You can start a diesel just like you can start a gasoline motor. In any case, if you let go the clutch and the motor jerks the car to a stop then that means you are in too low a gear and need to use a higher gear.
BTW, if you are going to push a car with another car the technique is to push until the car has enough speed, then let it go ahead and only then release the clutch. never release the clucth while the car is still being pushed.
There are some modern automatics that can be pushed started but it is not recommended. Automatics rely on the pump to push fluid throughout the transmission. Beside providing hydraulic pressure for the torque converter and the transmission clutches, the fluid also acts as a lubricant. When attempting to push start an automatic, the clutch pack will spin with the drive line but is not getting any lubrication. That is also the reason cars with automatic transmissions should not be towed.
When push starting a manual, have the transmission in 3rd or 4th gear. Push starting a car in first gear can spin the engine over too fast and cause some serious damage.
According to this site and others, the problem occurs because, when you’re push-starting a car, the engine is turning over, and pumping fuel, but not firing. This is why unburnt fuel gets into the exhaust. Apparently, according to another site I visited (but can’t seem to find again!) doing one quick push-start probably won’t get you in trouble, but repeated attempts is a prescription for trouble. Other sites, however, tell you never to do it. You pays your money, you takes your choice.
Can’t lay my hands on the cite at the moment, but what happens is that the fuel in the cat converter results in overheating that will, over time, destroy it. In extreme cases, however, it can melt the core of the converter completely, blocking the exhaust - at that point, the car won’t run at all.
OK I can buy the unburnt fuel argument if the battery is dead as any power the alternator produces will be sucked up by the battery and not have enough power to fire the plugs. But if you are push starting due to a broken starter I can’t see this damage happening.
Yeah, that’s basically what one site said on the subject: if the problem is, indeed, just a bad starter, you can get away with push-starting the car, since it will, in fact, start firing pretty quickly. But if the car still doesn’t start, your problem probably isn’t just a bad starter, so trying it again and again might lead to heartache!
No offense guys, but I seriously disbelieve that you managed to push-start an automatic-equipped car.
The clutch packs in an auto are not only lubed by, but engaged via the hydraulic fluid. The “at rest” position for all automatic transmissions is disenaged- meaning that the pressurized fluid engages the clutches, not disengages them.
I cannot imagine being able to push the car fast enough that the driveshaft will turn the clutchpacks fast enough that the sheer viscousness of the tranny fluid will turn the rest of the tranny fast enough that it will in turn drive the torque converter, which is itself an indirect coupling that must have hydraulic pressure and fluid flow in order to even move.
There is no mechancial coupling at all between the input and output of the torque converter. It relies on turbine-like vanes on one half driving fluid against the vanes on the other half (internally) in order to transfer power. Most converters will simply “freewheel” at anything under about 700 rpm, and have varying degrees of “slippage” (less than direct coupling) on up to anywhere from 1,800 rpm to 4,000 rpm depending on application.
So the driveshaft will have to spin fast enough to turn the clutches by mere viscous drag, and those in turn will have to spin fast enough to get the converter to the point it begins to transfer power itself… and then these two indirect couplings will have to transfer enough power to turn the engine over.
And, since there’s no active lubrication of the tailshaft, this all has to happen before the driveshaft destroys the unlubed bronze sleeve bushing that supports the output shaft.
Sorry- I want to see reliable cites about push-starting an auto equipped car, and not anecdotes. I’m all but certain it can’t be done.
My experience meshes with that of people who say you can’t do it in anything remotely modern that has an automatic tranny.
Here’s how you start an automatic transmission-equipped car in the absence of a battery charger (a method approximately as safe as pushing one car with another):
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Remove battery from functioning car (e.g., the same hypothetical car you were gonna use to push-start the dead car with).
Remove battery from dead car and replace with battery from functioning car. (If car A has top terminals and car B has side terminals, see Appendix A, “Choice Pit-worthy Cuss Words”)
Start car, which is presumably no longer dead.
Without turning off engine, remove battery from car. (Yes, engine keeps running because alternator makes electricity. If battery is dead due to alternator being dead, see Appendix A again). Hold live end of positive battery cable CAREFULLY in such a way that it does not contact any part of automobile body. If you have something akin to a rubber boot to stick it in, so much the better.
Place dead battery in battery cradle. Rehook battery cables, making sure to hook them to the correct posts. Positive cable first. At the precise moment of making contact between negative cable and battery, turn head away from battery as eyeball insurance against rare but not quite dismissable possibility of bad things happening. Tighten clamps or cable bolts.
Return other battery to car from whence it came.
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If you cant git a fast enough speed to successfully turn the engine, try useing a higher gear it puts the wheels at a bigger advantage. And as far as screwing up your catalytic converter(s) go on I will give you 20$ each for them as long as the pellets are still in them,(heh heh heh a guy I once knew took a truck load of them to the right place and made 17,000$ something about platinum I think). Your altenator, puts out 12.5V DC sometimes more and the battery isnt gonna suck enough to hamper starting the car. Push starting an auto, I drove dirt cars for 4 years and I would git mad the car would die and then the little old man on the tractor would come out and push you very fast to git you off the tiny 1/4 mile track and I tried several times to break away from him by enguaging the car in drive hoping it would start. The tractors they used would probally do 40 and they would run them wide open. Besides if your into racing you know that the alternator it riged with a switch so you can cut it from kicking in while racing it robs power. I have wrecked and had the battery pulled out of its box I just killed the power from the battery to the electrical and ran with only an alternator and vice versa. after a night of racing many times the battery would be toasted completly and not have anything left but a good push when I ran a 4-speed always did the trick.
In a modern car you very well could fry the electronics by removing the battery and ru solely off the alternator.
The last car I ran off the altnator soley was a '80 dodge omni 024
AHunter3, in a car equipped with an alternator if you remove the battery with the alternator running, you’ll most likely fry the alternator regulator diodes. Don’t do it.
Flashback! Wow, when had one it was a Plymouth Horizon, but you still have my sympathies.
Rebel307, GIT?
git= get=got dont blame me my ex g/f was from texas
oh and I am sorry to mention that I had forgot that they stopped making cars in 1984. I was reading on howstuffworks.com that some of todays cars have large 5.0 (302-305) engines ,large?? Man if a 5 litre is the best I can do I shouldnt even leave home. 350 (5.8) is the absolute smallist engine I will put in any of my cars and yes I build them myself, (want pictures?) My truck has a 400 modified (6.6) which has been punched out .040 so it may be a few CI bigger but it push starts with no trouble at all. got a .625 cam with 11-1 compression (gitting close to the diesel ratio) but its not exactly the compression ratio that counts here its the cylinder pressure in that case its close very close to a diesel. Cause of the long duration cam with its high lift it gits a big gulp of feul/air mix through the 850 double pumper holly. and its low geared at that so the engine is at an advantage. I am sure you dont want me to explain the mechanics that gear ratios play when push starting. Basically the higher the gear the less of an advantage the engine has while under its own power ( this is why we have trannys). With the low 3.37-1 gears I run the engine is almost always at an advantage under its own power. So if I push start I use 3rd gear or even 4th but the engin turns it will lock the wheels in 2nd or 1st which isnt used for anything other then pulling 3,000 pounds or better. And to git a better picture the truck weighs about 5,000 pounds at any time ( weighed it) unless its loaded. So wheel adheasion would seem to have a better chance as well. But still in 2nd and 1st they just lock down.