vanster

How far can I drive with a full battery charge on an alternator that is only putting out 11.2? I'm in LA and I need to get back to the Bay Area
Here is the twist. My wife is going to follow my in the 80 grey car
Thinking of buying a 2nd battery and swapping out as we go
Distance is about 360 miles. I just want to get it home to my own garage with my own tools

Adk46

Won't it go forever as long as you don't shut it off? But if you do, you can jump it to start?

ltoolio

No..won't run on forever without alternator functioning.

Tom. M

I only got about 1.5 hours on mine when my alternator went out just south of Portland (on the way home from Sharktoberfest). I put a new battery in and got the rest of the way (about 1 hour) and battery was still good (sitting at just over 10 volts).

I'd think 360 mile is a stretch...Do you have AAA(with 100 mile towing)? If not, probably worthwile (or even getting the 200 mile limit). You do afterall have a 928...could come in handy LOL.

Good luck...

rnixon

You're in the right place to get it fixed.

Jerry Feather

Van, I suspect that the trouble you are going to present yourself with somewhere out on the road in the Valley is much greater than the trouble and time it is going to take you to buy a few tools in LA, if you really need to, and a rebuilt alternator, or good used one (928 Int'l?) and change it out before you set out. Some guys up in Canada changed out an alternator in a parking lot at one of the 928 functions there a couple of years ago. It shouldn't be that big a job for you.

vanster

The big issue is that I need to be home by 3pm on Wednesday
And I'm pressed for time here, no time to go to Marks to get an alternator. If I could get a one at one of the local parts store, I would buy the tools. Planning on going up 101 not 5
Thinking maybe I can get Tom to Fed Ex overnight and I could install it tomorrow night
Hummmmm

jcorenman

Val,

If the alternator is really putting out 11 volts (i.e. actually delivering current but at a low voltage) then it won't charge the battery but can run the car forever-- the ECU's, ignition and fuel pump will run OK at 11 volts.

That said, if you are reading 11 volts then the alternator is probably putting out zero, and what you are reading is the remaining battery voltage. A fully-charged battery in like-new condition would be good for 3-4 hours, max, real life is probably 1-2 hours. Which of course means you will get farther by driving faster

928 Int'l has rebuilt alternators for $249, and you will need a few wrenches. There are worse roadside jobs.

Edit: Check the local auto parts stores, Bosch rebuilds should be available from a local warehouse.

James Bailey

If you have two 928s driving you could switch batteries every couple hours .....

Donald Smith

Ideally, swap the batteries every hour, otherwise, bring battery cables if you try for 2 hours. Or,buy a spare battery, and sell it when you're home.
GL

FredR

I like lateral thinkers! I think we can safely assume he will drive home during daylight hours!

If Van does go down this route it would be prudent to ensure he has a pair of jumps leads [in case the freshly drained battery cannot start the car with the good alternator].

Not so sure on this one but would it be prudent to isolate the duff alternator just in case the failure has created a path to earth [a failed diode?] that would thus flatten the battery prematurely.

Rgds

Fred

Speedtoys

Man....replace it today, you'll be done by noon if you had it and started now.

And..its easy enough I _would_ trust even a pep boys shop to do it.

Extremely easy to do if you dont wanna do it yourself.


You are greatly complicating things, and asking for secondary issues in this swap and hope for the best environment.

Jim Devine

Not sure you can switch batteries between the cars. Aren't the 80 & 86.5 batteries & battery boxes different sizes, 86.5 being smaller?

James Bailey

the box is smaller but often the early cars get the smaller batteries...when I lost an alternator at the track on a Saturday I bought a good charger and used it that night (found a plug next to a coke machine)....did all my runs the next day. Charged it for about an hour. Drove 1/2 way home stopped for another hour charge then drove home Kind of like driving a Tesla without all those Tax credits......

vanster

I just called Tom and he has a workable alt. Sending it via Fed Ex for tomorrow am
Found a guy with a lift just a few blocks away. Should be smooth sailing home
Thanks to all for the advice and help