My '69 will only start up if it's jumped. Otherwise it wont even crank over. I've changed the alternator and battery and still no luck.

Assuming the new alternator is good, what else could be causing this problem?

Sounds like something is wired wrong ? Use a multi-meter to check for voltage with car running (14.5-15.2) w/o the car running the battery should hold (12.5-13).If you have the car running ,you can disconect the positive cable and car should stay running. use caution! DO NOT LET THE POS. CABLE TOUCH GROUND it will short out electrical system

Originally posted by DOUG G:
use caution! DO NOT LET THE POS. CABLE TOUCH GROUND it will short out electrical system Very true, and a very good reason to disconnect the negative cable instead.

I just checked it out today. 12.5 volts at the battery, 12.5 volts at the back of teh alternator.

Also it's the stlye alternator used on the 70s and 80s cars... internal regulator.

I tried 2 different alternators and I still got nothing at the back of the alternator. Could this have something to do with the way that the car is wired up?

Only 12.5 volts at alternator running? Too low! Should be 14+ volts.

Also since your running an internal regulated alternator, did you mod the external regulator?
regulator mod. link (http://www.camaros.net/techref/ftecref14.html)

[ 04-04-2004, 06:29 AM: Message edited by: DOUG G ]