Idling an engine
Discussion
Super Sonic said:
The vehicle doesn't have to be moving for the alternator to be engaged, it's driven by a belt from the crankshaft, so is working whenever the engine is running.
^^^This.^^^And that was one of the main reasons for the change to alternators in the sixties, because they were working at engine idling speeds.
There's often a clutch on the alternator pulley but it's not for disengaging the alternator, it's to allow the alternator to spin more quickly than it would be driven by the belt. Without that clutch the alternator, which is quite hefty, will be trying to push the engine when you lift off the the throttle, knackering the drive belt etc.
Yes, the whole point of an alternator is that it's generating a decent amount of electricity even at very low rpm and easily enough to charge the battery as well as running other systems - unlike an old-fashioned dynamo. At tick-over a dynamo car will be slowly draining its battery, hence the enthusiasm for revving as soon as they've been jump-started or bump-started.
Leaf-blower has neither alternator not dynamo. Its magneto is another permanent magnet device which combines the function of coil and distributor, delivering immediate HT direct to the spark plug.
Yes, the whole point of an alternator is that it's generating a decent amount of electricity even at very low rpm and easily enough to charge the battery as well as running other systems - unlike an old-fashioned dynamo. At tick-over a dynamo car will be slowly draining its battery, hence the enthusiasm for revving as soon as they've been jump-started or bump-started.
Leaf-blower has neither alternator not dynamo. Its magneto is another permanent magnet device which combines the function of coil and distributor, delivering immediate HT direct to the spark plug.
Super Sonic said:
The vehicle doesn't have to be moving for the alternator to be engaged, it's driven by a belt from the crankshaft, so is working whenever the engine is running.
So let me get this straight. If the battery wasn't totally knackered, I could put a charge back in it just by idling/ticking over the engine without actually having to drive the car???Sebring440 said:
^^^This.^^^
And that was one of the main reasons for the change to alternators in the sixties, because they were working at engine idling speeds.
So let me get this straight. If the battery wasn't totally knackered, I could put a charge back in it just by idling/ticking over the engine without actually having to drive the car???And that was one of the main reasons for the change to alternators in the sixties, because they were working at engine idling speeds.
1Steve68 said:
Super Sonic said:
The vehicle doesn't have to be moving for the alternator to be engaged, it's driven by a belt from the crankshaft, so is working whenever the engine is running.
So let me get this straight. If the battery wasn't totally knackered, I could put a charge back in it just by idling/ticking over the engine without actually having to drive the car???But a battery charger would be easier and less irritating for your neighbours
ARH said:
Yep, It will work.
But a battery charger would be easier and less irritating for your neighbours
I bought one a few days ago (charger) but under the bonnet of my car is really complicated and I can't even see the battery. It would take me a few hours of removing bolts, screws, and plastic panels, just to get to the battery and change or charge it !But a battery charger would be easier and less irritating for your neighbours
1Steve68 said:
ARH said:
Yep, It will work.
But a battery charger would be easier and less irritating for your neighbours
I bought one a few days ago (charger) but under the bonnet of my car is really complicated and I can't even see the battery. It would take me a few hours of removing bolts, screws, and plastic panels, just to get to the battery and change or charge it !But a battery charger would be easier and less irritating for your neighbours
1Steve68 said:
ARH said:
Yep, It will work.
But a battery charger would be easier and less irritating for your neighbours
I bought one a few days ago (charger) but under the bonnet of my car is really complicated and I can't even see the battery. It would take me a few hours of removing bolts, screws, and plastic panels, just to get to the battery and change or charge it !But a battery charger would be easier and less irritating for your neighbours
Have you checked if there is a charging point somewhere else? Sometimes cars with hard to access batteries have one.
Failing that is the cigarette lighter (or accessory socket) live when the car is off? If so you can trickle charge from that.
Panamax said:
There's often a clutch on the alternator pulley but it's not for disengaging the alternator, it's to allow the alternator to spin more quickly than it would be driven by the belt. Without that clutch the alternator, which is quite hefty, will be trying to push the engine when you lift off the the throttle, knackering the drive belt etc.
An alternator could in no way turn an engine over by running faster, they don't carry that much of a flywheel effect. Having said that yes, you are right in that the clutch is there to prevent stretch/wear on the drive belt.98elise said:
You don't need direct access to the battery to charge it.
Have you checked if there is a charging point somewhere else? Sometimes cars with hard to access batteries have one.
Failing that is the cigarette lighter (or accessory socket) live when the car is off? If so you can trickle charge from that.
Interesting, but I think I'll leave this to the professionals. Seems like too much hassle for me.....Have you checked if there is a charging point somewhere else? Sometimes cars with hard to access batteries have one.
Failing that is the cigarette lighter (or accessory socket) live when the car is off? If so you can trickle charge from that.
Indeed the battery is very accessible. See photo 2022 C3. OP it's the thing on the RHS of the photo. The +ve terminal has the red cover over the terminals. The one at the other end is the -ve.
If you apply a charger or conditioner you will need to clip the +ve lead onto the battery, obviously you will have to remove the red plastic shield to get access and the -ve onto a metal piece of the body. This is how I connect the ctek onto my daughter's C3 and it's easy.
Come on things are not that difficult. Get it started per your other thread and run it for a while, see what happens.
If you apply a charger or conditioner you will need to clip the +ve lead onto the battery, obviously you will have to remove the red plastic shield to get access and the -ve onto a metal piece of the body. This is how I connect the ctek onto my daughter's C3 and it's easy.
Come on things are not that difficult. Get it started per your other thread and run it for a while, see what happens.
If the battery is completely flat and you jump start the engine its best to switch something on to give the electrical system something to power, hazard lights (bulbs because leds might not take enough power) are ideal because you're less likely to not notice the vehicle is still running.
I've known cars be jump started and left running for hours on end (sometimes several days unnoticed until the fuel finally ran out) in compounds, only for the battery to still be flat if nothing was switched on.
I've known cars be jump started and left running for hours on end (sometimes several days unnoticed until the fuel finally ran out) in compounds, only for the battery to still be flat if nothing was switched on.
Smint said:
If the battery is completely flat and you jump start the engine its best to switch something on to give the electrical system something to power, hazard lights (bulbs because leds might not take enough power) are ideal because you're less likely to not notice the vehicle is still running.
I've known cars be jump started and left running for hours on end (sometimes several days unnoticed until the fuel finally ran out) in compounds, only for the battery to still be flat if nothing was switched on.
If the battery was still flat, its a battery issue. Once engine is running it will charge the battery, no need for other loads... the flat battery would be enough load. I've known cars be jump started and left running for hours on end (sometimes several days unnoticed until the fuel finally ran out) in compounds, only for the battery to still be flat if nothing was switched on.
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