For the second engine starter, what is the maximum ON duration per cycle?

• A. 90 seconds
• B. 60 seconds
• C. 120 seconds
• D. 150 seconds

Answer: (A)

The key idea here is how long a starter can stay energized in one crank attempt without risking damage. Starters overheat if they’re fed power too long, so systems set a maximum ON duration per cycle to protect the motor and the electrical system. For the second engine starter, that limit is ninety seconds. This gives enough time to crank and attempt a start under typical conditions, while still preventing overheating or excessive wear.

If you crank only sixty seconds, you might not give the engine enough time to start in tougher conditions (cold weather, marginal battery voltage, or lean/flooded fuel conditions). Going longer than ninety seconds—like 120 or 150 seconds—greatly increases the risk of overheating the starter windings and draining the battery, which could lead to a failure to start or damage that takes time to cure. So ninety seconds is the best balance for the second starter.