Roll-starting a vehicle

No! Just don't use first gear. Use 2nd gear, release the clutch smoothly and be ready to disengage the clutch when it starts. I haven't had to do this for many years but have never experienced any ill effects from starting my car or truck this way.

also another point. On a few of the vehicles I've roll started if the battery was completely dead it took quite a decent hill to spin the engine enough so that the fuel pump would power up and the car would actually run. I'd always just try and give it gas then as soon as it accelerated I'd pop it into neutral and let the battery charge for a bit.

Also it is possible to roll start an automatic but I'd only try that on a rental.

Cheers,

-Dru

Is is real easy on a carburated engine (that is how you start a lawnmower)

Is is possible, but not recommended, on a engine with indirect fuel injection. There is no power to the computer and the sensors, it may not fire at all if there is no residual pressure in the fuel lines. You may meed a hill to let gravity supply enough rpm to the the generator going.

It is next to impossible on a direct injected engine. The injector pump has to generate enough pressure for the injection to occur

I stand to be corrected but it's been quite a few years since you could roll start an automatic. When they did away with the rear pump the trans would no longer turn the engine over. Dave

The speed that the auto will lock up is around 50MPH but unlikely to get that fast when just rolling down a hill, you would need to be towed then if theres another vehicle there you could just jump start it. (Thats a whole new thread on how to properly jump a vehicle but if anyones interested....)

If the battery has no charge what-so-ever you probably wont roll start it as the alternator requires a voltage to get charging started to supply power to the coil(s).

| > Also it is possible to roll start an automatic but I'd only try that on a | > rental. | >

| > Cheers, | > -Dru | | I stand to be corrected but it's been quite a few years | since you could roll start an automatic. When they did away | with the rear pump the trans would no longer turn the engine | over. | Dave |

Reminds me of an old, old joke.

This guy was stranded along the highway and a woman stopped to see if she could help.

He said, "His battery was dead and he couldn't push start his car."

She said, "Why not?"

He said, "Because it has an automatic transmission and the car has to be going at least 35 mph to turn the engine over."

She says, "That's not a problem.", and turns around to get her car behind him.

He looks up in his rear view mirror and sees her coming up behind him at

40mph.

Admittedly I haven't seen more than 1 roll started but it was a 99 or so Ford Crew Cab Truck. It would periodically not start for no good reason and so one day out on the block we were all pissed off and decided to try and roll start it. We were up in the mountains so we had a pretty good hill to go for it. We got it up to around 60 and then popped er into drive and she started.

That joke is still funny. Thanks, I got a chuckle out of that.

It depends.

If you do it all of the time, it can be hard on the drive train, but if it is a way to work around a dead battery, then the harm is mimimal, and is offset by the obvious benefit of getting the motor to run.

Select the highest possible gear that will get the motor turning, generally

2nd works when the car is pushed by people, and 3rd is good if you get a push by another vehicle.

I would descourage any attempt to push-start a car that is equipped with an automatic trans. The transmission will not usually turn the motor over.