[blu60]

Good day all

My SIII has recently begun acting funny when I start it. Here's the symptom and tell me what you think I should test.

When starting the engine - key in starting position starter spins nicely, the engine only gets enough spark when I put the key from "start" to "on", she fires right up smooth idle and plenty of power.

I have removed points and added Pertronix years ago, recent Lucas coil, replaced ignition switch which made no difference.

Voltage at the (+) coil when key is in the “on” position is 11.4, and 9.4 V when in the “start” position, and 12.4 at the battery terminals

thanks for any ideas

Herman
1973 88 NADA -

 

[frogeye61]

This is a typical problem of a defective ignition/starter switch. It is loosing contact to the ignition when starter contact is made. Being a long-time mechanic, I have in the past disassembled and repaired these switches - on just about every car except a Land Rover (mine has a push-button). If you try and it fails, it costs no more than just buying a replacement in the first place.

 

[roverandom]

Sounds like you need a new coil. Try a known good unit and compare voltage readings.
I'm assuming you have checked the wiring loom?