Hi all, i'm new here, I have a 1969 Pontiac Lemans with a Rebuilt 400 not starting. It started when I was doing the tune up on it, I changed the oil and spark plugs, but the dumb thing I did was I disconnected all the spark plug wires at once (I know, dumb). So I think I mixed the wires and after a few tries to turn on the car, it will now not even start, making no noise. This was about two days ago, today, I turned the engine and rewired the spark plugs wires and into the correct firing order, but still no noise or starting. The one thing that I do notice is when trying to start the car, smoke starts to come out of the battery cable. What should I do? What could it be, did I burn out the Ignition coil, starter? Please Help!!!  

I suspect your battery needs to be charged or replaced. It should be able to turn over your engine regardless as to whether the plug wires are installed correctly or not.

Since it won't "click" but is drawing enough current to smoke the battery cable, I'm guessing your 400 is like mine, in that the starter gear won't disengage from the flywheel teeth until the engine fires and kicks it out of mesh. If that's the case, and your battery is too weak to turn over the engine, that would explain why the starter doesn't "click", the engine isn't turning, yet it's smoking the battery cable.

Since your plug wires were (or still are) installed incorrectly and the engine isn't firing, the starter gear is still meshed with the flywheel.

I would first charge the battery. While it's charging I'd re-check the plug wires and make certain you get the firing order correct. If the battery is accepting a charge and has enough time to get fully recharged, your engine should crank right over, even if the plug wires are incorrect. If it still fails to crank, then I'd pull the battery and have it load tested at your auto parts store.

Once you get the battery squared away and have the plug wires back where they should be, you should be fine. If it still fails to crank, then you'll need to look at the starter, as it or the solenoid on it may have gone bad. (You didn't mention if you've had starting problems in the past)

Check out that battery and let me know if you're back in business!
Kevin