So even in a later model truck the ignition switch when engaged could crank the engine over but not provide a circuit to the coil to generate spark? No. On later model trucks an ignition switch with a spring loaded "start" position was used in combination with a solenoid on the GM starter motor. The "start" position caused the solenoid to "pull in", pushing the starter drive ("Bendix") into the teeth on the flywheel and at the same time switching on battery power to the starter motor. On typical 12volt electrical systems a set of contacts inside the solenoid was also activated, providing full battery voltage to the ignition coil + terminal. This caused a hotter spark while cranking the engine to start. When the key was returned to the "run" position, the solenoid disengaged, the contacts providing battery voltage opened and lower coil voltage was supplied through a resistor while running.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
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