Stingre'

I'm building a 1974 neglected lil turd. I got it running by installing HEI and fixing many vacuum leaks but there is a weird electrical issue. Half the time I turn the key I get nothing. Other times it will start ten times in a row (when I was setting timing) when it starts it literally runs like a Swiss watch, no misfire, 700 rpm in gear. Other times I turn the key and not even a click. The windows still work amp gauge drops but nothing. I'll wait half an hour then boom it fires right up....

Any ideas ? Guesses ? Let's make this fun, if I try your guess and it works I'll PayPal you $50. I'm stumped

Thanks for your future ideas, this is gunna be fun

SPCL FX

Starter?

OldCarBum

Does the starter spin the motor or is everything dead?
Fuel, Spark when It doesn't fire?
Did you check all your grounds?

SPCL FX

Btw, when I got mine I was told the engine was locked up ! I put a battery in it , turned the key and click ! Removed the starter and put in a new one and she runs just like yours ! Sometimes when a starter has been well used they will develop a " bad spot" from the heat off the engine and the starter being in one place which can cause them to work sometimes and sometimes not! Just my guess though!

Stingre'

Starter looks new, haven't replaced it yet but I did remove the solenoid and put an aftermarket heat shield on it. The wires going to the starter are original and barely there.

Stingre'

I don't even get a click.

Stingre'

Grounds are secure

Stingre'

I'm pulling the motor soon, upgrading to a vortec 350 Dart heads Fitech fuel injection ZZ9 Roller cam... I've been building this motor for awhile and decided to put it in the Vette because the original motor didn't run, now it does albeit sporadically due to the electrical issue. But if I can figure out what the issue is I'll delay the vortec motor install for awhile.

JayRay

Sounds like a bad fuseable link. There is one on your starter, one on your alternator and another one I believe, I forget where. Mine has done this once and then everything came back on 30 minutes later and has not happened again, yet.

Easy Mike

My 74 would occasionally do that. I would reset the seat belt interlock and be on my way.

Rescue Rogers

is it an automatic? It sooounds like a nuetral safety switch, key linkage to the ignition switch or clutch saftey switch, something that is just on the edge of being "in" tolerence. My subaru is doing the same thing, I just jam the gear shifter further into park and it fires up. Intermittent problems like yours that arent tied to heat are usually somethiing that just isnt in the sweet spot of its adjustment.

Next time it dosent start try it in nuetral, or push the clutch in further. with the key on move the steering column up an down slightly or try the key multiple times. I'm sure its something like that

Big2Bird

Sounds like the starter to me. Next time it does that, bridge the 2 large starter terminals with a large screw driver.

Rescue Rogers

If that starts it, it just means it's not the starter. You would still get a click from the solenoid if the starter was bad. Everything from the solenoid back is still suspect

mkdesign

I recently had the same issue with my Ragged '75. Everything would be fine and then when you least expect it, it would do the same thing. If I tried to start it with the parking lights on or even my satellite radio power jack still in the cigarette lighter. It would be a no go. And sometimes with nothing left on... well... nothing. Wait a bit and bite your lip the right way and it would start.
This was happening with a fresh battery and 12V to the accessories. My clamps to the battery were clean (old but clean) and tight. Or so I thought. The ground clamp at the battery had developed a crack in it. While it appeared okay and was sufficient to operate my accessories it was definitely not sufficient to provide a path to ground for the starter load.
I replaced both the battery clamps and not a problem since. Never discount a bad ground. You could test this by running a wire (the negative wire from your booster cables from the negative post on your battery to a good clean frame location.
Nothing spoils the fun of a Vette like not being able to turn it off until you are back in your own driveway.

Peterbuilt

Start with a fully charged battery and tight connections.

Follow the negative under the car and clean that connection.

At the starter clean the positive connection.

Confirm that you have a negative from the starter to the frame.

74's came with a 'seat belt interlock relay' (yours has been removed [was on the right side of the firewall]).
Check that the splice between the green/black to purple is good.

At the starter jumper from the battery positive to the small (closest to the block) 'S' terminal a few times to confirm that the starter works.

The neutral safety switch (under the console) may be out of adjustment, move the shifter between P and N.

Your HEI distributor needs 12 volts. The original is a resistor wire so the quick fix for that is to run a new wire from the IGN terminal in the fuse box to the HEI distributor.

Stingre'

Think this might be it Let me look into this

Makes the most sense right now.

Stingre'

Bypassed by previous owner, horribly I might add

Stingre'

Another contender

Stingre'

You guys are awesome I'm going to the Long Beach swapmeet tomorrow, 6am till ??? When I get home I'll try everything you guys suggested. I'll keep you guys informed

Stingre'

DEAD DEAD, Nothing
Checking grounds tomorrow