1966 pontiac catalina won't hold a charge
 

my friend is selling me his '66 pontiac catalina w/the 421. but it won't hold a charge. he is not mechanically familiar with cars. so i have pretty much narrowed it down to the alternator but was posting this to see if anyone else had any ideas also. he charges the battery overnight and puts it in the car in the morning. it fires right up everytime and runs as smooth as silk. but if it sits overnight or for longer than 4 hrs the battery is completly dead. so if anyone has any thoughts on this then please feel free to comment. and leave the negative comments off of my post. thanks.

Re: 1966 pontiac catalina won't hold a charge
 

It's the Alternator.
/thread

Re: 1966 pontiac catalina won't hold a charge
 

ok. thanks i will check that out. thats what i figured it was.

Re: 1966 pontiac catalina won't hold a charge
 

Sounds like there is a parasitic drain somewhere. Disconnect the alternator and let the car sit and see what happens. If it still goes dead you'll need to use a multimeter to track down the source of the current draw.

Re: 1966 pontiac catalina won't hold a charge
 

Hook up a volt gauge or use a multimeter and start unplugging electrical connectors and fuses. When it drops there's your draw. It could also be the battery. Depending on how old it is.