Hello I am new to the forum. I recently bought a 1978 corvette. It was running when I bought it but due to the safety inspection in Hawaii I could drive it cause it didn't pass safety. So I had to change out the power steering pump due to a leak. After changing that out ad putting the alternator back on I go and try to start the car and nothing zero. No power no crank no turn over absolutely nothing happens no power to the lights antenna anything. So I changed out the starter thought that could be the problem that didn't work. Changed the ignition switch that didn't work. Check all the fuses and fusible links, to my knowledge non of them are broke from what I read if you can pull them or if they are soft on either side they are no good. I am really confused on what it is and I think that it is something simple that I am missing. Please any help would be amazing I am running out of ideas as to what it could be. It has a 350 motor with a 4 speed manual trans. Thank you

It sounds like you have a dead battery. Somewhere along the way you may have left the door ajar enough to turn the courtesy and dome lights on which drained your battery. So before doing anything else charge your battery and see if it'll crank. Yes, it no doubt is a simple problem but you got flustered and started throwing new parts into it when the old parts were actually good.

Make sure the car is in PARK

Yes it happened to me! lol

Ha, I have done stupid things like that too and as I age I seem to be making more and more of them. Sad, huh? I have left my ignition switch in the ON position a couple of times recently and found my battery stone dead the next morning so its likely he just made a simple mistake and caused his problem.

Not being in park won't cause the lights and antenna not to work. You need to start with your meter leads on the battery and then move methodically down the line to find where you're losing your power. You'll probably find it somewhere near the battery cables or the ground going to the frame. Don't just replace parts, measure and find what's bad

I was recently working on my '64 and all of a sudden I lost all electrical power, nothing at all. This is a total frame-off restoration with all new wiring and most other electrical components. I started searching through all the main wiring connections and found nothing wrong. Finally checked my battery and it barely had a pulse. I put a charge on it and everything is back to normal. I guess 7 or 8 years on a battery isn't too bad.

The battery is brand new and in order to not drain it completely dead I unhook the battery every time I am done working on the car as a just in case. The battery is reading with a meter at 12.30 I know that is a little low I think that it is suppose to be at 12.40 or higher but not higher then 14.0 if that is correct please let me know. Thank you

Welcome to the forum, I too have a 78 in Hawaii. Small world, thought I was the only Hawaii C3 on the forum.

As others' mentioned if you ruled out the battery, could be a ground issue. I had a similar problem, both the battery cable and ground was bad. Replaced it and fixed the problem.
Mike

OK I will take a look at the battery cable itself I have checked and cleaned the ground. The battery cables are the new style ones or at least to me they are new and they screw into the side of the battery instead of on the top like I'm use to seeing it was a good thing is it better or worse.

I don't like the side mounts either. Forgot to mention you can check continuity with a multimeter.
Mike

I assume the battery connections have already been checked.
I have seen where the side mount bolts tighten but the cable is nowhere close to the battery....the bolts are too long. Confirm that they are the correct length.
Are you checking the ground cable where it bolts to the frame just underneath below the battery box?
Also use your multi meter to check the voltage at the starter itself, it should be a solid 12v.
There should be a ground cable from the engine to the frame right close to the starter as well.
Check all those out and report back.

Have you tried pushing the clutch in when starting .

How do you propose that the clutch can cause no lights or power antenna?

Check your ground cable from the battery to the frame. It's copper clad aluminum and prone to corrosion from those stupid side terminal batteries G.M thought were so great.

You should have 12v at the big lug on the starter at all times. Thats where the main cable from battery to starter. Do you have a schematic of your model?

Best to start your own thread on this rather than post in this conversation from 9 years ago.

Battery ground cable!!!!!