no alternator

Anybody have an idea of how far I could drive in daylight with alternator that is not working and fully charged battery? No headlights either. Thanks

 

Reserve capacity is the number of minutes a battery can provide a 25 amp draw until it drops to 10.5 volts. In theory, that’s the number of minutes that you can drive with only the necessities running. There will be a huge difference between a brand new 27F and a 7 year old 24F.
Personally, I wouldn’t push it more than 1 hour on a fairly new fully charged battery. This is also assuming that the serpentine belt is still there and turning everything else.

 

To the end of your driveway.

 

With everything off that you don’t need on. I’ve seen trucks go 20-30 miles. All depends on the heath of the battery. But be warned unless it’s a deep cycle, you’ll likely end up killing the battery

 

There is a lot of things going on fuel pumps, signal/brake lights, engine controls, radio memory etc it's a crapshoot end of the drive probably isn't too far off the mark!

 

O.P. can go drive anywhere,and when his truck quits he can then pay an expensive tow bill PLUS buy a new alternator.

 

I got about 30km on mine till every dash light came on and Speedo went crazy. Good luck!

 

If its the same battery that was used during the alternators death it is likely in poor state of health.

Even with it at 12.6v its unlikely to last more than 10 minutes.

 

The best answer is Don't do it.

 

While there is Only one way to find out, I wouldn’t try it.

 

Not very far.... maybe 10 ft

 

You will make it to the end of the drive

 

It depends on the circumstances. If I was an hour away from home and the alternator died, I would make sure the serpentine belt was still there, jump on the freeway and haul ass for home. If I didn't make it, I would go to plan B. Have a friend bring out a fully charged battery or have a friend come out and hook up jumper cables for an hour and then follow me home. If the alternator died in my driveway, I wouldn't take it for a scenic drive out of town. I might take it to the store to get beer though.

 

We did this once with a 1990 suburban. Alternator started making noise, then it quit charging. It went about 2 hours home, then the bearings in the alternator completely gave up, sliced the serpentine belt in half the long way, and then caught fire.

That was the day I learned that there are alternator cores that the store won't take. If the fan on the front has dug into the housing and there are chunks of aluminum everywhere, thats a pretty good sign.

I wouldn't do it unless it was a very short trip. Vehicles these days are way more electrically hungry anyway.

 

Just far enough away to be inconvient or close to a parts store... give or take 1hr walk

 

Lol maybe you should tow. AAa membership is not that expensive

 

As a general rule of thumb if the charge light comes on, and you have a good battery expect 15 mins of run time, depending on what goes wrong in the alternator, it can act like a huge load as the voltage reg, full fields, but nothing leaves the alternator, alternator gets hot and acts like a toaster, sucking the battery down in mins, other times it can last hours as its not trying to energize the field.
so depending on how the alt fails is the deciding factor on how long it lasts. unplugging the field wires on the alternator helps extend run time

 

Possible electrical fire also.