Intermittent no crank, but always has solenoid click

[SRQTerry]

Working on a '72 Camaro with basic old school starter circuit wiring for a 350 sbc. Problem is intermittent no starter engagement, but solenoid always clicks. Usually repetitive cycles of the key cylinder (3-8 times) results in starter engagement and engine cranking. Starter is new, battery is new Optima freshly charged, Wiring has been double checked at starter attachments, battery attachments and ground at block. I have NOT changed the ignition switch on the lower steering column. I have no idea how old (worn) it is either. Could this symptom be caused by a worn out ign switch?
Thanks, Terry

 

[mallard]

Corrosion inside the battery cables? I've run into that before.

 

[Gary S]

Not likely the ignition switch. The switch is making the solenoid click, so it is most likely good.
Bad battery cables or connections can cause this type of problem. Try starting it with the lights on. If it clicks and the lights stay on, the cables are good. If it clicks and the lights go off, the cables are bad.
Also, inspect the starter carefully. I've seen bad solenoid to starter connections do exactly this. Also, bad brushes or commutater inside the starter can also cause it.

 

[onovakind67]

Probably bad contacts inside the solenoid, the ones that carry the current to the starter motor.

 

[SRQTerry]

Fixed !!

Just in case someone else has this symptom someday I'll post the solution. It was in fact the "slider" ignition switch that bolts to the top of the steering column. $17 part but you have to drop the steering column down to get at it. The internal contacts in this switch were badly worn (I took it apart) and so many times when in the crank position it would not carry enough current to fully engage the solenoid and turn the starter.

 

[McCune]

The switch signal is not carrying the amperage to the S terminal. You can add a relay, which is a bullet proof fix or find out where the drop in power is.

SRQTerry is right on the money as well.