The cranking output obtained from the motor is affected by the condition and charge of the battery, the circuit's wiring, and the engine's cranking requirement.

  • The battery should be checked and charged as needed before testing the starting system.
  • Check the wiring for clean, tight connections. The starter motor may draw several hundred amperes during cranking. Loose or dirty connections will cause excessive voltage drop.
  • Cables should also be checked for correct gauge size. These cables should also be inspected to see if they are too long. Excessive length causes excessive resistance.
  • Make certain the engine is filled with proper weight oil as recommended by the vehicle manufacturer.
  • Heavier-than-specified oil when coupled with low operating temperatures can drastically lower cranking speed to the point where the engine does not start and excessively high current is drawn by the starter.
  • Check the ignition switch for loose mounting, damaged wiring, sticking contacts, and loose connections.
  • Check the wiring and mounting of the safety switch, if so equipped, and make certain the switch is properly adjusted.
  • Check the mounting, wiring, and connections of the magnetic switch and starter motor. Also, be sure the starter pinion is properly adjusted.