The Model T engine component first assembled on an assembly line was the magneto.
The Model T used a low-voltage magneto built into the engine’s flywheel. As the flywheel rotated, the magneto generated electrical current for the trembler coils, which then provided the spark needed to ignite the fuel-air mixture. This unusual arrangement helped keep the ignition system simple and durable.
Ford’s assembly-line methods developed gradually rather than appearing fully formed on one day. The magneto was the first Model T component placed into assembly-line production, and the approach was later copied across other production areas. The system helped Ford reduce manufacturing time and lower the car’s price.
A common mix-up is confusing the magneto with the starter or battery. Early Model Ts were hand-cranked, and the magneto supplied ignition current while the engine was running; electric starting equipment became available later and did not replace the magneto system.