That only works when you’re diligent about keeping them in your vehicle and nobody in your family takes them.
You could if you crack the window an inch or two open and let the car fill before fully opening the window.
I believe those Coffman “shotgun” starters for those large radial engines actually used 4 gauge blanks.
I’ve push started my 4 banger Corolla successfully several times, even tho the battery didn’t have enough juice to crank the engine. The compression is pretty high on the 4afe engine, 10.2. I believe I could start it by hand cranking. Not as sure about hand-crank starting my v8 truck tho. It’s compression is lower, 8.2, but there are twice as many cylinders to overcome. But even if hand-cranking the Ford 302 wasn’t possible, I’d still find it useful to be able to easily rotate the engine by hand when setting the gap in the ignition points, and for other jobs that required setting the crankshaft at a certain position.
Mythbusters did a really informative episode on this topic. It’s something well worth watching, if you have a chance. Poster kolby is correct, they found it absolutely impossible to open the windows or the doors once the car was more than a few feet under water. You can’t even crack the windows open an inch. Due to the pressure of the water against the surface of the car. Once you find yourself in this position, and you don’t have access to a tool which could break the window, you only have one choice: Wait until the inside of the car almost completely fills w/water. You have to wait a long time, until there’s just a small air bubble up near the roof. And you might have to do some significant gymnastics to keep your head in the air bubble while waiting if the car is rolling around due to the water currents. If you manage to do all that, you have probably sunk all the way to the bottom. And very dark. At this point you can open the door or window and get out, but you are looking at a really long swim to reach the surface while attempting to hold your breath. Assuming you can figure out which way is up. All in all, not a good situation.
The above scenario can be avoided if you have the presence of mind to open a window, or preferably all the windows, immediately, as soon as you notice you are heading into the river. It’s sort of counterintuitive thing to do, but from what Mythbuster’s showed, it is probably the best way to improve your odds of survival.
Around here ice fisherman are told to drive on the lake with their window open just for that reason. Also if the car starts to go down, opening the door right away can help keep the car up enough for you to jump out. It’s not a bad idea to have one of those window breakers in the door pocket though.
You folks reminded me of my escapades with my Morris Minor. Always had a problem starting it but would often just push it and jump in and pop the clutch. Sometimes it took a block or two to get it going. One time we were at the drive in with it and ended up pushing it up the hill and then pop the clutch going down again, rinse and repeat. Why do I want another one?
Yes, why not?
A battery too dead to crank the engine can still power the fuel pump and injectors.
A 1.5 liter four could easily be hand cranked, even with high compression ratios. I successfully roll started my MT Yaris when the battery was too dead to crank the engine, it lit right off. I had to do the same with a Kawasaki ZRX1200 motorcycle once because the battery was too dead to crank it. It also lit right off when I released the clutch, and it was a “high compression engine”.
Small fours are not that hard to crank.
Now, a 321 cubic inch two cylinder engine in a John Deere A model tractor is a different story. Without the compression releases open, it takes someone bigger than me to crank that flywheel over the compression stroke.
That’s why not, right there in the quote. If the battery cannot support fuel and spark, the engine won’t fire. There can be enough energy in the pattery to run the fuel system but not turn the engine over but a stone dead battery won’t even bump start the car if there is no fuel or spark.
Now roll starting a car uses the mass to turn the engine over. It takes a bit to get that mass rolling to pop the clutch to start it. You get out, push the car to get it rolling and then hop in and pop the clutch. Much more time went into getting that mass rolling than turning a hand crank against compression. And if the fuel injectors aren’t firing, you aren’t starting.
Yes if your battery is that dead, pushing the car is just a waste of time, but usually, a battery too dead to crank the engine will still run the ignition and fuel pump.
Also, I had no problems turning the crank of that 1.2 liter four in my motorcycle with a ratchet wrench and socket while checking valve clearances, with the spark plugs installed. It’s just not that hard to crank a small four.
You could very likely hand crank a 1.2 liter four cylinder diesel engine.
You think so? With 17:1 (or more) compression ratio? I’d don’t have that much arm! 
I’m not gonna offer to arm wrestle you!
Guys, batteries don’t immediately fail when submerged in marine water let alone fresh water lakes. That’s the stuff of Hollywood but not reality. Water is actually a relatively poor conductor, especially at low voltages like your car battery. Ever seen a car submerged with the lights still shining? You could open the window, climb out, swim to shore and sit there for 1/2 hour waiting for the tow truck to show up and your battery would still be fine. In fact, it would takes days in a fresh water lake to discharge appreciably.
If you doubt it, I challenge you to use your DVM (which is likely to have a 9V battery for resistance measurements) and hold the probes 8" apart in water. Now place them even 1" apart. What did you read? Now use ohms law and see how much current would flow between your submerged battery terminals…
Secondly, with modern batteries, water intrusion wouldn’t be an issue either over the course of 24-48 hours. They are sealed well enough such that there is no incentive for water to enter the battery in such a short time. Seen a few submerged batteries on boats in both fresh water and marine environments and they had plenty of charge left in them the next day…
Cars don’t sink instantly. Unless you’re knocked unconscious, you have plenty of time to open windows or doors.
It’s not that the battery dies. It’s that the water pressure pins the window against the frame, and the motor’s not strong enough to move it, once the car’s a couple of feet under water. Do it early enough, it’ll open.
What about this method?
I’m still concerned that the large volume of water flowing in could potentially throw you back and either disorient you or (worst case) cause you to hit your head on a hard surface in the interior of the vehicle and knock you out.
I am now so worried about my car going under water and the power windows not opening that I am replacing the windows with side curtains.
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Be sure to get side curtains made of Isinglass.
Since that substance is made from the swim bladders of fish, it just might help to keep you afloat!
(The two of us might be the only ones on this board who are familiar with Isinglass)
It is difficult to break a door glass by striking it with a hammer when out of the water. Under water it would be much more difficult to swing a hammer fast enough to break the glass.
I remember isinglass well. On the subject of hand cranks, my dad never wanted a Ford. When I asked him why, he said that Fords were hard to start in cold weather and you had to crank them a long time to get them started. I didn’t think having to run the starter a little longer was any big deal until he told me about taking a girl to a college dance in his parents’ Model T Ford. While the dance was going on, the temperature dropped. When he was hand cranking the Model T to get it started (it didn’t have an electric starter) his date left with someone else. I said, “Look on the bright side, Dad. Suppose the Model T had fired right off. You and this date might have gotten serious, you would have married her and I wouldn’t be here”. He replied, “That’s why I don’t like Fords”.
I am sure the regulars on this board wish that Model T had fired right off, but you are stuck with me.
Not sure I understand what you mean RK. If the interior was already filled with water there’d be no need to break the glass right? The pressure would be equalized & you could just open the door. Or do you mean that if the car is underwater but the passenger compartment remains dry, the pressure of the water on the outside against the glass would make it even more difficult to break the glass, even if you had something to strike it with from the inside?
Per NOAA, when you are at sea level, you are subjected to 1 atmosphere of pressure on every square inch of your body (approx 14.6 lbs). For every 10 meters deep (approx 32.8 feet) the water is, the pressure increases by 1 atmosphere. So while the pressure increase isn’t great in the initial 10 feet, it’s enough pressure pushing against the outside of the car that it’s difficult to break the glass even if you have something to strike it with.
https://www.pmel.noaa.gov/eoi/nemo1998/education/pressure.html
Can you swing your arm as fast under water as you can out of the water?