What Should An Alternator Charge At Idle?

Can you spin an alternator too fast?

So on any given car with an idle speed of 800 rpms, the alternator is now spinning at 2,400 rpms, 1,700 rpms past when it actually turns on.

This, according to my testing, is too high.

At 6,500 rpms you are now spinning the alternator at 19,500 rpms, seriously over spun..

How long does an alternator last?

about seven yearsThe battery’s job is to start the car, and the alternator keeps it running.” Gunning says an alternator typically lasts about seven years — or about 100,000 to 150,000 miles, says Waits. Some mechanics, though, say they typically see alternators last about 80,000 miles.

What should my alternator be charging at?

A car alternator needs to be putting out at least 13-14 volts (ideally between 13.8 and 14.2 volts) to effectively charge a 12 volt car battery.

At what RPM does an alternator start charging?

The minimum RPM is highly dependent on the specification of alternator. But a basic alternator will produce charging current anything above 2000 rpm. We can safely say, an economy car will idle around 750 rpm, a sports car around 1250 rpm and a race car around 2000 rpm.

Do alternators charge at idle?

Yes, the alternator does charge the battery while the car is idling – regardless of the load on the battery. However, if your electrical use load (radio, lights, fan, etc) exceeds the amount of charge the battery is receiving from the alternator, you will end up with a discharged battery at some point.

Does battery charge while idling?

Do Car Batteries Charge While the Engine Is Idling? The answer is ‘YES’, yes the car battery does charge while the engine is idling. … Then the alternator is producing AC current, thereby charging the battery while your car is idling.

How long should I leave my car running to charge the battery?

Remember: After you’ve done a jump start, you’ll need to keep the vehicle’s engine running for around 30 minutes to allow the alternator time to charge the battery sufficiently.

How long should you idle a car to charge the battery?

If you find any of these cars start easily (the starter spins quickly), battery status is likely quite good, and a short drive or idling for 10 to 15 minutes may be adequate to keep the battery full, if done once every two weeks. If slower cranking is noted, a half hour drive once a week should do the trick.

How much HP does an alternator draw?

How much engine horse power does the alternator take? An alternator typically takes about 1 HP (horse power) for every 25 amps of power generated. So, a 100 amp alternator will require about 4 HP at full output. Most alternators do not operate at full output for very long.

What happens if you put a bigger alternator in your car?

Will a higher amperage alternator cause any problems with my stock electrical system? A higher amperage alternator will not pose any problems to the vehicle’s electrical system. Amperage will flow to only those components that can use the energy and supply as much amperage as the component can consume.

What voltage should an alternator put out at idle?

Read the voltage on the meter – Start the engine and observe the voltage on the meter. The voltage should read a minimum of 13 volts. A good alternator should put out between **13.5-14.5 volts.

Does revving engine charge battery faster?

Revving your engine does charge your battery faster, but only when the battery is in a significant state of discharge. … Revving the engine will charge the battery faster because the alternator increases this amperage. When you rev the engine, the alternator begins to run faster, which helps charge the battery.

Can high rpm damage alternator?

TOO HIGH OF RPM WILL DAMAGE ANYTHING. INCLUDING ALTERNATORS. YOU IMPORTANTLY MUST BE AWARE THAT IF THE ALTERNATOR IS BELT DRIVEN, THE DIFFERENCE IN SIZE OF THE TWO BELT PULLEYS MIGHT HAVE THE ALTERNATOR TURNING FASTER THAN THE ENGINE RPM, MAYBE MANY TIMES FASTER. … FOR YOUR ALTERNATOR, WILL NOT BE AS EASY TO FIND.

How do I know if my alternator is draining my battery?

6 Symptoms of a Failing AlternatorThe indicator light. … Headlights are dim or flickering. … Other electrical failures. … Strange noises. … Car stalls or has difficulty starting. … Battery dies.

How many amps should my alternator be?

100 ampsMost factory alternators are rated at 65 to 100 amps and are capable of handling your vehicle’s basic necessities, such as headlights, gauges, fuel pumps, A/C, etc. These alternators also typically come with a 10 to 15 percent reserve to handle additional accessories.

Can a car run with a bad alternator?

The alternator in your car provides power to the spark plugs that ignite the gas in your engine. If your alternator is beginning to go bad there might not be enough power in your spark plugs to start your car or keep your car running.

What causes alternator to drop voltage?

Poor ground connections are an often-overlooked cause of low charging output and alternator failure. Voltage drops on the positive side of the charging circuit can cause undercharging. Voltage drops on the negative side can cause overcharging.

Do alternators work at idle?

The alternator works at idle but at a bare minimum. It needs more rpm than is provided at idle to provide enough current for charging the system. That is why in a jump starting situation the donor car must increase the idle to supply the recipient with the “jump”.

What are signs of bad alternator?

7 Signs of a Failing AlternatorDim or Overly Bright Lights. … Dead Battery. … Slow or Malfunctioning Accessories. … Trouble Starting or Frequent Stalling. … Growling or Whining Noises. … Smell of Burning Rubber or Wires. … Battery Warning Light on Dash.Aug 24, 2020

What voltage is too low for an alternator?

A reading of more than 0.2 volts means trouble. Ideally, the voltage drop across any connection should be zero or less than 0.1 volts. Poor ground connections are an often-overlooked cause of low charging output and alternator failure.

Is 15 volts too high for alternator?

So, to answer your question, Yes, 15 volts is too high. Most car alternators, that normally recharge your battery after every start, and provide power while the engine is running, are normally voltage regulated to about 13.8 to 14.0 volts. … Above this, and it will gas increasingly with increasing voltage.

Is 14.7 volts too high?

Charging voltages over 14.7 volts can prematurely dry the battery by boiling out electrolyte, and increase risk of a battery hydrogen gas explosion. … Less than 14.3 would be a “weak” alternator or regulator. Much less than 14.2 at a fast idle is bad wiring, bad alternator or regulator, or a bad connection or fuse link.

How long should I let my car idle to charge the battery?

Lastly, you may have heard that idling your car for 15-20 minutes is a good alternative method to recharge your battery. While idling older vehicles for 15-20 minutes may give them enough of a charge to restart, this approach is generally not recommended.

Which alternator has least speed?

An alternator coupled with hydraulic turbine has the least speed. Explanation: An alternator is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current.

Is 13 volts too low for alternator?

For some alternators, it’s normal to see as low as 13 volts. For some, a constant 13.6 volts is an indication of a problem. For others, it’s normal to see as high as 16 volts for long stretches. Still, it’s perfectly normal for others to see the alternator not charge at all intermittently.