The battery will charge faster if you rev the engine faster. Why? Because the faster the crankshaft turns, the faster it turns the belt that runs the alternator. And the faster the alternator turns, the more electricity it produces to run all the electrical stuff in the car — and recharge the battery.
This confirmed that, yes, revving the engine does make a slight difference in the amount of voltage supplied by the donor car. However, it was a gain of merely a few hundredths of a volt—not enough to revive a dead battery.
How long should I idle my car to charge the battery?
The best way to keep your battery charged is to start your engine up every now and then and leave the car running for around 20 minutes at a time. This is called idling and this gives the opportunity for the battery to recharge itself.
Yes, absolutely. Alternator output in amperage raises with RPM, this does vary with the exact alternator — but typically you won't see full output until over 2000RPM. You can over-stress an alternator by modulating the field for high current at idle, you have to excite the field for longer periods of time.
Alternator may not generate sufficient charging voltage until alternator speed is greater than about 2000 RPM. Typically, alternators have their full output rated at 6000 RPM but can continue to spin up to 12,000 RPM or more without any additional increase in output.
Too much revving will keep the valve present in the valve train for quite a long, wreaking havoc on them without fail. It might even result in valve float, getting stuck amidst an open and closed position, resulting in your car's power loss.
your engine is revving the same whether the engine is in park/neutral or any gear. the only difference is that there is no load on the engine so its not working quiet as hard as it is when its driving. all moving parts eventually wear...
Will idling a car for 30 minutes charge the battery?
While it is technically possible to charge your car battery by just idling, it's not very efficient. You'd likely have to leave your car running for hours to even come close to a full charge. This is due to the amount of charge that is initially lost when cranking the engine.
At highway speeds, your engine's running hard enough for the alternator to send spare amps to the battery. But when parked, the engine doesn't have spare amps. No, you can't charge a car battery while idling. At best, it'll charge the battery a few amps, but not nearly the hundreds of amps it took to start the engine.
Idling your car to charge the battery does more harm than good. Some people suggest idling your car for 15-20 minutes to recharge the battery, but this is not always recommended.
As the engine's RPMs climb, the engine is being put under a heavier load. This allows for any sort of knocking, squealing, etc to be much louder and easier to identify. Revving the engine can also insure that you have the correct amount of fuel and oil pressure for the engine to function properly.
If the battery is completely dead, it won't have enough power to turn over the engine, even with a jump start. In this case, you'll need to replace the battery to get your car running again. Another reason why a car battery won't jump is because there is a problem with the charging system.
Impact on alternators from jump starts: The alternator's design makes it fairly impervious to negative effects from jump starting. However, the alternator can sustain instant damage if the polarity of the clamp connections is mistakenly reversed.
Is 10 minutes driving enough to charge the battery?
It takes most vehicles about 30 minutes of driving at highway speeds to fully recharge the battery. Keep in mind that 30 minutes is an average. If your battery is severely discharged, it may take even longer to recharge it.
Does running a car for 5 minutes charge the battery?
When idling, the engine is still turning at a certain revolution per minute (rpm) – so the alternator is still converting that into usable energy and charging the battery. But revving the car a few thousand rpm faster does actually make the alternator charge the battery faster.
How often should I start my car to keep the battery charged?
Key Takeaways. Car batteries vary based on car type/age, but generally, experts recommend starting the engine at least once a week and driving 10km (around 6 miles) or 30 minutes. Keeping your battery charged is essential for optimal performance and longevity.
Is it bad to rev your car engine? If you occasionally rev up your engine, it is considered to be a healthy habit, as it allows better oil circulation. But, if you are a habitual “rever”, you might be doing more harm than good to your vehicle.
Is it bad to Rev your car in neutral while driving?
Is revving the engine in neutral then putting it into drive at high RPMs bad for the transmission? Yes that's very bad for the transmission, and the drive shaft and the differential. You should never do that.
You should therefore allow your engine to rev to the redline at least once every few hundred miles – but only when the oil is warm and you're on a quiet road. Diesel cars may also have problems with clogged diesel particulate filters (DPFs), which are designed to trap harmful exhaust emissions.
If you spin an alternator significantly faster than it was designed to spin either by revving the engine way above its stock rev limiter or by modifying the pulley ratio, you can definitely damage it either immediately or in the long run.
Charging output can be tested on a vehicle with a digital voltmeter. A good alternator should produce about 13.5 to 14.5 volts with the engine idling. If the voltage reading is low (12.5 volts or less), it indicates a charging problem but does not tell you what's causing it.
