Alternator, battery, or something else?

[70spider]

Well, I was suppose to be working on the suspension today but gave up on the top shock nuts and took the wife out for a drive, it was a great day for it, 70 degrees and sunny. Well I went to start the car after going to the store and it wouldn't . Called my son he came out and we jumped started him and went home. This is the third time I have gone some place and tried to start the car only to have to get a jump. I thought at first it was the ignition switch but I don't think it is now due to the fact if I jump the car it starts.
Well when I got home I started him turned it off and started him again, did this 4 times without a problem. Next while it was running I disconnected the negative battery cable and it ran fine, it did kinda drop a few rpms intermittently but nothing that would cause it to die. So is it the alternator not charging all the time or is a battery going bad?
Either way I guess the only solution is to buy an alternator and battery and hope it doesn't happen again, but I sure would like to know which the culprit is.

[RRoller123]

Check the white block connector (I think it is either C17 or C35) just aft of the ignition switch (maybe 6"), it gets biffed a lot by legs, etc. and can become loose and intermittent. This happened in mine and caused the exact same problem.

[focodave]

I don't want to sound like "that guy", but you don't want to remove the battery cable while the car is running.
You can do some real damage that way.
If you want to test your charging system, keep the battery connected while the car is running and measure the voltage at the battery terminals. You want to see anywhere from 13.2 to 14.5 volts DC, while the car is running. If you get anything less than that, you have a problem.

[DieselSpider]

Don't guess, most autoparts stores will test your battery and charging system for you without a fee and let you know where the problem lies and whether you need to repair the charging system or need a new battery or need both. It could also be something as simple as the cooling fan not turning off and draining the battery while you were shopping.

[spider2081]

Does the car not crank?? Does the starter solenoid click?? Is the car a 1970 Spider?? Did you rock the car in gear?? Have you tried push starting it when this happens??
More information about your problem would help a lot.

[70spider]

Does the car not crank?? Does the starter solenoid click?? Is the car a 1970 Spider?? Did you rock the car in gear?? Have you tried push starting it when this happens??
More information about your problem would help a lot.

The car does the click of death then if I try again nothing, not even a click. Yes it is a 1970. I did the rock the car in gear, I don't suspect the starter due to I just got a new gear reduction unit from AR, all wires are secured. I haven't tried to push start it yet because my wife doesn't feel comfortable popping the clutch in a parking lot.
In other posts when this happens the suspect is the ignition switch, but if it was the switch why would jumping the car start it?

Don't guess, most autoparts stores will test your battery and charging system for you without a fee and let you know where the problem lies and whether you need to repair the charging system or need a new battery or need both.

I thought about taking in the battery today if I find the time, nearest autopart store is 20mi. away.
I'll check all my wire connections again, especially the grounds, when I work on the suspension today.
Thanks everyone.

[spider2081]

Not sure but I think there is a nylon 3 or 4 pin connector on the driver side fender well that the power to the ignition switch and power out of the switch for the starter solenoid pass through. I think the wire colors are red (starter solenoid) black (power to ignition switch) Brown (power to ignition switch). Some people eliminate this connector and splice the wires together. I believe the connector was used in the cars assembly and serves no purpose now. This connector was eliminated in later models and replaced with single bullet type connectors.