Low Power Problems - 1970 Chevorlet Nova

[jamesmartinez]

Hey there.

I'm having fairly bad problems here - let me get right to the point.

1970 Chevrolet Nova

While the car is running, over 20mph, the voltage meter says 10-12V. When idling, it falls down to 8-9V. If I shut the car off, it is unable to start without a jump. Once I get it rev'd up, it pushes the volt meter up to 10-12V again, then drops back down when idling. Also, it can't be a problem with the volt meter because all of the lights also dim; headlights and interior lights.

Thanks everyone,
James

[Ted W]

Sounds like you lost a cell in your battery or you don't have path to the battery. In short, check your battery.

[jamesmartinez]

I did that, as well as replaced the battery. No dice.

James

[Steve E.]

It's possible your alternator has a bad diode in it or your regulator is going out,get them checked and go from there, before you do, check all connections for cleanliness!

[Twitch]

A 70 Nova is easy to pull the alternator on so do that and take it to a local auto parts store to test for free. Most do it. The dim lights often means poor connections due probably to age of the car/wiring.

[jamesmartinez]

Thanks for all of the helpful tips.

I'll be taking out the alternator this weekend to see what I can do, as well as checking all of the connections.

Still, more responses would be great!

Thanks again,
James

[Oldcar_Mechanic]

I don't think you need any more responses. Twitch has pretty much hit the nail on the head. You need to start someplace before diving into other things. Work systematically and always start with the easy stuff. You'll probably find the problem once you get the diagnosis from the parts store.

One thing I would recommend is that if you have to change the Alternator, change the Voltage Regulator also at the same time.

If your battery is only capable of 10 volts while running, your lights will be dim.

Keep us posted as to what you find.
Ron