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Can you push start a car with dead battery & dead alternator?

Manual transmission of course. Can I start it rolling down a slant hill ? Car is running off of battery (alt dead) …I’m not sure it will last til by service app. next Monday. Thanx for any practical advice. - Tom

No. You have to replace/repair the alternator.

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It takes far less amperage to run a fuel pump and ignition system than to run a starter motor - it very well might start with a push or a roll. But if the alternator is not working, every minute it runs it is discharging the battery. If you can put it on a charger fairly soon, it could be good to go again.

This could be fun, or not. Depends on the circumstances. Good luck!

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no, you just have to get power in the battery depending on the year of the car and how much stuff runs on battery will depend on how far you can go but if the battery is dead then NOTHING will work at all you need power in order for the coils to fire off the cylinders and to ignite the stator in the alternator to start charging however you can still run a car without an alternator but you must have battery power no matter what

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by the way some of the old clasic cars 60s 70s with auto trans could be pushed started as well at about 30 mph put them in gear and they would start

True. And theoretically, if you have to limp home on battery power, you’d be better off disconnecting the inoperative alternator from the electrical system. No sense using juice to excite the alternator field when the alternator isn’t producing power.

Light airplanes have “split” type master switches which enable the pilot to switch off the alternator just for that reason (alternator failure).

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if the car has a carburetor you most likely don’t even have an electric fuel pump so no drain there if its an older set up with points and condenser again even less energy will be used and the car can run on 6 volts or less but most cars with computers will die at about 9 volts

the car is 1992 plymouth laser , fuel injection …I know it does have a rotor

That was true in the 50’s or early 60’s, but by 1970 no automatic transmission that I know of had a rear pump, which is necessary to push start an automatic.

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The OP has a manual transmission.
To answer his question, in my opinion, though it might have enough power left in the battery for it to start it is very risky to drive it, may loose power at anytime.

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True. Best to drive downhill to a battery charger.

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Not much of a chance it will run more than 1 hour if that.

Had an alternator died on me in the rain. I had to have the lights and wipers on. The battery lasted about 15 minutes

Btw, it was an mt car. No electrical drain for the transmission control unit

GM used the Power Glide tranny untill 1973 this tranny would push start

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I forgot about that one. I’m not much of a GM guy.

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yeah we know and we all ready answered his question this is just some after thoughts and histroy facts.

Reminds me of an incident when my son was in his teens. I’ll share it for the humor.
We were riding atvs and motorcycles on some trails. He went to start his and it turned over really slow. I said try to push start it. He wasn’t sure what I meant so I tried to explain. His friend started pushing while he was pressing the start button. He didn’t understand how mechanical things work.
He’s a pharmacist now. Much smarter than I am.

No surprise there, given your screen name :smiley:

Not necessarily, just educated

You don’t learn everything you need to get thru life from books, experiance is still the best teacher!

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