|
The sending units function as switches that close and complete the circuit to the engine block and become a ground when an undesirable condition is met like low oil pressure, high temperature, etc. There is 12 volts supplied from the keyed switch to one connector on the buzzer and another lead runs to the engine and then splits to the various sending units that are wired in parallel. If any of the sensors is failing in the closed position the buzzer will go off or if the wiring is chaffed and coming into contact with a grounded wire at any point, the buzzer will sound. I believe the perkins were wired to a temperature sending unit and oil pressure sensor originally but due to the age of these boats other items may have been added or removed from the circuitry. Disconnecting one at a time will find the fault or in the worst case, tracing the wire will find your short. For twin engine applications or boats with really quiet exhausts the buzzers are very useful in letting you know when an engine has stalled out before you go charging up to a dock with misplaced bravado.
|
Linear Mode
