Inertia Fuel Shutoff Switch: Description and Operation
Typical Inertia Fuel Shut-Off Switch:
PURPOSE
The inertia switch is used to shut the fuel pump "OFF" in the event of a collision.
OPERATION
When a sharp impact occurs, the ball breaks loose from the magnet, rolls up a conical ramp and strikes a target plate. This opens the electrical contacts of the switch and disrupts power to the electric fuel pump. The engine will quit running within a few seconds after the fuel pump loses power. The inertia switch must then be manually reset before the engine can be restarted.
NOTE: In the reset position, the button can be pressed an additional 1.59 mm (0.0625 in) against a spring. This is a normal condition.
WARNING: DO NOT reset the inertia switch button if you see or smell fuel.
Typical Inertia Fuel Shut-Off Switch:
CONSTRUCTION
The inertia switch consists of a steel ball held in place by a magnet.