alternator help

nitros69bug · Post by **nitros69bug** » Tue Apr 17, 2007 7:54 am

every time i start my 69 bug the volts will be at 11.8 and i would rev the engine than the volts will go up to 12.8 and stay for a few min than go back to 11 volts than go back to 12.8 volts but when i bought this alternator it would charge at 14 volts how can i fix this

MNAirHead · Post by **MNAirHead** » Tue Apr 17, 2007 9:45 am

I mirrored this on the Electrical forum.. thanks for your post and welcome to STF.,

MNAirHead · Post by **MNAirHead** » Tue Apr 17, 2007 9:46 am

Internally or externally regulated alternator.. OR .. how many wires does it have coming directly off the top of it.

72bajaben · Post by **72bajaben** » Tue Apr 17, 2007 12:04 pm

im kinda confused as to what your saying.

i understand it as, it use to charge and 12.8 volts and you upgraded to an alt and now it is at 14 volts?

if this is the case then there is nothing to fix it should be at or around 13-14 volts. i have seen mine go upto 15 before.

but maybe im not seeing the question right.

nitros69bug · Post by **nitros69bug** » Wed Apr 18, 2007 8:04 am

my alternator doesint charge at 14 volts like when i bought it some thing has went wrong with it. and thair is a internal regulator it has a screw for the ground and one for the hot and one for the light that goes to the speedo this is a 55amp bosh

nitros69bug · Post by **nitros69bug** » Fri Apr 20, 2007 1:14 pm

ok now i changed my alternator with a brand new one it will charge at 12.3 volts than i rev my engine to 4,000 and it charges at 13.9 what is the problm i am sure that its not the alternator thanks to all

Speedy Jim · Post by **Speedy Jim** » Fri Apr 20, 2007 3:13 pm

How are you measuring the voltage? Where?

Do you have a multimeter that you could connect directly across the
battery posts? Or, right at the alternator B+ post?

nitros69bug · Post by **nitros69bug** » Fri Apr 20, 2007 7:14 pm

Ok my pioneer deck has a volt meter. so i replaced the alternator when i started the engine it was at 11.8 volts than i rev the engine to 4,500 rpm the volts went to 13.8 than after driving it a bit it stayd at 12.3 volts even when i rev the engine. So i put a big ground on it and a big charging wire and if i pull off my wire going to the speedo the light does not turn on. could that be the problm yah and when i take off the pos post after a cuple seconds the car will die. thanks to all CHAD

Speedy Jim · Post by **Speedy Jim** » Fri Apr 20, 2007 7:19 pm

if i pull off my wire going to the speedo the light does not turn on.

No, this is normal- not a problem.

I would not trust the meter in your deck.

Beg/borrow/steal a good multimeter and actually measure the
voltage at the battery posts.

nitros69bug · Post by **nitros69bug** » Fri Apr 20, 2007 8:04 pm

the charging wire looks about 6 or 8 gauge should i go biger

Speedy Jim · Post by **Speedy Jim** » Sat Apr 21, 2007 6:18 am

#6 ga should be plenty big...

nitros69bug · Post by **nitros69bug** » Thu Apr 26, 2007 12:38 pm

i got it to work right it was the hot that runs to the back of the speedo below the gen and turn signal so you do need that gen light to work