Emergency Shutoff Devices and Alarms
Emergency shutoff devices are either electrically or
mechanically operated. Familiarize yourself with the
types and locations of the shutoff de vices, the conditions
which cause each control to function, and the resetting
procedure required to start the engine.
Always determine the cause of the shutdown. Have the
necessary repairs made before restarting the engine.
Emergency shutoff controls are for emergency use only.
Do not use an emergency shutoff device for a normal
Electric Shutoff Controls
The operation of all electric shutoff controls is similar: A
critical operating condition actuates a switch in the
sensing unit. The switch closes the circuit to the shutoff
kage to stop the fuel to the cylinders; thus stop ping the
engine. The shutoff control may require resetting before
the engine can start.
High Water Temperature Shutoff
The shutoff switch is located in the water temperature
regulator housing. Excessive water temperature closes
the switch. No resetting procedure is required: As the
coolant cools, the switch opens.
The sensing element must be submerged in the coolant
to operate. A low coolant level cannot actuate the
Low Oil Pressure Shutoff Switch
This switch is usually mounted on the side of the engine
with oil lines connected to the switch. Low engine oil
pressures closes the switch.