I have been thinking of a good way to prevent stranding myself from a dead battery. It happened twice. Once at a beach from leaving my lights on. The other was at a college campus which the stereo and the dome light ran down the battery. Unlike the beach, the college campus have lots of helpful students with beat up cars that have jumper cables. Now, I have a new idea. Once my battery runs dry, I remove my alternator belt and wrap a rope around the alternator pulley. I then pull the rope so it'll turn 10 revolutions per pull. I keep doing this for about 20 times.
What is the possibility that this will supply enough charge to start the car. If not, can somebody think of a clever idea to start an automatic?
I don't think that a) you will spin the engine fast enough to start it or b) that if the battery is dead you will be able to generate enough juice while doing as you suggest to power up the engine electronics, fuel pump, etc. You *certainly* won't with the alternator belt removed.
If this is of real concern to you, I would get one of those "booster packs" and keep it in the trunk; alternately, get one of those gizmos that straps to the battery that will cut the power to the vehicle when the battery is significantly (but not fully) discharged - the idea is that there should be enough juice left for one good crank after you reset the thing.
Pretty much zero. You (and any three other guys you want to grab at random and consider together) simply ain't got enough "ooomph" in your whole body to put enough charge on a car sized battery to "git 'er started" that way without spending days or weeks (maybe even months) in the attempt. It'd depend on alternator, I imagine, but I'd expect that having the stator coils energized during the time it took you rewind the rope after each pull would burn more juice than you produced with the pull. Of course, that assumes you could even pull it over at all against the load the battery presents.
First clever idea: Don't do bonehead things like leaving the lights on at the beach (Yeah, I know, we all have brain-farts now and then) or just plain idiotically STUPID things like letting frat-boys use your
*CAR* as a *BOOM-BOX*. (for this one, I put on my best "Red Foreman" voice and say "Serves you right, dumbass!" with absolutely no attempt at being humorous) Notice that I used two different words there? A car is transportation. A boom-box is a music producing device. Learn and understand the difference, apply that undersanding, and you'll never have such a problem again - at least not from that source - Guess it can't rule out a brain-fart at the beach, huh? :)
Failing that, get a AAA card. I have yet to even hear RUMORS about a car with a battery so dead that a AAA card can't get it started, or to home or the shop. Remember Visa's "ATM fix EVERYTHING!" ad campaign a few years back? Well, when it comes to stranded cars, it ain't ATM that fixes everything - It's *AAA* :)
Sam Nickaby, was motivated to say this in rec.autos.driving on Tue, 14 Feb 2006 10:50:49 GMT:
Slim and none. From your proposal, you would turn the alternator 200 times (20 pulls * 10 revolutions per pull). Most cars (once the engine got running) would take about a couple of hours to charge a battery (IIRC) if charged that way (maybe less for a partial charge to just start the vehicle the next time). I don't know about your car, but mine idles at about 800 to 1000 revolutions per *minute* so as such, I doubt your plan would work.
Couple of ideas: either a) a membership in AAA or similar auto club or b) get a booster pack (or even a spare battery if you want to go to the expense) from the parts store and keep that in the trunk for the next time you have a dead battery...
Alternators do not produce any current unless there is enough charge in the battery to create the electromagnetic field. So you can huff and puff all you like, you won't get any results.
And if the voltage is too low on the battery, a push start on a manual transmissioned vehicle wont work either. The ECM or DCM wont work nor will the ignition fire.
A few times well stranded will perhaps teach you how to avoid this situation.
Actually, when you start your car ONCE, you have to drive 8 miles before the battery returns to it's previous charge state. That assumes that your car starts on the FIRST try, and that your electrical system (including alternator and battery) is in good condition. For every time you TRY to start the car, add another 8 miles for the alternator to recharge the battery. Also, that 8 miles is not at idle speed. More like 2000(ish) RPM or even faster on many vehicles. So if the alternator could be hand cranked, you would need at least 16,000 revolutions to give the battery enough juice to attempt to start the car ONCE. If it fails to start on the first try, another 16,000 revolutions would be needed. Yikes. -Dave
I wonder if the kids that come out of university these days can even look after themselves. Way too much spoon-feeding in today's so-called 'education'.
That 'used' to work before computers and electric fuel pumps, but I found out the hard way that push starting a modern vehicle with a dead battery is only good for exercise.
The fuel pump and computer need power or the engine won't start. The gent would be just as well off 'pull starting' on the alternator pulley...
The booster packs you carry in the trunk appear to work well. Several Jeepers I know bring them on bush camping trips so they can run an electric cooler without worrying about starting later.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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Follow the advice given in this thread -- it is very sound.
You should also know that every time you allow a battery to run down to the point where it does not start the car, you lose battery capacity. In other words, the battery will 'hold' a charge to a lesser degree, and this capacity degreases with every dead start. Eventually your battery will get to the point where it can't even light a dome light.
You may actually need a new battery at this point. If your battery has an issue, eventually your alternator will give out (yes, it does damage). Get it checked and replace it if it isn't any good.
It still works (I know from personal experience), but there is a catch. You have to push it with a car at speeds high enough to get the alternator turning fast enough to get the fuel pump and computer to power up. Then it will start. The last time I tried it, it took about 1/4 mile pushing at about 15 MPH with the clutch engaged in 2nd gear before the warning lights came on and it would start by popping the clutch (obviously it has to be in gear and spinning to build up the charge - to make it start, put the clutch back in and let it out again while still being pushed. I don't think you could do it by hand anymore. A long enough down hill run would probably still work.
Zero. Zip. Nada. For one thing, an alternator needs power to its field coil in order to charge. If you're battery is DEAD, then no power to the field means no charge. If your battery is just mostly dead (what is this, 'The Princess Bride?' :-) ) then just a few spins of the alternator won't be anything close to enough to start it.
They sell portable jump-start kits that basically have a motorcycle-sized gell-cell battery. They kinda work for small cars.
But the real answer is "don't run your battery down." Running a battery dead, jumpstarting (or starting using any method) and letting the alternator charge it is REALLY hard on a battery and drastically shortens its life. If you do run a battery dead, the best thing to do is charge it with a charger (4-10 amps max) and then start the car. If you have to jump-start, go ahead and do it, but this isn't something you should figure on doing regularly. Get in the habit of turning off things that might drain the battery!!!
Stop being an idiot and using power from the battery when the engine isn't running.
Best solution is to get a battery saver unit and install it. It will shut down the power when it senses a current draw. As for removing the belt and spinning the alternator. It will NEVER work. The alternator requires voltage to it before it will generate any power. Spinning it won't make any difference.
The 'obvious abuse' is what the OP stated, leaving the lights and/or stereo on.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06
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