Need ways to start a car with a dead battery.- 92 Civic Auto.

It was sufficiently 'dead' so that the car would not start. I wouldn't bump start a car for fun!

Reply to
Mark Hewitt
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If car batteries were recharged at a 10Amp rate frequently, they wouldn't last very long. The recharge is more likely limited to 5 or 6Amps, maximum.

2 or 3Amps would be ideal. I know that 10Amp battery chargers are common, but it wouldn't be a good idea to use them on the same battery on a daily basis. -Dave
Reply to
Mike T.

Well, no kidding. These gadgets are for the rare occasion that someone FORGETS to turn off lights, or perhaps one door doesn't close completely, causing the dome light to stay on all night.

You've NEVER had a discharged battery?

Reply to
Larry Bud

Not from any of the causes that have been cited in this thread. And I don't believe in "latest/biggest/bestest/most-tech-est" just because it's there - Which is one of the primary reasons why I drive an older, carbed, non-computer-controlled, not-automatic vehicle that can easily be started with a quick push and clutch-pop.

Reply to
Don Bruder

Once upon a time (80's to early 90's?) there were car batteries sold with smaller backup batteries built-in. This back-up was always charged off the the main supply, but they had to be manually switched on if the primary battery was drained. The brand I recall was Champion (as in the spark plugs). I think it was just a trademark licensee using the brand name.

Reply to
y_p_w

Your alternator is NOT a trickle charger. There's nothing in there to limit the recharge rate aside from the alternator's capacity.

Reply to
Matthew Russotto

There is no current-limiting on any car's charging system, other than the fact that when you jam 30+ amps into a battery, it builds up a back-voltage very quickly. The voltage regulator puts between 13.8 and

14.5 volts across the battery's terminals, and however much current the battery will take is what flows into it.

A battery that's just been discharged by an engine start is not very deeply discharged, and the few seconds of large inrush current doesn't hurt it. But this is exactly why a DEEPLY discharged battery should (ideally) be recharged by a plug-in current-regulated charger and NOT the car's non-current-limited charging system.

Reply to
Steve

You do understand that when you push-start a car, that causes the alternator to spin, which generates electricity, right?

Some old fashioned components need electricity too like, oh, spark plugs?

Why do you think that a jumpstarted car's engine continues to run, even after the other car's battery is disconnected?

Reply to
Kaz Kylheku

Actually, once the alternator is going, it will power the fuel injection and the sparkplugs. How much fuel injection can happen before there is enough current for the ignition coil, right? Can the fuel pump get into action faster than the ignition system? What's faster, spinning up a fuel pump, or building up field in a coil?

I read about this cat burning risk, but now the more I thinkg about it, the more it sounds like complete bullshit. As in, aside from the the converter being able to take it, it never actually happens.

Thanks for providing some perspective on this.

Reply to
Kaz Kylheku

Yes. About 2-6 amps overnight. But, a charge from the alternator on a dead battery is better than a poke in the eye with a sharp stick.

nb

Reply to
notbob

Sorry, but if you had read the thread you would have found out that most alternators need power input to turn on when they spins up. No battery, no alternator power.

Pushing the vehicle will not turn on the alternator with a flat battery. Boosting it gives the alternator power to turn 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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Reply to
Mike Romain

Kaz Kylheku wrote: .

The problem is, the engine computer needs a certain MINIMUM voltage to operate. It is difficult to push the car fast enough to get the generator/alternator to a high enough speed that it can maintain that voltage AND charge the dead battery. I have always had stick shift cars, and those used to be easy to push start- until the engine management computers. Then,with those computers, if the battery was really dead, no go.

Reply to
Don Stauffer

FWIW, i personally push started a 98 corolla. the battery didnt have enough juice to turn the starter, but apparently it had enough to get the ECU to work for the time being.

Reply to
SoCalMike

Did you try /disconnecting/ the dead battery? There is no point of a dead battery being in the circuit during starting. All it does is suck up current. You can reconnect it when the engine is running. Or maybe not. If the battery is really completely dead, it's probably better to charge it with a proper current-limiting charger anyway. If you can get to a charger without too many more push-starts (ideally zero), I'd do it that way.

Reply to
Kaz Kylheku

Yes, they need a field current. But that has nothing to do with the car being modern, does it? Are alternators considered modern?

With a completely, utterly flat battery, no.

Reply to
Kaz Kylheku

My first car had a generator, so for me only modern cars have alternators. For that matter they also have power steering, servo brakes, electronic ignition not to mention radial tires........

Reply to
Bozo

Considering the alternator will barely charge the battery when the car is idling (say about 800rpm), you're gonna be pulling that rope for a looooooong time to do any good.

I think you're going to have to a. Install an alarm device to remind you to turn lights etc. off. or b. Learn from your previous mistakes... ;)

Cheers, Steve

Reply to
sgam

My first car pushed its pistons using carbon dioxide released by baking soda dumped into water. Crazy, drag-racing daredevils used metallic sodium instead, which releases hydrogen! Some of these guys would actually light the exhaust on purpose to create dramatic flames. (Using their Cuban cigars, of course). Then some clever, inventive type tried lighting the hydrogen /within/ the cylinder for additional power, having come up with a mechanism for mixing the gas with air before it enters the cylinder chamber. The internal combustion engine was born!

By the way it took nearly a decade to replace the in-cylinder Cuban cigars by the invention known as the spark plug. Early ignition coils were powered by banks of potatoes with zinc and copper electrodes stuck into them.

(The web page

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gives a good gist of this). There were folks who grumbled about how their old-fashioned steam cars could be made to start and run on whatever available material that could be found that would burn, plus whatever water one could find.

Reply to
Kaz Kylheku

my 98 civic hatch doesnt, and i kinda like it that way.

Reply to
SoCalMike

You seem to be a little behind. If your battery is actually dead, the alternator doesn't generate electricity when it spins.

And if the spark plugs fire, you don't need to worry about unburned fuel-air mixture in your exhaust because the mixture will ignite.

Reply to
Matthew Russotto

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