is to all intents and purposes, a useless handbrake?
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I wonder with a faulty handbrake, how do people start the car on uphill.
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I've always left the car in gear as well as applying the handbrake - it's just habit. My dad's always done it so I think it just rubbed off. It's one of those things like taking off the seatbelt that I do subconsciously at the end of a journey.
The Mondeo's handbrake will hold it on every hill I've ever parked on, and the Renault's auto parking brake is superbly powerful, if a little hard to learn to trust.
The Renault has the "Press Clutch or brake" thing before the starter button will work, and it's also intelligent enough to tell you to "select neutral or press clutch" if you try to start it in gear to avoid any kangaroo embarrassment. Like SWMBO every time she gets in the Mondeo (she never checks) Rrrrr..clunk... "(insert choice of swear word)".. heh heh.. :-)
Cheers
DP
--
04 Grand Scenic 1.9 dCi Dynamique
00 Mondeo 1.8TD LX
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Even if the pawl rests on top of one tooth on the ratchet,it should drop into the next one-it's springloaded after all-no mention of how poor the average DISC handbrake is compared with DRUM-so much so that some manufacturers fit a drum on the disc just for the handbrake.
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The handbrake simply does not hold the car regardless of how hard it is applied.
I find it hard to believe that that can be considered acceptable - surely it wouldn't pass the MOT? I assume the retardation test on the MOT would directly relate to the handbrake's ability to hold the car.
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My BMW 330d would not hold on a hill from new ... And it had to go to two dealers before it was properly adjusted ... and it then was fine for the next 4 years.
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When one was brought up with cars where handbrakes were only something to worry about when the ministry of transport test came around back then we all left cars in gear
I had the dubious pleasure of being run down by a HC Viva after my brother started it in gear
Edited by Pugugly {P} on 05/10/2007 at 18:51
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>>I assume the retardation test on the MOT would directly relate to the handbrake's ability to hold the car.
Yes, that's true.
efficiencies=[0.16 0.25]; grades=1./(tan(asin(efficiencies))); str1=['For ',num2str(efficiencies(1)),' handbrake efficiency, the car holds on a 1 in ',num2str(grades(1)),' hill']; str2=['For ',num2str(efficiencies(2)),' handbrake efficiency, the car holds on a 1 in ',num2str(grades(2)),' hill']; strvcat(str1,str2)
ans =
For 0.16 handbrake efficiency, the car holds on a 1 in 6.1695 hill
For 0.25 handbrake efficiency, the car holds on a 1 in 3.873 hill
Number_Cruncher
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I find it hard to believe that that can be considered acceptable - surely it wouldn't pass the MOT? I assume the retardation test on the MOT would directly relate to the handbrake's ability to hold the car. <<
I did wonder about this, the first MOT is in July, it will be very interesting.
What can be done about it im not sure as Hyundai tried adjusting it but got nowhere and Hyundais response was the sticker, eerily like Vauxhall's response.
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Working behind the scenes on this little issue, its suprising how many people argue the toss about parking in gear.
You wouldn't believe how many Driving Instructors have called and said they don't teach people this. Although they should be teaching you how to work and look after a vehicle as per the Highway Code!
The only theory that holds water is the teeth not meshing. Dont press the button and this shouldnt be a problem.
The stickers were on VOSA's 'recommendation' and I think some manufacturers have such things as standard on the sun visor.
Truth is more than likely that there is no inherent fault and it is just down to a bit of a naff, albeit it still workable, design. E.g. The handbrake is set quite far back (especially for those that need to be closer to the steering wheel) and needs a good yank with the brake pedal pressed.
I never used to park in gear, but after working here, its something I ALWAYS do, even in the staff carpark :-)
Edited by figure_in_kuro on 19/10/2007 at 13:10
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Can be quite a lot a stake.
My ex. related a tale where her date took to her the local 'beauty spot' which was dark and secluded.
Passions were high and attentions were focussed on matters other than handbrake efficiency when the earth moved prematurely, matey climbed into the front and switched the lights on to find out that the car had rolled down the lane, across the verge and into a small ditch.
He had to call a mate to tow him out , ex was severely ticked as she got home after 2 and he never discovered her most intimate charms.
Made me smile.
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