Yesterday i responded to an ad in the paper an came home with a 1969 Plymouth Valient 4-door slant six auto in really good shape.I already own a 1978 Aspen coupe slant six auto so now i'm double slanted.
My dilema lies here. every time I start the Val I need to jump it or put a fresh battery in her. With either the jump or the fresh battery it fires right up and runs better than some cars I've daily driven. Turn off the key, and try to start it back up and it either fires right up or more often it does absolutly nothing. No lights no clicks no nothing.I did the old pull the battery cable while the cars running altenator test and the Alt seems ok,plus the guage does not go all screwy while she's running.Does anyone have any suggestions for me?Thanks in advance guys.

I'm having a little trouble understanding your problem. You're saying the car sucks even a known-good battery dry overnight or in a couple of hours? Or you're saying the battery that came with the car refuses to hold a charge?

If the former, there's something that is drawing too much current with the engine switched off. Find it and fix it. A good way to do this is to start pulling and replacing fuses with the ignition off and the dome light bulb removed. The one that sparks and crackles as you reinstall it is the one that controls the circuit that is drawing too much current.

If the latter, buy and install a new battery.

Oh, and your car's name is spelled with an "A". Valiant. Not "Valient".

I'd try a new starter relay. Sure sign of one going bad = sometimes it starts, sometimes nothing at all, not even a 'click'. It's a cheap thing to replace, too. And get it a new ballast resistor while you're at the store.

Had a failing starter act the same way.

its fixed, ended up replacing all the cables to the starter and battery, it really wasn't frying batteries, just when i changed them out the badly damaged cable(whichever it was) must have been conecting good enough tp start the car(ValiAnt)thanks