auto engine cut off when stopped

[NoCO2]

I was thinking about this early and I just want some questions answered and possibly some suggestions on how to do it if it's possible in a normal car.

I'm talking about how gasoline powered golf carts automatically kill their engines when they come to a stop and then you sort of pump the gas pedal once or twice to get it going again...why don't auto manufacturers do this? It seems like if golf carts could do it that it would be pretty simple for a normal car to do it, right?

If anyone has any knowledge into how this is done I would love to learn so I can see if it would be feasible on my car because if I could do it I think it would save a LOT of gas.

[SVOboy]

I'm pretty sure the VW lupo/polo had this feature, so it can prolly be worked out, but how easily I know not.

[apgrok1]

The engine has a generator/starter on it. It starts the engine, and after the engine starts, it charges the battery. Very old cars had this on them. Somehow, we went to a separate starter and a separate generator/alternator. If you were to try this, your generator/starter might need as much as 3 KW to start the engine.

[NoCO2]

hmmm...ok, so If I'm getting you right. All that you have to do is hook up an electric motor in place of the starter and make a way for it to be triggered by your gas pedal. Then once the engine gets going it lets the motor spin with the engine as an alternator and then your foot controls the intake valve like usual....hm...seems like this could be done...not with an automatic but a manual transmission car could probably do it...

[dcb]

Naw, you can probably teach your car to stop the engine if it has been idling for more than a certain amount of time (I think the diesel lupo turned it off after 8 seconds)

And likewise you can teach it to engage the starter if the
1. engine is off
2. the clutch pedal is pressed
3. the throttle is off ifle

Just switches/sensors/electronic bits to control the sequence of events.

[TomO]

For Honda owners, there is the ElectroCharger.


I just wonder about the wear and tear on the crank bearings from having power applied to the other end of the crank?

[s2man]

New BMWs will stop the engine when the care comes to a stop, and restart it when the clutch is depressed. Heavy duty starter included.

[Daox]

Yeah, as s2man said, more car manufacturers are going to this system to increase fuel economy. All the hybrids do it, and conventional engines will do it soon enough. There are problems though. For instance, there is no coolant being pumped through your heater core, so after a while it starts blowing cold air in the winter (a annoying problem for me while P&Ging). The Prius remedies this with an electric coolant pump that kicks in to circulate while the engine is off. There are also problems if the car is using conventional power steering instead of the newer cars that use electric assist power steering... Theres more, I just can't think of them atm.

[Whoops]

Originally Posted by TomO

For Honda owners, there is the ElectroCharger.


I just wonder about the wear and tear on the crank bearings from having power applied to the other end of the crank?

I've heard of this concept, before, except it was promoted more as a Electric Turbo Charger. The problem is that I didn't see any availability or pricing. The payment sheet allows you to be put on a waiting list, for an undisclosed period of time, for an unknown amount of money.

One primary issue with this would probably be whether you are trying to utilize something for just short term acceleration, in which case you could hit the motor hard and fast, but not for long enough to heat it up. On the other hand, you could add some suplemental torque, to assist the motor on a lower end basis.

I don't think I would want to be trying to use this to restart the motor, but it would largely depend on the size and width of the pullies and belts. As far as the crankshaft bearings are concerned, all of the engines I've worked on have the same size crankshaft bearings in the front of the bearing, as in the back, so I don't think that aspect would pose any undue or irregular problems.