First off, I do want to thank Paul, Frankie and John Z for responding to my question about ignition switch/ballast resistor/coil wiring. With your help, I am confident my wiring is correct.

I do have a new problem that has cropped up, however.

I think I have a bad ignition switch.

My ignition switch is wired as per the photos and drawing that you all supplied, but there is voltage going to the + side of the coil when the switch is on the "Locked" and "Off" positions.

When the ignition switch is turned to the "On" position, the starter motor engages sporadically.

In "Cranking" position, the engine cranks.

The ignition switch in my car is probably the original 50 year plug Delco Remy unit. I am suspecting that when I removed the lock cylinder from the switch, I may have caused some internal damage to the switch when the lock cylinder was turned counter -clockwise.

Again, I have installed a complete Lectric Limited wiring harness. I believe the starter motor is wired correctly with the black wire with the large lug going on the same post as the battery cable on the solenoid and the purple wire going to the "S" post on the solenoid (Howerver, I have noted that in the drawing Frankie provided there is a green wire running from the ballast resistor to the solenoid, which I don't see in my harrness--possible problem?)

Are the symptoms I am describing typical of an original 50 year Delco Remy switch unit that has gone bad? Should there be any other things to look at in diagnosing the problem.

Again, my thanks to you all for your help.

Charles Evans
Reno, Nevada

 

The contact plate inside does get wore out. This may be causing your speradic starter as well as your voltage when in the "off" and "lock" position...IF you have it wired correctly. You can normally find NOS switches on ebay for around $50 or less.

 

Its worth it just to replace it if its old (worn out maybe?)...I haven't seen any NOS units for anything close to $50 but if Vette Daddy (Brett) says they are out there then I'm a believer.

You need to disconnect your battery until you resolve this...constant voltage to the coil is bad news and can overheat and burn up the coil...which is why later cars had the ACC (Accessory) position on the switch.

 

Thank you Brett and Frankie.

I have disconnected my battery, as I always do, even when the car is operational.

With regards to Frankie's comment, I noted the green wire running from the ballast resistor to the solenoid in your wiring drawing, but haven't seen that in any other drawing, including the original wiring diagram provided by Lectric Limited. Currently, the only two wires running to the starter solenoid is the black wire from the BAT terminal on the ignition switch and the purple wire from the SOL terminal on the ignition switch running to the S terminal on the solenoid. The engine will crank with these wires connected.

Is it a desirable modification to run the green wire in your drawing from the ballast resistor to the solenoid.

If so, do I run the wire from the coil side of the resistor to the R terminal on the solenoid (it would seem to make sense if R stands for resistor)?

 

There's no "R" (or "C") terminal on a '57 solenoid; that didn't start until 1958, which is why the '57 bypass circuit ran from the ignition switch "IGN2" terminal direct to the coil (+) terminal (green wire).

 

My 57 Corvette doesn't have its original starter/solenoid, it's a rebuilt unit that does have the "R" terminal on the solenoid.

But from reading the wiring diagram and reading the posts here, I realize the 57 doesn't utilize the cranking circuit from the ballast resistor to the solenoid. I would guess my question would be is this a desirable modification.

However, I have read your response and realize also that is the function of the "IGN2" terminal on the ignition switch. So I will leave things alone. I have ordered a new ignition switch.

My thanks again, John Z.

Charles Evans,
Reno Nevada