Safety Shutdown Switches; Exhaust Temperature Switch; Low Oil Pressure Switch; Engine Circuit Breaker - Westerbeke 4.5 BCG Operator's Manual

SAFETY SHUTDOWN SWITCHES
. SAFETY SHUTDOWN SWITCHES
The engine is protected by a variety of shutdown switches.
Should a shutdown occur, do not attempt to restart without
finding and correcting tlie cause. Refer to the heading ·
Engine starts, nms
and
then shuts down in the ENGINE
TROUBLESHOOTING section of this manual.
.
The following is a description of these automatic shutdown
switches:
EXHAUST
TEMPERATURE
SWITCH
Exhaust Temperature Switch
An exhaust temperature switch is located on the exhaust
elbow. This switch will open and interrupt the DC voltage to
the ignition coil (which turns OFF the engine), should the
switch's sensor
indicate
an excessive exhaust temperature (an
inadequate supply· of raw water coolant causes high exhaust
temperatures). This switch opens at 260° - 270° F
( 127° - 132° C) and resets at approximately 225°F (107° C).
High Water Temperature SWitch
A high water temperature switch is located on the thermostat
housing. This switch will open and intenupt the DC voltage
to the ignition coil (which turns OFF the engine), should the
fresh water coolant's operating temperature reach
approximately 205° F (96° C).
This switch resets at 195° F
(1
OT C).
low Oil Pressure Switch
A low oil pressure shutdown switch is located off the
engine's oil gallery. The switch is·kept closed by engine oil
pressure. Should the engine's oil pressure
fall
to
10 - 15
psi,
the switch will open
interrupting
the DC
vo!cage to
the
ignition coil (which turns OFF the engine).
LOW Oil PRESSURE SWITCH
Oil
FILTER.
High RPM Shutdown SWitch
An overspeed shutdown switch shuts OFF the generator
set.
by grounding out the ignition system should the engine's
speed reach approximately 2175 rpm. Reset the switch by
momentarily depressing the STOP switch. (Make
sure
the
cause of the engine overspeed shutdown is corrected).
Engine Circuit Breaker
The. generator's engine is protected by an engine mounted
manual reset circuit breaker (20 amps DC). Excessive current
draw or electrical overload anywhere in the instrument panel
wiring or engine wiring will cause the breaker to trip. In this
event the generator will shut down because the opened
breaker interrupts the DC circuit to the K2-run relay. If this
should occur, check and repair the source of the problem.
After repairing the fault, reset the breaker and restart the
generator.
Overspeed PC Board
Inside the Control Box on the generator is a solid state
Overspeed PC Board. It monitors engine rpm via ignition
coil pulses. If these pulses reach a preset point. The PC
Board grounds the ignition and shuts the generator down.
Press the STOP switch to re-set the PC Board.
(For test purpose ONLY to determine a faulty PC Board
that will not re-set. Lift the Tl connection off the board
and attempt to start the generator).
. Engines"& Generators
11